Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 28, 2016	Oct. 24, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 28, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3
Trading Symbol	LOCO
Entity Registrant Name	El Pollo Loco Holdings, Inc.
Entity Central Index Key	0001606366
Current Fiscal Year End Date	--12-28
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		38,473,772

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 28, 2016	Dec. 30, 2015
Current assets:
Cash and cash equivalents	$ 6,529	$ 6,101
Restricted cash	125	125
Accounts and other receivables, net	8,495	6,186
Inventories	1,834	1,899
Prepaid expenses and other current assets	3,426	2,656
Deferred tax assets	10,032	21,656
Total current assets	30,441	38,623
Property and equipment owned, net	117,259	102,421
Property held under capital leases, net	70	89
Goodwill	248,674	248,674
Trademarks	61,888	61,888
Other intangible assets, net	509	638
Deferred tax assets	6,891	6,891
Other assets	1,481	1,804
Total assets	467,213	461,028
Current liabilities:
Current portion of obligations under capital leases	159	177
Accounts payable	9,388	11,046
Accrued salaries and vacation	9,231	6,693
Accrued insurance	5,161	5,021
Accrued income taxes payable	32	67
Accrued interest	200	245
Accrued advertising		204
Other accrued expenses and current liabilities	13,903	16,126
Total current liabilities	38,074	39,579
Revolver loan	107,000	123,000
Obligations under capital leases, net of current portion	347	461
Deferred taxes, net of current portion	8,740	8,740
Other intangible liabilities, net	1,068	1,248
Other noncurrent liabilities	48,039	43,367
Total liabilities	203,268	216,395
Commitments and contingencies
Stockholders' Equity
Preferred stock, $0.01 par value, 100,000,000 shares authorized; none issued or outstanding
Common stock, $0.01 par value—200,000,000 shares authorized; 38,473,772 and 38,284,435 shares issued and outstanding	385	383
Additional paid-in-capital	371,024	369,635
Accumulated deficit	(107,464)	(125,385)
Total stockholders' equity	263,945	244,633
Total liabilities and stockholder’s equity	$ 467,213	$ 461,028

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 28, 2016	Dec. 30, 2015
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	38,473,772	38,284,435
Common stock, shares outstanding	38,473,772	38,284,435

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015	Sep. 28, 2016	Sep. 30, 2015
Revenue
Company-operated restaurant revenue	$ 89,738	$ 82,986	$ 268,984	$ 251,295
Franchise revenue	6,078	5,884	18,660	17,456
Total revenue	95,816	88,870	287,644	268,751
Cost of operations
Food and paper cost	26,960	26,371	80,760	80,549
Labor and related expenses	24,455	20,822	73,323	63,493
Occupancy and other operating expenses	20,071	18,207	58,401	52,732
Gain on recovery of insurance proceeds, lost profit	(502)		(502)
Company restaurant expenses	70,984	65,400	211,982	196,774
General and administrative expenses	8,252	6,316	25,776	20,206
Franchise expenses	797	925	2,960	2,620
Depreciation and amortization	4,074	3,278	11,796	9,624
Loss on disposal of assets	58	261	524	427
Expenses related to fire loss			48
Loss (gain) on recovery of insurance proceeds	148		(741)
Asset impairment and closed-store reserves	2,490	163	2,624	24
Total expenses	86,803	76,343	254,969	229,675
(Loss) gain on disposition of restaurants	(5)		28
Income from operations	9,008	12,527	32,703	39,076
Interest expense-net of interest income	785	810	2,441	3,035
Expenses related to selling shareholders				50
Income tax receivable agreement expense	182	546	411	1,022
Income before provision for income taxes	8,041	11,171	29,851	34,969
Provision for income taxes	2,830	6,505	11,930	16,281
Net income	$ 5,211	$ 4,666	$ 17,921	$ 18,688
Net income per share
Basic	$ 0.14	$ 0.12	$ 0.47	$ 0.49
Diluted	$ 0.13	$ 0.12	$ 0.46	$ 0.48
Weighted-average shares used in computing net income per share
Basic	38,415,189	38,275,317	38,331,400	37,837,610
Diluted	39,083,577	39,107,241	39,020,127	39,044,388

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 17,921	$ 18,688
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation and amortization	11,796	9,624
Stock-based compensation expense	244	608
Fire insurance proceeds for expenses paid and lost profit	257
Income tax receivable agreement expense	411	1,022
Gain on sale of restaurant	(28)
Loss on disposal of assets	524	427
Gain on recovery of insurance proceeds for property, equipment and expenses	(741)
Gain on recovery of insurance proceeds for lost profits	(502)
Impairment of property and equipment	2,508	136
Closed-store reserve	116	(112)
Amortization of deferred financing costs	229	229
Amortization of favorable and unfavorable leases, net	(51)	(128)
Excess income tax benefit related to share-based compensation plans	(169)	(5,700)
Deferred income taxes, net	11,624	10,581
Changes in operating assets and liabilities:
Accounts and other receivables, net	(2,066)	(292)
Inventories	57	148
Prepaid expenses and other current assets	(770)	1,278
Income taxes payable	134	5,670
Other assets	94	102
Accounts payable	(6,269)	500
Accrued salaries and vacation	2,538	(113)
Accrued insurance	140	1,032
Other accrued expenses and liabilities	1,673	(279)
Net cash flows provided by operating activities	39,670	43,421
Cash flows from investing activities:
Proceeds from sale of restaurant	1,465
Fire insurance proceeds for property and equipment	743
Purchase of property and equipment	(26,465)	(16,512)
Net cash flows used in investing activities	(24,257)	(16,512)
Cash flows from financing activities:
Payments on revolver loan	(16,000)	(40,000)
Proceeds from issuance of common stock, net of expenses	978	4,254
Payment of obligations under capital leases	(132)	(155)
Excess income tax benefit related to share-based compensation plans	169	5,700
Net cash flows used in financing activities	(14,985)	(30,201)
Increase (Decrease) in cash and cash equivalents	428	(3,292)
Cash and cash equivalents, beginning of period	6,101	11,499
Cash and cash equivalents, end of period	6,529	8,207
Supplemental cash flow information
Cash paid during the period for interest	2,355	2,781
Cash paid during the period for income taxes	173	30
Unpaid purchases of property and equipment	$ 4,599	4,567
Cashless stock option exercise		$ (34)

