Accounting Policies [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Adjustments Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Balances without adoption of Topic 606 Calculated under Revenue Guidance in Effect before Topic 606 [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Franchise revenue Franchise [Member] Franchise advertising fee revenue Franchise Advertising Fee [Member] Franchise Advertising Fee [Member] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Revenue Revenues [Abstract] Company-operated restaurant revenue Revenue from Contract with Customer, Excluding Assessed Tax Cost of operations Cost of Goods and Services Sold [Abstract] Franchise expenses Franchisor Costs Total expenses Costs and Expenses Loss from operations Operating Income (Loss) Loss before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Net (loss) income Net Income (Loss) Attributable to Parent Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Chicken Acquisition Corp Chicken Acquisition Corp [Member] Chicken Acquisition Corp [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility Credit Facility [Domain] Revolving Credit Facility Revolving Credit Facility [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 2018 Credit Agreement Credit Agreement Two Thousand Eighteen [Member] Credit Agreement Two Thousand Eighteen [Member] Franchisor Disclosure Franchisor Disclosure [Axis] Franchisor Disclosure Franchisor Disclosure [Domain] Company-operated Entity Operated Units [Member] Franchised Franchised Units [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] The Greater Los Angeles Area Los Angeles [Member] Information pertaining to Los Angeles. Philippines PHILIPPINES Debt Instrument [Line Items] Debt Instrument [Line Items] Number of restaurants Number of Restaurants Ownership interest Equity Method Investment, Ownership Percentage Senior secured revolving facility Line of Credit Facility, Maximum Borrowing Capacity Senior secured revolving facility term Debt Instrument, Term Maximum annual repurchase or redemption of qualified entity interests Debt Instrument, Restrictive Covenants, Maximum Annual Repurchase or Redemption of Qualified Entity Interests Debt Instrument, Restrictive Covenants, Maximum Annual Repurchase or Redemption of Qualified Entity Interests Restrictive covenants, maximum annual repurchase, redemption or acquired equity interests, up to Debt Instrument, Restrictive Covenants, Maximum Annual Redemption, Repurchase, Acquired Equity Interests Debt Instrument, Restrictive Covenants, Maximum Annual Redemption, Repurchase, Acquired Equity Interests Maximum annual payment for stock option plans, employment agreements and incentive plans Debt Instrument, Restrictive Covenants, Maximum Annual Payment For Stock Option Plans, Employment Agreements and Incentive Plans Debt Instrument, Restrictive Covenants, Maximum Annual Payment For Stock Option Plans, Employment Agreements and Incentive Plans Maximum annual payment for other restricted payments Debt Instrument, Restrictive Covenants, Maximum Annual Payment For Other Restricted Payments Debt Instrument, Restrictive Covenants, Maximum Annual Payment For Other Restricted Payments Maximum leverage ratio Debt Instrument, Covenant Description, Maximum Leverage Ratio Debt Instrument, Covenant Description, Maximum Leverage Ratio Number of operating segments Number of Operating Segments Authorized amount under share repurchase agreement Stock Repurchase Program, Authorized Amount Number of shares repurchased (shares) Treasury Stock, Shares, Acquired Value of shares repurchased Treasury Stock, Value, Acquired, Cost Method Postemployment Benefits [Abstract] Defined Contribution Plan [Table] Defined Contribution Plan [Table] Defined Contribution Plan, Employer Matching Contribution Defined Contribution Plan, Employer Matching Contribution [Axis] Defined Contribution Plan, Employer Matching Contribution [Axis] Defined Contribution Plan, Employer Matching Contribution [Domain] Defined Contribution Plan, Employer Matching Contribution [Domain] [Domain] for Defined Contribution Plan, Employer Matching Contribution [Axis] First 3% of Annual Qualified Compensation Scenario1 [Member] Scenario 1. Next 2 % of Annual Qualified Compensation Scenario2 [Member] Scenario 2. Defined Contribution Plan Disclosure [Line Items] Defined Contribution Plan Disclosure [Line Items] Qualified compensation of employees that may be contributed, maximum Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Employer's matching contribution Defined Contribution Plan, Employer Matching Contribution, Percent of Match Percentage of employees' annual qualified compensation matched Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Benefit contribution Defined