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 28, 2016
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Overview El Pollo Loco Holdings, Inc. (“Holdings”) is a Delaware corporation headquartered in Costa Mesa, California. Holdings and its direct and indirect subsidiaries are collectively known as “we,” “us” or the “Company.” Our activities are conducted principally through our indirect wholly-owned subsidiary, El Pollo Loco, Inc. (“EPL”), which develops, franchises, licenses, and operates quick-service restaurants under the name El Pollo Loco® and operates under one operating segment. At September 28, 2016, we operated 193 and franchised 253 El Pollo Loco restaurants. Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments necessary for a fair presentation of its financial position and results of operations and cash flows for the periods presented. Interim results of operations are not necessarily indicative of the results that may be achieved for the full year. The consolidated financial statements and related notes do not include all information and footnotes required by GAAP for annual reports. This quarterly report should be read in conjunction with the consolidated financial statements included in the Company’s annual report on Form 10-K for the year ended December 30, 2015. The Company uses a 52- or 53-week fiscal year ending on the last Wednesday of the calendar year. In a 52-week fiscal year, each quarter includes 13 weeks of operations; in a 53-week fiscal year, the first, second and third quarters each include 13 weeks of operations and the fourth quarter includes 14 weeks of operations. Every six or seven years a 53-week fiscal year occurs. Fiscal 2015 and 2016 are both 52-week years, ending on December 30, 2015 and December 28, 2016, respectively. Revenues, expenses, and other financial and operational figures may be elevated in a 53-week year. Holdings has no material assets or operations. Holdings and Holdings’ direct subsidiary, EPL Intermediate, Inc. (“Intermediate”), guarantee EPL’s 2014 Revolver (see Note 4) on a full and unconditional basis and Intermediate has no subsidiaries other than EPL. EPL is a separate and distinct legal entity, and has no obligation to make funds available to Intermediate. EPL and Intermediate may pay dividends to Intermediate and to Holdings, respectively. Under the 2014 Revolver, Holdings may not make certain payments such as cash dividends, except that it may, inter alia, (i) pay up to $1 million per year to repurchase or redeem qualified equity interests of Holdings held by past or present officers, directors, or employees (or their estates) of the Company upon death, disability, or termination of employment, (ii) pay under its income tax receivable agreement (the “TRA”), and, (iii) so long as no default or event of default has occurred and is continuing, (a) make non-cash repurchases of equity interests in connection with the exercise of stock options by directors and officers, provided that those equity interests represent a portion of the consideration of the exercise price of those stock options, (b) pay up to $2.5 million per year pursuant to stock option plans, employment agreements, or incentive plans, (c) make up to $5 million in other restricted payments per year, and (d) make other restricted payments, provided that such payments would not cause, in each case, on a pro forma basis, (x) its lease-adjusted consolidated leverage ratio to equal or exceed 4.25 times and (y) its consolidated fixed charge coverage ratio to be less than 1.75 times. Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of Holdings and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and revenue and expenses during the period reported. Actual results could materially differ from those estimates. The Company’s significant estimates include estimates for impairment of goodwill, intangible assets and property and equipment, insurance reserves, lease termination liabilities, closed store reserves, stock-based compensation, income tax receivable agreement liability, and income tax valuation allowances. Cash and Cash Equivalents The Company considers all highly-liquid instruments with a maturity of three months or less at the date of purchase to be cash equivalents. Restricted Cash The Company’s restricted cash represents cash collateral to one commercial bank for Company credit cards. Liquidity The Company’s principal liquidity requirements are to service our debt and to meet capital expenditure needs. At September 28, 2016, the Company’s total debt (including capital lease liabilities) was $107.5 million. The Company’s ability to make payments on its indebtedness and to fund planned capital expenditures depends on available cash and on its ability to generate adequate cash flows in the future, which, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory, and other factors that are beyond the Company’s control. Based on current operations, the Company believes that its cash flow from operations, available cash of $6.5 million at September 28, 2016, and available borrowings under the 2014 Revolver (which availability was approximately $85.8 million at September 28, 2016) will be adequate to meet the Company’s liquidity needs for the next 12 months. Gain on Recovery of Insurance Proceeds In November 2015, one of the Company’s restaurants incurred damage resulting from a fire. During the thirty-nine weeks ended September 28, 2016, we incurred costs directly related to the fire of $48,000, disposed of an additional $87,000 of assets and recognized gains of $741,000, related to the reimbursement of property and equipment and expenses incurred and $502,000 related to the reimbursement of lost profits. The reimbursement of lost profits is included in the accompanying consolidated statement of operations, for the thirteen and thirty-nine weeks ended September 28, 2016, as a reduction of Company restaurant expenses. The Company received from the insurance company cash of $1,000,000 during the thirty-nine weeks ended September 28, 2016 and $354,000, net of a $10,000 insurance deductible, on October 5, 2016. The $354,000 is included in accounts and other receivables in the condensed consolidated balance sheet as of September 28, 2016. In 2015, the Company disposed of $111,000 of assets related to the fire. The restaurant was reopened for business on March 14, 2016. Recent Accounting Pronouncements In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 addresses how certain cash receipts and cash payments are presented and classified in the statement of cash flows under Topic 230, Statement of Cash Flow, and other Topics. ASU 2016-15 is effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606) – Narrow-Scope Improvements and Practical Expedients. This ASU is intended to clarify two aspects of Topic 606: first, assessing the collectability criterion, options for the presentation of sales and similar taxes, noncash consideration, transition contract modifications, transition contract completion and secondly, technical corrections. The amendments in this update are effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods, and early application is permitted, but no earlier than fiscal years beginning after December 16, 2016. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606) – Identifying Performance Obligations and Licensing. This ASU is intended to clarify two aspects of Topic 606: identifying performance obligations and licensing implementation guidance. The amendments in this update are effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods, and early application is permitted, but no earlier than fiscal years beginning after December 16, 2016. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation – Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which is intended to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for annual periods beginning after December 15, 2016, and interim periods therein. Early application is permitted. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, “Leases.” The new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, "Financial Instruments – Overall: Recognition and Measurement of Financial Assets and Financial Liabilities." The pronouncement requires equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income, requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes, requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset, and eliminates the requirement for public business entities to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost. These changes become effective for the Company's fiscal year beginning December 28, 2017 and interim periods within that fiscal year. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In November 2015, the FASB issued ASU No. 2015-17, “Income Taxes” which requires that deferred tax liabilities and assets be classified as noncurrent in a classified balance sheet. Prior to the issuance of the standard, deferred tax liabilities and assets were required to be separately classified into a current amount and a noncurrent amount in the balance sheet. The new accounting guidance represents a change in accounting principle and the standard is required to be adopted in annual periods beginning after December 15, 2016. After the adoption of this ASU all deferred tax assets and liabilities will be classified as noncurrent on the consolidated balance sheet. In July 2015, the FASB issued ASU No. 2015-11, “Inventory (Topic 330).” The pronouncement was issued to simplify the measurement of inventory and changes the measurement from lower of cost or market to lower of cost and net realizable value. This pronouncement is effective for reporting periods beginning after December 15, 2016. The adoption of ASU 2015-11 is not expected to have a significant impact on the Company’s consolidated financial position or results of operations. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (ASU 2014-09)”, which supersedes nearly all existing revenue recognition guidance under GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing GAAP. The revised revenue standard is effective for public entities for annual periods beginning after December 15, 2017, and interim periods therein, using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). The Company is currently assessing the impact of this ASU on our consolidated financial statements. In August 2014, the FASB issued ASU No. 2014-15, Going Concern (“ASU 2014-15”). ASU 2014-15 provides GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. The standard will be effective for annual periods ending after December 15, 2016, and interim periods within annual periods beginning after December 15, 2016. Early application is permitted for annual or interim reporting periods for which the financial statements have not previously been issued. Upon adoption the Company will use the guidance in ASU 2014-15 to assess going concern. Subsequent Events Subsequent to September 28, 2016, the Company opened 4 new restaurants and made a $3.0 million pre-payment on the 2014 Revolver. On October 3, 2016, the Company announced a two unit franchise development agreement with Listo Way Group LLC to develop El Pollo Loco restaurants in Lafayette, Louisiana. On October 5, 2016, the Company received $354,000 in insurance proceeds related to damage resulting from a fire at one of the Company’s restaurants. On November 1, 2016, the Company amended the letters of credit related to the 2014 Revolver, thereby increasing the outstanding amount to $8.0 million. The Company evaluated subsequent events that have occurred after September 28, 2016, and determined that there were no other events or transactions occurring during this reporting period that require recognition or disclosure in the condensed consolidated financial statements. Concentration of Risk Cash and cash equivalents are maintained at financial institutions and, at times, balances may exceed federally-insured limits. The Company has never experienced any losses related to these balances. The Company had no suppliers for which amounts due at September 28, 2016 totaled greater than 10% of the Company’s accounts payable. As of December 30, 2015, the Company had two different suppliers for which amounts totaled 12% and 11% of the Company’s accounts payable. Purchases from the Company’s largest supplier totaled 33% for the thirteen weeks ended September 28, 2016, and 37% for the thirteen weeks ended September 30, 2015, of the Company’s purchases. Purchases from the Company’s largest supplier totaled 33% for the thirty-nine weeks ended September 28, 2016, and 37% for the thirty-nine weeks ended September 30, 2015, of the Company’s purchases. Company-operated and franchised restaurants in the greater Los Angeles area generated, in the aggregate, approximately 75% and 79% of total revenue for both the thirteen and thirty-nine weeks ended September 28, 2016 and September 30, 2015, respectively. Goodwill and Indefinite Lived Intangible Assets The Company’s indefinite lived intangible assets consist of trademarks. Goodwill represents the excess of cost over fair value of net identified assets acquired in business combinations accounted for under the purchase method. The Company does not amortize its goodwill and indefinite lived intangible assets. Goodwill resulted from historical acquisitions. Upon the sale of a restaurant, the Company evaluates whether there is a decrement of goodwill. The amount of goodwill included in the cost basis of the asset sold is determined based on the relative fair value of the portion of the reporting unit disposed of compared to the fair value of the reporting unit retained. The Company performs annual impairment tests for goodwill during the fourth fiscal quarter of each year, or more frequently if impairment indicators arise. The Company reviews goodwill for impairment utilizing either a qualitative assessment or a two-step process. If the Company decides that it is appropriate to perform a qualitative assessment and concludes that the fair value of a reporting unit more likely than not exceeds its carrying value, no further evaluation is necessary. If the Company performs the two-step process, the first step of the goodwill impairment test is used to identify potential impairment by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is considered not impaired and the second step of the impairment test is unnecessary. If the carrying amount of a reporting unit exceeds its fair value, the second step is performed to measure the amount of impairment by comparing the carrying amount of the goodwill to a determination of the implied value of the goodwill. If the carrying amount of goodwill is greater than the implied value, an impairment charge is recognized for the difference. The Company performs annual impairment tests for indefinite lived intangible assets during the fourth fiscal quarter of each year, or more frequently if impairment indicators arise. An impairment test consists of either a qualitative assessment or a comparison of the fair value of an intangible asset with its carrying amount. The excess of the carrying amount of an intangible asset over its fair value is its impairment loss. The assumptions used in the estimate of fair value are generally consistent with the past performance of the Company’s reporting segment and are also consistent with the projections and assumptions that are used in current operating plans. These assumptions are subject to change as a result of changing economic and competitive conditions. The Company did not identify any indicators of potential impairment during the thirteen and thirty-nine weeks ended September 28, 2016, and therefore did not perform any impairment review, nor did the Company record any impairment. Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment on a restaurant-by-restaurant basis whenever events or changes in circumstances indicate that the carrying value of certain assets may not be recoverable. If the Company concludes that the carrying value of certain assets will not be recovered based on expected undiscounted future cash flows, an impairment write-down is recorded to reduce the assets to their estimated fair value. The fair value is measured on a nonrecurring basis using unobservable (Level 3) inputs. Based on the results of the analysis, the Company recorded a non-cash impairment charge of $2.4 million for the thirteen and thirty-nine weeks ended September 28, 2016, related to non-recoverable assets of two restaurants in Arizona and Texas. The Company continues to monitor the recoverability of the carrying value of the assets of several other restaurants, including new restaurants opened in 2015 in Texas. Income Taxes The provision for income taxes, income taxes payable and deferred income taxes is determined using the asset and liability method. Deferred tax assets and liabilities are determined based on temporary differences between the financial carrying amounts and the tax bases of assets and liabilities using enacted tax rates in effect in the years in which the temporary differences are expected to reverse. On a periodic basis, the Company assesses the probability that its net deferred tax assets, if any, will be recovered. If, after evaluating all of the positive and negative evidence, a conclusion is made that it is more likely than not that some portion or all of the net deferred tax assets will not be recovered, a valuation allowance is provided by charging to tax expense to reserve the portion of deferred tax assets which are not expect to be realized. The Company reviews its filing positions for all open tax years in all U.S. federal and state jurisdictions where the Company is required to file. When there are uncertainties related to potential income tax benefits, in order to qualify for recognition, the position the Company takes has to have at least a “more likely than not” chance of being sustained (based on the position’s technical merits) upon challenge by the respective authorities. The term “more likely than not” means a likelihood of more than 50 percent. Otherwise, the Company may not recognize any of the potential tax benefit associated with the position. The Company recognizes a benefit for a tax position that meets the “more likely than not” criterion at the largest amount of tax benefit that is greater than 50 percent likely of being realized upon its effective resolution. Unrecognized tax benefits involve management’s judgment regarding the likelihood of the benefit being sustained. The final resolution of uncertain tax positions could result in adjustments to recorded amounts and may affect our results of operations, financial position, and cash flows. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company had no accrual for interest or penalties at September 28, 2016 or at December 30, 2015, and did not recognize interest or penalties during the thirteen or thirty-nine weeks ended September 28, 2016 or September 30, 2015, since there were no material unrecognized tax benefits. Management believes no material changes to the amount of unrecognized tax benefits will occur within the next twelve months. On July 30, 2014, the Company entered into the TRA. The TRA calls for the Company to pay to its pre-IPO stockholders 85% of the savings in cash that the Company realizes in its taxes as a result of utilizing its net operating losses and other tax attributes attributable to preceding periods.

Property and Equipment

9 Months Ended

Sep. 28, 2016

Property Plant And Equipment [Abstract]

Property and Equipment

2. PROPERTY AND EQUIPMENT

The costs and related accumulated depreciation and amortization of major classes of property are as follows (in thousands):

	September 28, 2016			December 30, 2015
Land	$	12,323		$	12,323
Buildings and improvements		121,875			111,349
Other property and equipment		64,065			58,525
Construction in progress		12,803			4,717
		211,066			186,914
Less: accumulated depreciation and amortization		(93,807	)		(84,493	)
	$	117,259		$	102,421

Depreciation expense was $4.1 million and $3.3 million for the thirteen weeks ended September 28, 2016 and September 30, 2015, respectively, and $11.8 million and $9.6 million for the thirty-nine weeks ended September 28, 2016 and September 30, 2015, respectively. The gross value of assets under capital leases for buildings and improvements was $1.6 million at September 28, 2016 and December 30, 2015. Accumulated depreciation for assets under capital leases was $1.5 million as of September 28, 2016 and December 30, 2015. For the thirteen weeks ended September 28, 2016, capital expenditures totaled $12.1 million, including $0.1 million for restaurant remodeling and $10.8 million for new restaurant expenditures. For the thirty-nine weeks ended September 28, 2016, capital expenditures totaled $26.5 million, including $1.6 million for restaurant remodeling and $20.8 million for new restaurant expenditures. Capital expenditures for the quarter and year-to-date periods exclude unpaid purchases of property and equipment.

Stock-Based Compensation	9 Months Ended
Stock-Based Compensation	Sep. 28, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	3. STOCK-BASED COMPENSATION At September 28, 2016, options to purchase 2,174,348 shares of common stock were outstanding, including 1,648,322 vested and 526,026 unvested. Unvested options vest over time, or upon our achieving annual financial goals. However, upon a change in control, the board may accelerate vesting. At September 28, 2016, 1,605,831 premium options remained outstanding. For the thirteen and thirty-nine weeks ended September 28, 2016, there were exercises of stock options for 32,386 and 147,726 shares, respectively. For the thirteen and thirty-nine weeks ended September 30, 2015, there were exercises of stock options for 18,340 and 863,247 shares, respectively. For the thirteen and thirty-nine weeks ended September 28, 2016, options were granted at the fair market value on the date of grant of 9,875 and 329,673, respectively. No options were granted in the thirteen and thirty-nine weeks ended September 30, 2015. At September 28, 2016, there were 36,752 unvested restricted shares outstanding. Restricted shares vest over time. At September 28, 2016, we had total unrecognized compensation expense of $1.8 million, related to unvested stock options and restricted shares, which we expect to recognize over a weighted-average period of 3.0 years. Total stock-based compensation expense was $105,000 and $244,000 for the thirteen and thirty-nine weeks ended September 28, 2016 and $165,000 and $608,000 for the thirteen and thirty-nine weeks ended September 30, 2015, respectively.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Credit Agreements	9 Months Ended
Credit Agreements	Sep. 28, 2016
Debt Disclosure [Abstract]
Credit Agreements	4. CREDIT AGREEMENTS On December 11, 2014, the Company refinanced its debt, with EPL, Intermediate, and Holdings entering into a credit agreement with Bank of America, N.A., as administrative agent, swingline lender, and letter of credit issuer, the lenders party thereto, and the other parties thereto, which provides for a $200 million five-year senior secured revolving facility (the “2014 Revolver”). The 2014 Revolver includes a sub limit of $15 million for letters of credit and a sub limit of $15 million for swingline loans. At September 28, 2016, $7.2 million of letters of credit and $107 million of the revolving line of credit were outstanding. The amount available under the revolving line of credit was $85.8 million at September 28, 2016. The 2014 Revolver will mature on or about December 11, 2019. Borrowings under the 2014 Revolver (other than any swingline loans) bear interest, at the borrower’s option, at rates based upon either LIBOR or a base rate, plus, for each rate, a margin determined in accordance with a lease-adjusted consolidated leverage ratio-based pricing grid. The base rate is calculated as the highest of (a) the federal funds rate plus 0.50%, (b) the prime rate of Bank of America, or (c) LIBOR plus 1.00%. For LIBOR loans, the margin is in the range of 1.75% to 2.50%, and for base rate loans the margin is in the range of 0.75% to 1.50%. The margin was initially set at 2.00% for LIBOR loans and at 1.00% for base rate loans until the delivery of financial statements and a compliance certificate for the first quarter of 2015. The interest rate range was 2.20% to 2.27% and 2.02% to 2.27% for the thirteen and thirty-nine weeks ended September 28, 2016, respectively. The 2014 Revolver includes a number of negative and financial covenants, including, among others, the following (all subject to certain exceptions): a maximum lease-adjusted consolidated leverage ratio covenant, a minimum consolidated fixed charge coverage ratio, and limitations on indebtedness, liens, investments, asset sales, mergers, consolidations, liquidations, dissolutions, restricted payments, and negative pledges. The 2014 Revolver also includes certain customary affirmative covenants and events of default. The Company was in compliance with all such covenants at September 28, 2016. See Note 1 for restrictions on the payment of dividends under the 2014 Revolver. Maturities There are no required principal payments prior to maturity for the 2014 Revolver. During the thirty-nine weeks ended September 28, 2016, the Company elected to pay down $16.0 million of outstanding borrowing on our 2014 Revolver, primarily from our cash flow from operations.

Other Accrued Expenses and Current Liabilities

9 Months Ended

Sep. 28, 2016

Payables And Accruals [Abstract]

Other Accrued Expenses and Current Liabilities

5. OTHER ACCRUED EXPENSES AND CURRENT LIABILITIES

Other accrued expenses and current liabilities consist of the following (in thousands):

	September 28, 2016		December 30, 2015
Accrued sales and property taxes	$	4,539	$	3,480
Income tax receivable agreement payable		4,197		7,609
Gift card liability		1,502		1,810
Other		3,665		3,227
Total other accrued expenses and current liabilities	$	13,903	$	16,126

Other Noncurrent Liabilities

9 Months Ended

Sep. 28, 2016

Payables And Accruals [Abstract]

Other Noncurrent Liabilities

6. OTHER NONCURRENT LIABILITIES

Other noncurrent liabilities consist of the following (in thousands):

	September 28, 2016		December 30, 2015
Deferred rent	$	7,765	$	6,611
Income tax receivable agreement payable		37,753		33,930
Other		2,521		2,826
Total other noncurrent liabilities	$	48,039	$	43,367

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 28, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. COMMITMENTS AND CONTINGENCIES Legal Matters On or about February 24, 2014, a former employee filed a class action in the Superior Court of the State of California, County of Orange, against EPL on behalf of all putative class members (all hourly employees from 2010 to the present) alleging certain violations of California labor laws, including failure to pay overtime compensation, failure to provide meal periods and rest breaks, and failure to provide itemized wage statements. The putative lead plaintiff’s requested remedies include compensatory and punitive damages, injunctive relief, disgorgement of profits, and reasonable attorneys’ fees and costs. No specific amount of damages sought was specified in the complaint. The parties have executed a Stipulation of Class Settlement and Release which has been submitted for court approval. Purported class actions alleging wage and hour violations are commonly filed against California employers, and we fully expect to have to defend against similar lawsuits in the future. Daniel Turocy, et al. v. El Pollo Loco Holdings, Inc., et al. (Case No. 8:15-cv-01343) was filed in the United States District Court for the Central District of California on August 24, 2015, and Ron Huston, et al. v. El Pollo Loco Holdings, Inc., et al. (Case No. 8:15-cv-01710) was filed in the United States District Court for the Central District of California on October 22, 2015. The two lawsuits have been consolidated, with co-lead plaintiffs and class counsel. A consolidated complaint was filed on January 29, 2016, on behalf of co-lead plaintiffs and others similarly situated, alleging violations of federal securities laws in connection with Holdings common stock purchased or otherwise acquired and the purchase of call options or the sale of put options, between May 1, 2015 and August 13, 2015 (the “Class Period”). The named defendants are Holdings; Stephen J. Sather, Laurance Roberts, and Edward J. Valle (collectively, the “Individual Defendants”); and Trimaran Pollo Partners, L.L.C., Trimaran Capital Partners, and Freeman Spogli & Co. (collectively, the “Controlling Shareholder Defendants”). Among other things, Plaintiffs allege that, in 2014 and early 2015, Holdings suffered losses due to rising labor costs in California and, in an attempt to mitigate the effects of such rising costs, removed a $5 value option from our menu, which resulted in a decrease in value-conscious store traffic. Plaintiffs further allege that during the Class Period, Holdings and the Individual Defendants made a series of materially false and misleading statements that concealed the effect that these factors were having on store sales growth, resulting in Holdings stock continuing to be traded at artificially inflated prices. As a result, Plaintiffs and other members of the putative class allegedly suffered damages in connection with their purchase of Holdings’ stock during the Class Period. In addition, Plaintiffs allege that the Individual Defendants and Controlling Shareholder Defendants had direct involvement in, and responsibility over, the operations of Holdings, and are presumed to have had, among other things, the power to control or influence the transactions giving rise to the alleged securities law violations. In both cases, Plaintiffs seek an unspecified amount of damages, as well as costs and expenses (including attorneys’ fees). On July 25, 2016, the Court issued an order granting, without prejudice, Holdings’ Motion to Dismiss plaintiff’s complaint for failure to state a claim. Plaintiffs were granted leave to amend their complaint, and filed an amended complaint on August 22, 2016. Defendants intend to vigorously defend against the claims asserted. In addition, on September 16, 2015, Holdings and certain of its officers and directors received an informal, non-public inquiry from the SEC requesting voluntary production of documents and information. All parties cooperated fully with the SEC's request. On July 15, 2016, Holdings was informed that the SEC was closing its inquiry as to all parties. On or about November 5, 2015, a purported Holdings shareholder filed a derivative complaint on behalf of Holdings in the Court of Chancery of the State of Delaware against certain Holdings officers, directors and Trimaran Pollo Partners, L.L.C. The derivative complaint alleges that these defendants breached their fiduciary duties to Holdings and were unjustly enriched when they sold shares of Holdings at artificially inflated prices due to alleged misrepresentations and omissions regarding EPL’s comparable store sales in the second quarter of 2015. The Holdings shareholder’s requested remedies include an award of compensatory damages to Holdings, as well as a court order to improve corporate governance by putting forward for stockholder vote certain resolutions for amendments to Holdings’ Bylaws or Certificate of Incorporation. The parties have stipulated to, which the court has ordered, a stay of these proceedings pending the outcome of Turocy v. El Pollo Loco Holdings, Inc., discussed above. A second purported Holdings shareholder filed a derivative complaint on or about September 23, 2016, allegedly on behalf of Holdings in the same venue naming the same defendants with substantially the same allegations arising from the same set of facts. We are also involved in various other claims and legal actions that arise in the ordinary course of business. We do not believe that the ultimate resolution of these other actions will have a material adverse effect on our financial position, results of operations, liquidity, or capital resources. A significant increase in the number of claims, or an increase in amounts owing under successful claims, could materially and adversely affect our business, financial condition, results of operations, and cash flows. Purchasing Commitments The Company has long-term beverage supply agreements with certain major beverage vendors. Pursuant to the terms of these arrangements, marketing rebates are provided to the Company and its franchisees from the beverage vendors based upon the dollar volume of purchases for system-wide restaurants which will vary according to their demand for beverage syrup and fluctuations in the market rates for beverage syrup. These contracts have terms extending into 2017 with an estimated Company obligation totaling $9.7 million as of September 28, 2016. At September 28, 2016, the Company’s total estimated commitment to purchase chicken was $13.4 million. Contingent Lease Obligations As a result of assigning the Company’s interest in obligations under real estate leases in connection with the sale of company-operated restaurants to some of the Company’s franchisees, the Company is contingently liable on five lease agreements. These leases have various terms, the latest of which expires in 2036. As of September 28, 2016, the potential amount of undiscounted payments the Company could be required to make in the event of non-payment by the primary lessee was $3.3 million. The present value of these potential payments discounted at the Company’s estimated pre-tax cost of debt at September 28, 2016 was $2.8 million. The Company’s franchisees are primarily liable on the leases. The Company has cross-default provisions with these franchisees that would put them in default of their franchise agreements in the event of non-payment under the leases. The Company believes that these cross-default provisions reduce the risk that payments will be required to be made under these leases. Accordingly, no liability has been recorded in the Company’s condensed consolidated financial statements related to these contingent liabilities. Employment Agreements The Company has employment agreements with four of the officers of the Company on an at will basis. These agreements provide for minimum salary levels, possible annual adjustments for cost-of-living changes, and incentive bonuses that are payable under certain business conditions. Indemnification Agreements The Company has entered into indemnification agreements with each of its current directors and executive officers. These agreements require the Company to indemnify these individuals to the fullest extent permitted under Delaware law against liabilities that may arise by reason of their service to the Company and to advance expenses incurred as a result of any proceeding against them as to which they could be indemnified. The Company also intends to enter into indemnification agreements with future directors and executive officers.

Net Income Per Share

9 Months Ended

Sep. 28, 2016

Earnings Per Share [Abstract]

Net Income Per Share

8. NET INCOME PER SHARE

Basic net income per share is calculated using the weighted-average number of shares of common stock outstanding during the thirteen and thirty-nine weeks ended September 28, 2016 and September 30, 2015. Diluted net income per share is calculated using the weighted-average number of shares of common stock outstanding and potentially dilutive during the period, using the treasury stock method.

Below are basic and diluted net income per share data for the periods indicated, which are in thousands except for per share data.

	Thirteen Weeks Ended				Thirty-Nine Weeks Ended
	September 28, 2016		September 30, 2015		September 28, 2016		September 30, 2015
Numerator:
Net income	$	5,211	$	4,666	$	17,921	$	18,688
Denominator:
Weighted-average shares outstanding—basic		38,415,189		38,275,317		38,331,400		37,837,610
Weighted-average shares outstanding—diluted		39,083,577		39,107,241		39,020,127		39,044,388
Net income per share—basic	$	0.14	$	0.12	$	0.47	$	0.49
Net income per share—diluted	$	0.13	$	0.12	$	0.46	$	0.48
Anti-dilutive securities not considered in diluted EPS calculation		451,325		—		451,325		—

Below is a reconciliation of basic and diluted share counts.

	Thirteen Weeks Ended				Thirty-Nine Weeks Ended
	September 28, 2016		September 30, 2015		September 28, 2016		September 30, 2015
Weighted-average shares outstanding— basic		38,415,189		38,275,317		38,331,400		37,837,610
Dilutive effect of stock options and restricted shares		668,388		831,924		688,727		1,206,778
Weighted-average shares outstanding— diluted		39,083,577		39,107,241		39,020,127		39,044,388

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 28, 2016
Related Party Transactions [Abstract]
Related Party Transactions	9. RELATED PARTY TRANSACTIONS Trimaran Pollo Partners, L.L.C. (“LLC”), owns approximately 43.5% of the Company’s outstanding common stock. This large position means that LLC and its majority owners—predecessors and affiliates of, and certain funds managed by, Trimaran Capital Partners and Freeman Spogli & Co. (collectively, “Trimaran” and “Freeman Spogli,” respectively)—possess significant influence when stockholders vote on matters such as election of directors, mergers, consolidations and acquisitions, the sale of all or substantially all of the Company’s assets, decisions affecting the Company’s capital structure, amendments to the Company’s certificate of incorporation or by-laws, and the Company’s winding up and dissolution. So long as LLC maintains at least 40% ownership, (i) any member of the board of directors may be removed at any time without cause by affirmative vote of a majority of the Company’s common stock, and (ii) stockholders representing 40% or greater ownership may cause special stockholder meetings to be called.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 28, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments necessary for a fair presentation of its financial position and results of operations and cash flows for the periods presented. Interim results of operations are not necessarily indicative of the results that may be achieved for the full year. The consolidated financial statements and related notes do not include all information and footnotes required by GAAP for annual reports. This quarterly report should be read in conjunction with the consolidated financial statements included in the Company’s annual report on Form 10-K for the year ended December 30, 2015. The Company uses a 52- or 53-week fiscal year ending on the last Wednesday of the calendar year. In a 52-week fiscal year, each quarter includes 13 weeks of operations; in a 53-week fiscal year, the first, second and third quarters each include 13 weeks of operations and the fourth quarter includes 14 weeks of operations. Every six or seven years a 53-week fiscal year occurs. Fiscal 2015 and 2016 are both 52-week years, ending on December 30, 2015 and December 28, 2016, respectively. Revenues, expenses, and other financial and operational figures may be elevated in a 53-week year. Holdings has no material assets or operations. Holdings and Holdings’ direct subsidiary, EPL Intermediate, Inc. (“Intermediate”), guarantee EPL’s 2014 Revolver (see Note 4) on a full and unconditional basis and Intermediate has no subsidiaries other than EPL. EPL is a separate and distinct legal entity, and has no obligation to make funds available to Intermediate. EPL and Intermediate may pay dividends to Intermediate and to Holdings, respectively. Under the 2014 Revolver, Holdings may not make certain payments such as cash dividends, except that it may, inter alia, (i) pay up to $1 million per year to repurchase or redeem qualified equity interests of Holdings held by past or present officers, directors, or employees (or their estates) of the Company upon death, disability, or termination of employment, (ii) pay under its income tax receivable agreement (the “TRA”), and, (iii) so long as no default or event of default has occurred and is continuing, (a) make non-cash repurchases of equity interests in connection with the exercise of stock options by directors and officers, provided that those equity interests represent a portion of the consideration of the exercise price of those stock options, (b) pay up to $2.5 million per year pursuant to stock option plans, employment agreements, or incentive plans, (c) make up to $5 million in other restricted payments per year, and (d) make other restricted payments, provided that such payments would not cause, in each case, on a pro forma basis, (x) its lease-adjusted consolidated leverage ratio to equal or exceed 4.25 times and (y) its consolidated fixed charge coverage ratio to be less than 1.75 times.
Principles of Consolidation	Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of Holdings and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and revenue and expenses during the period reported. Actual results could materially differ from those estimates. The Company’s significant estimates include estimates for impairment of goodwill, intangible assets and property and equipment, insurance reserves, lease termination liabilities, closed store reserves, stock-based compensation, income tax receivable agreement liability, and income tax valuation allowances.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly-liquid instruments with a maturity of three months or less at the date of purchase to be cash equivalents.
Restricted Cash	Restricted Cash The Company’s restricted cash represents cash collateral to one commercial bank for Company credit cards.
Liquidity	Liquidity The Company’s principal liquidity requirements are to service our debt and to meet capital expenditure needs. At September 28, 2016, the Company’s total debt (including capital lease liabilities) was $107.5 million. The Company’s ability to make payments on its indebtedness and to fund planned capital expenditures depends on available cash and on its ability to generate adequate cash flows in the future, which, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory, and other factors that are beyond the Company’s control. Based on current operations, the Company believes that its cash flow from operations, available cash of $6.5 million at September 28, 2016, and available borrowings under the 2014 Revolver (which availability was approximately $85.8 million at September 28, 2016) will be adequate to meet the Company’s liquidity needs for the next 12 months.
Gain on Recovery of Insurance Proceeds	Gain on Recovery of Insurance Proceeds In November 2015, one of the Company’s restaurants incurred damage resulting from a fire. During the thirty-nine weeks ended September 28, 2016, we incurred costs directly related to the fire of $48,000, disposed of an additional $87,000 of assets and recognized gains of $741,000, related to the reimbursement of property and equipment and expenses incurred and $502,000 related to the reimbursement of lost profits. The reimbursement of lost profits is included in the accompanying consolidated statement of operations, for the thirteen and thirty-nine weeks ended September 28, 2016, as a reduction of Company restaurant expenses. The Company received from the insurance company cash of $1,000,000 during the thirty-nine weeks ended September 28, 2016 and $354,000, net of a $10,000 insurance deductible, on October 5, 2016. The $354,000 is included in accounts and other receivables in the condensed consolidated balance sheet as of September 28, 2016. In 2015, the Company disposed of $111,000 of assets related to the fire. The restaurant was reopened for business on March 14, 2016.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 addresses how certain cash receipts and cash payments are presented and classified in the statement of cash flows under Topic 230, Statement of Cash Flow, and other Topics. ASU 2016-15 is effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606) – Narrow-Scope Improvements and Practical Expedients. This ASU is intended to clarify two aspects of Topic 606: first, assessing the collectability criterion, options for the presentation of sales and similar taxes, noncash consideration, transition contract modifications, transition contract completion and secondly, technical corrections. The amendments in this update are effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods, and early application is permitted, but no earlier than fiscal years beginning after December 16, 2016. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606) – Identifying Performance Obligations and Licensing. This ASU is intended to clarify two aspects of Topic 606: identifying performance obligations and licensing implementation guidance. The amendments in this update are effective for financial statements issued for annual periods beginning after December 15, 2017, including interim periods within those annual periods, and early application is permitted, but no earlier than fiscal years beginning after December 16, 2016. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation – Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which is intended to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for annual periods beginning after December 15, 2016, and interim periods therein. Early application is permitted. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, “Leases.” The new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, "Financial Instruments – Overall: Recognition and Measurement of Financial Assets and Financial Liabilities." The pronouncement requires equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income, requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes, requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset, and eliminates the requirement for public business entities to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost. These changes become effective for the Company's fiscal year beginning December 28, 2017 and interim periods within that fiscal year. The Company is currently assessing the impact of this ASU on our consolidated financial statements. In November 2015, the FASB issued ASU No. 2015-17, “Income Taxes” which requires that deferred tax liabilities and assets be classified as noncurrent in a classified balance sheet. Prior to the issuance of the standard, deferred tax liabilities and assets were required to be separately classified into a current amount and a noncurrent amount in the balance sheet. The new accounting guidance represents a change in accounting principle and the standard is required to be adopted in annual periods beginning after December 15, 2016. After the adoption of this ASU all deferred tax assets and liabilities will be classified as noncurrent on the consolidated balance sheet. In July 2015, the FASB issued ASU No. 2015-11, “Inventory (Topic 330).” The pronouncement was issued to simplify the measurement of inventory and changes the measurement from lower of cost or market to lower of cost and net realizable value. This pronouncement is effective for reporting periods beginning after December 15, 2016. The adoption of ASU 2015-11 is not expected to have a significant impact on the Company’s consolidated financial position or results of operations. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (ASU 2014-09)”, which supersedes nearly all existing revenue recognition guidance under GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing GAAP. The revised revenue standard is effective for public entities for annual periods beginning after December 15, 2017, and interim periods therein, using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). The Company is currently assessing the impact of this ASU on our consolidated financial statements. In August 2014, the FASB issued ASU No. 2014-15, Going Concern (“ASU 2014-15”). ASU 2014-15 provides GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. The standard will be effective for annual periods ending after December 15, 2016, and interim periods within annual periods beginning after December 15, 2016. Early application is permitted for annual or interim reporting periods for which the financial statements have not previously been issued. Upon adoption the Company will use the guidance in ASU 2014-15 to assess going concern.
Subsequent Events	Subsequent Events Subsequent to September 28, 2016, the Company opened 4 new restaurants and made a $3.0 million pre-payment on the 2014 Revolver. On October 3, 2016, the Company announced a two unit franchise development agreement with Listo Way Group LLC to develop El Pollo Loco restaurants in Lafayette, Louisiana. On October 5, 2016, the Company received $354,000 in insurance proceeds related to damage resulting from a fire at one of the Company’s restaurants. On November 1, 2016, the Company amended the letters of credit related to the 2014 Revolver, thereby increasing the outstanding amount to $8.0 million. The Company evaluated subsequent events that have occurred after September 28, 2016, and determined that there were no other events or transactions occurring during this reporting period that require recognition or disclosure in the condensed consolidated financial statements.
Concentration of Risk	Concentration of Risk Cash and cash equivalents are maintained at financial institutions and, at times, balances may exceed federally-insured limits. The Company has never experienced any losses related to these balances. The Company had no suppliers for which amounts due at September 28, 2016 totaled greater than 10% of the Company’s accounts payable. As of December 30, 2015, the Company had two different suppliers for which amounts totaled 12% and 11% of the Company’s accounts payable. Purchases from the Company’s largest supplier totaled 33% for the thirteen weeks ended September 28, 2016, and 37% for the thirteen weeks ended September 30, 2015, of the Company’s purchases. Purchases from the Company’s largest supplier totaled 33% for the thirty-nine weeks ended September 28, 2016, and 37% for the thirty-nine weeks ended September 30, 2015, of the Company’s purchases. Company-operated and franchised restaurants in the greater Los Angeles area generated, in the aggregate, approximately 75% and 79% of total revenue for both the thirteen and thirty-nine weeks ended September 28, 2016 and September 30, 2015, respectively.
Goodwill and Indefinite Lived Intangible Assets	Goodwill and Indefinite Lived Intangible Assets The Company’s indefinite lived intangible assets consist of trademarks. Goodwill represents the excess of cost over fair value of net identified assets acquired in business combinations accounted for under the purchase method. The Company does not amortize its goodwill and indefinite lived intangible assets. Goodwill resulted from historical acquisitions. Upon the sale of a restaurant, the Company evaluates whether there is a decrement of goodwill. The amount of goodwill included in the cost basis of the asset sold is determined based on the relative fair value of the portion of the reporting unit disposed of compared to the fair value of the reporting unit retained. The Company performs annual impairment tests for goodwill during the fourth fiscal quarter of each year, or more frequently if impairment indicators arise. The Company reviews goodwill for impairment utilizing either a qualitative assessment or a two-step process. If the Company decides that it is appropriate to perform a qualitative assessment and concludes that the fair value of a reporting unit more likely than not exceeds its carrying value, no further evaluation is necessary. If the Company performs the two-step process, the first step of the goodwill impairment test is used to identify potential impairment by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is considered not impaired and the second step of the impairment test is unnecessary. If the carrying amount of a reporting unit exceeds its fair value, the second step is performed to measure the amount of impairment by comparing the carrying amount of the goodwill to a determination of the implied value of the goodwill. If the carrying amount of goodwill is greater than the implied value, an impairment charge is recognized for the difference. The Company performs annual impairment tests for indefinite lived intangible assets during the fourth fiscal quarter of each year, or more frequently if impairment indicators arise. An impairment test consists of either a qualitative assessment or a comparison of the fair value of an intangible asset with its carrying amount. The excess of the carrying amount of an intangible asset over its fair value is its impairment loss. The assumptions used in the estimate of fair value are generally consistent with the past performance of the Company’s reporting segment and are also consistent with the projections and assumptions that are used in current operating plans. These assumptions are subject to change as a result of changing economic and competitive conditions. The Company did not identify any indicators of potential impairment during the thirteen and thirty-nine weeks ended September 28, 2016, and therefore did not perform any impairment review, nor did the Company record any impairment.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment on a restaurant-by-restaurant basis whenever events or changes in circumstances indicate that the carrying value of certain assets may not be recoverable. If the Company concludes that the carrying value of certain assets will not be recovered based on expected undiscounted future cash flows, an impairment write-down is recorded to reduce the assets to their estimated fair value. The fair value is measured on a nonrecurring basis using unobservable (Level 3) inputs. Based on the results of the analysis, the Company recorded a non-cash impairment charge of $2.4 million for the thirteen and thirty-nine weeks ended September 28, 2016, related to non-recoverable assets of two restaurants in Arizona and Texas. The Company continues to monitor the recoverability of the carrying value of the assets of several other restaurants, including new restaurants opened in 2015 in Texas.
Income Taxes	Income Taxes The provision for income taxes, income taxes payable and deferred income taxes is determined using the asset and liability method. Deferred tax assets and liabilities are determined based on temporary differences between the financial carrying amounts and the tax bases of assets and liabilities using enacted tax rates in effect in the years in which the temporary differences are expected to reverse. On a periodic basis, the Company assesses the probability that its net deferred tax assets, if any, will be recovered. If, after evaluating all of the positive and negative evidence, a conclusion is made that it is more likely than not that some portion or all of the net deferred tax assets will not be recovered, a valuation allowance is provided by charging to tax expense to reserve the portion of deferred tax assets which are not expect to be realized. The Company reviews its filing positions for all open tax years in all U.S. federal and state jurisdictions where the Company is required to file. When there are uncertainties related to potential income tax benefits, in order to qualify for recognition, the position the Company takes has to have at least a “more likely than not” chance of being sustained (based on the position’s technical merits) upon challenge by the respective authorities. The term “more likely than not” means a likelihood of more than 50 percent. Otherwise, the Company may not recognize any of the potential tax benefit associated with the position. The Company recognizes a benefit for a tax position that meets the “more likely than not” criterion at the largest amount of tax benefit that is greater than 50 percent likely of being realized upon its effective resolution. Unrecognized tax benefits involve management’s judgment regarding the likelihood of the benefit being sustained. The final resolution of uncertain tax positions could result in adjustments to recorded amounts and may affect our results of operations, financial position, and cash flows. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company had no accrual for interest or penalties at September 28, 2016 or at December 30, 2015, and did not recognize interest or penalties during the thirteen or thirty-nine weeks ended September 28, 2016 or September 30, 2015, since there were no material unrecognized tax benefits. Management believes no material changes to the amount of unrecognized tax benefits will occur within the next twelve months. On July 30, 2014, the Company entered into the TRA. The TRA calls for the Company to pay to its pre-IPO stockholders 85% of the savings in cash that the Company realizes in its taxes as a result of utilizing its net operating losses and other tax attributes attributable to preceding periods.

Property and Equipment (Tables)

9 Months Ended

Sep. 28, 2016

Property Plant And Equipment [Abstract]

Schedule of Costs and Related Accumulated Depreciation and Amortization of Major Classes of Property

The costs and related accumulated depreciation and amortization of major classes of property are as follows (in thousands):

	September 28, 2016			December 30, 2015
Land	$	12,323		$	12,323
Buildings and improvements		121,875			111,349
Other property and equipment		64,065			58,525
Construction in progress		12,803			4,717
		211,066			186,914
Less: accumulated depreciation and amortization		(93,807	)		(84,493	)
	$	117,259		$	102,421

Other Accrued Expenses and Current Liabilities (Tables)

9 Months Ended

Sep. 28, 2016

Payables And Accruals [Abstract]

Schedule of Other Accrued Expenses and Current Liabilities

Other accrued expenses and current liabilities consist of the following (in thousands):

	September 28, 2016		December 30, 2015
Accrued sales and property taxes	$	4,539	$	3,480
Income tax receivable agreement payable		4,197		7,609
Gift card liability		1,502		1,810
Other		3,665		3,227
Total other accrued expenses and current liabilities	$	13,903	$	16,126

Other Noncurrent Liabilities (Tables)

9 Months Ended

Sep. 28, 2016

Payables And Accruals [Abstract]

Schedule of Other Noncurrent Liabilities

Other noncurrent liabilities consist of the following (in thousands):

	September 28, 2016		December 30, 2015
Deferred rent	$	7,765	$	6,611
Income tax receivable agreement payable		37,753		33,930
Other		2,521		2,826
Total other noncurrent liabilities	$	48,039	$	43,367

Net Income Per Share (Tables)

9 Months Ended

Sep. 28, 2016

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Income per Share

Below are basic and diluted net income per share data for the periods indicated, which are in thousands except for per share data.

	Thirteen Weeks Ended				Thirty-Nine Weeks Ended
	September 28, 2016		September 30, 2015		September 28, 2016		September 30, 2015
Numerator:
Net income	$	5,211	$	4,666	$	17,921	$	18,688
Denominator:
Weighted-average shares outstanding—basic		38,415,189		38,275,317		38,331,400		37,837,610
Weighted-average shares outstanding—diluted		39,083,577		39,107,241		39,020,127		39,044,388
Net income per share—basic	$	0.14	$	0.12	$	0.47	$	0.49
Net income per share—diluted	$	0.13	$	0.12	$	0.46	$	0.48
Anti-dilutive securities not considered in diluted EPS calculation		451,325		—		451,325		—

Schedule of Reconciliation of Basic and Diluted Share Counts

Below is a reconciliation of basic and diluted share counts.

	Thirteen Weeks Ended				Thirty-Nine Weeks Ended
	September 28, 2016		September 30, 2015		September 28, 2016		September 30, 2015
Weighted-average shares outstanding— basic		38,415,189		38,275,317		38,331,400		37,837,610
Dilutive effect of stock options and restricted shares		668,388		831,924		688,727		1,206,778
Weighted-average shares outstanding— diluted		39,083,577		39,107,241		39,020,127		39,044,388

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail)			1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 05, 2016 USD ($) Restaurants	Jul. 30, 2014	Nov. 30, 2015 Restaurants	Sep. 28, 2016 USD ($) Restaurants	Sep. 30, 2015 USD ($)	Sep. 28, 2016 USD ($) Segment Restaurants Supplier	Sep. 30, 2015 USD ($)	Dec. 30, 2015 USD ($) Supplier	Nov. 01, 2016 USD ($)	Oct. 03, 2016 Restaurants	Sep. 29, 2016 USD ($) Restaurants	Dec. 31, 2014 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segment						1
Restricted dividend payments, description						Under the 2014 Revolver, Holdings may not make certain payments such as cash dividends, except that it may, inter alia, (i) pay up to $1 million per year to repurchase or redeem qualified equity interests of Holdings held by past or present officers, directors, or employees (or their estates) of the Company upon death, disability, or termination of employment, (ii) pay under its income tax receivable agreement (the “TRA”), and, (iii) so long as no default or event of default has occurred and is continuing, (a) make non-cash repurchases of equity interests in connection with the exercise of stock options by directors and officers, provided that those equity interests represent a portion of the consideration of the exercise price of those stock options, (b) pay up to $2.5 million per year pursuant to stock option plans, employment agreements, or incentive plans, (c) make up to $5 million in other restricted payments per year, and (d) make other restricted payments, provided that such payments would not cause, in each case, on a pro forma basis, (x) its lease-adjusted consolidated leverage ratio to equal or exceed 4.25 times and (y) its consolidated fixed charge coverage ratio to be less than 1.75 times.
Total amount of outstanding debt				$ 107,500,000		$ 107,500,000
Cash available				6,529,000	$ 8,207,000	6,529,000	$ 8,207,000	$ 6,101,000				$ 11,499,000
Number of restaurants damaged \| Restaurants			1
Costs incurred directly related to fire						48,000
Disposition of assets related to fire				87,000		87,000		111,000
Gain on recovery of insurance proceeds, related to the reimbursement of property and equipment and expenses incurred				(148,000)		741,000
Gain on recovery of insurance proceeds, related to the reimbursement of lost profits				502,000		502,000
Amount received from insurance company in cash						1,000,000
Asset impairment charges				2,400,000		2,400,000
Unrecognized tax benefits, accrual of interest or penalties				0		0		$ 0
Unrecognized tax benefits, interest or penalties expenses				0	$ 0	0	$ 0
Percentage of cash savings in taxes realized as a result of utilizing net operating losses payable to pre-IPO stockholders		85.00%
Indefinite-lived Intangible Assets [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Asset impairment charges				$ 0		$ 0
Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of suppliers \| Supplier						0		2
Supplier Two [Member] \| Accounts Payable [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration								12.00%
Supplier Three [Member] \| Accounts Payable [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration								11.00%
Largest Supplier One [Member] \| Purchased [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration				33.00%	37.00%	33.00%	37.00%
The Greater Los Angeles Area [Member] \| Revenue [Member] \| Geographic Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration				75.00%	79.00%	75.00%	79.00%
Subsequent Event [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants											4
Number of restaurants damaged \| Restaurants	1
Amount received from insurance company in cash	$ 354,000
Insurance deductible	$ 10,000
Letters of credit, Increased outstanding amount									$ 8,000,000
Accounts and Other Receivables [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Cash received from insurance company included in the accounts and other receivables				$ 354,000		$ 354,000
Senior Secured Revolving Credit Facility [Member] \| Subsequent Event [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Pre-payment for new restaurant											$ 3,000,000
2013 First Lien Credit Agreement [Member] \| Senior Secured Revolving Credit Facility [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Amount of borrowings available				$ 85,800,000		$ 85,800,000
Entity Operated Units [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants				193		193
Franchised Units [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants				253		253
Franchised Units [Member] \| Subsequent Event [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants										2

Property and Equipment - Schedule of Costs and Related Accumulated Depreciation and Amortization of Major Classes of Property (Detail) - USD ($) $ in Thousands	Sep. 28, 2016	Dec. 30, 2015
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 211,066	$ 186,914
Less: accumulated depreciation and amortization	(93,807)	(84,493)
Property and equipment, net	117,259	102,421
Land [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	12,323	12,323
Buildings and Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	121,875	111,349
Other Property and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	64,065	58,525
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 12,803	$ 4,717

Property and Equipment - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015	Sep. 28, 2016	Sep. 30, 2015	Dec. 30, 2015
Property Plant And Equipment [Abstract]
Depreciation expense	$ 4.1	$ 3.3	$ 11.8	$ 9.6
Gross value of assets under capital leases for buildings and improvements	1.6		1.6		$ 1.6
Accumulated depreciation of assets under capital leases	1.5		1.5		$ 1.5
Capital expenditures	12.1		26.5
Capital expenditures for restaurant remodeling	0.1		1.6
Capital expenditures for new restaurants	$ 10.8		$ 20.8

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015	Sep. 28, 2016	Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, options outstanding	2,174,348		2,174,348
Common stock, options vested			1,648,322
Common stock, options unvested	526,026		526,026
Stock options exercised	32,386	18,340	147,726	863,247
Number of options granted at fair market value	9,875	0	329,673	0
Unrecognized compensation expense	$ 1,800		$ 1,800
Unrecognized compensation expense, recognition period			3 years
Stock-based compensation expense	$ 105	$ 165	$ 244	$ 608
Premium Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, options outstanding	1,605,831		1,605,831
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested restricted shares outstanding	36,752		36,752

Credit Agreements - Additional Information (Detail) - USD ($)		3 Months Ended	9 Months Ended
	Dec. 11, 2014	Sep. 28, 2016	Sep. 28, 2016
Debt Instrument [Line Items]
Revolving credit facility maturity period			Dec. 11, 2019
Debt instrument basis percentage			1.00%
Interest rate description			(a) the federal funds rate plus 0.50%, (b) the prime rate of Bank of America, or (c) LIBOR plus 1.00%. For LIBOR loans, the margin is in the range of 1.75% to 2.50%, and for base rate loans the margin is in the range of 0.75% to 1.50%. The margin was initially set at 2.00% for LIBOR loans and at 1.00% for base rate loans until the delivery of financial statements and a compliance certificate for the first quarter of 2015. The interest rate range was 2.20% to 2.27% and 2.02% to 2.27% for the thirteen and thirty-nine weeks ended September 28, 2016, respectively.
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal payments prior to maturity			$ 0
Debt instrument, periodic payment			$ 16,000,000
Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		2.20%	2.02%
Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		2.27%	2.27%
Federal Funds Rate [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			0.50%
Base Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			0.75%
Base Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			1.50%
Initial Margin Rate [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			2.00%
LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			1.00%
LIBOR [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			1.75%
LIBOR [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument basis percentage			2.50%
2014 Credit Agreement [Member]
Debt Instrument [Line Items]
Senior secured revolving facility	$ 200,000,000
Senior secured revolving facility term	5 years
Letters of credit outstanding		$ 7,200,000	$ 7,200,000
Revolving line of credit		107,000,000	107,000,000
Amount of borrowings available		$ 85,800,000	$ 85,800,000
Swing Line Loans [Member] \| 2014 Credit Agreement [Member]
Debt Instrument [Line Items]
Sub limit of revolving facility	$ 15,000,000
Letter of Credit [Member] \| 2014 Credit Agreement [Member]
Debt Instrument [Line Items]
Sub limit of revolving facility	$ 15,000,000

Other Accrued Expenses and Current Liabilities - Schedule of Other Accrued Expenses and Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 28, 2016	Dec. 30, 2015
Other Liabilities Disclosure [Abstract]
Accrued sales and property taxes	$ 4,539	$ 3,480
Income tax receivable agreement payable	4,197	7,609
Gift card liability	1,502	1,810
Other	3,665	3,227
Total other accrued expenses and current liabilities	$ 13,903	$ 16,126

Other Noncurrent Liabilities - Schedule of Other Noncurrent Liabilities (Detail) - USD ($) $ in Thousands	Sep. 28, 2016	Dec. 30, 2015
Other Liabilities Noncurrent [Abstract]
Deferred rent	$ 7,765	$ 6,611
Income tax receivable agreement payable	37,753	33,930
Other	2,521	2,826
Total other noncurrent liabilities	$ 48,039	$ 43,367

Commitments and Contingencies - Additional Information (Detail)	9 Months Ended
	Sep. 28, 2016 USD ($) Lawsuit Lease Agreement
Other Commitments [Line Items]
Date of class action filed in court	On or about February 24, 2014
Number of lawsuits consolidated \| Lawsuit	2
Call option value reduced from menu	$ 5
Officers [Member]
Other Commitments [Line Items]
Number of at-will employment agreements \| Agreement	4
Property Lease Guarantee [Member]
Other Commitments [Line Items]
Number of leases assigned to franchisees \| Lease	5
Latest lease expiration year	2036
Contingent lease obligations, maximum exposure	$ 3,300,000
Contingent lease obligations, maximum exposure, if discounted at estimated pre-tax cost of debt	2,800,000
Beverage [Member]
Other Commitments [Line Items]
Purchase commitments, estimated obligations	9,700,000
Chicken Acquisition Corp [Member]
Other Commitments [Line Items]
Purchase commitments, estimated obligations	$ 13,400,000

Net Income Per Share - Computation of Basic and Diluted Net Income per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015	Sep. 28, 2016	Sep. 30, 2015
Numerator:
Net income	$ 5,211	$ 4,666	$ 17,921	$ 18,688
Denominator:
Weighted-average shares outstanding—basic	38,415,189	38,275,317	38,331,400	37,837,610
Weighted-average shares outstanding—diluted	39,083,577	39,107,241	39,020,127	39,044,388
Net income per share—basic	$ 0.14	$ 0.12	$ 0.47	$ 0.49
Net income per share—diluted	$ 0.13	$ 0.12	$ 0.46	$ 0.48
Anti-dilutive securities not considered in diluted EPS calculation	451,325		451,325

Net Income Per Share - Schedule of Reconciliation of Basic and Diluted Share Counts (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 28, 2016	Sep. 30, 2015	Sep. 28, 2016	Sep. 30, 2015
Earnings Per Share [Abstract]
Weighted-average shares outstanding—basic	38,415,189	38,275,317	38,331,400	37,837,610
Dilutive effect of stock options and restricted shares	668,388	831,924	688,727	1,206,778
Weighted-average shares outstanding— diluted	39,083,577	39,107,241	39,020,127	39,044,388

Related Party Transactions - Additional Information (Detail) - Trimaran Pollo Partners, LLC [Member]	9 Months Ended
	Sep. 28, 2016
Related Party Transaction [Line Items]
Company's outstanding common stock owned by Trimaran Pollo Partners, L.L.C.	43.50%
Ownership description	So long as LLC maintains at least 40% ownership, (i) any member of the board of directors may be removed at any time without cause by affirmative vote of a majority of the Company’s common stock, and (ii) stockholders representing 40% or greater ownership may cause special stockholder meetings to be called.
Minimum [Member]
Related Party Transaction [Line Items]
Outstanding membership interest, percentage	40.00%
Ownership percentage by stockholders	40.00%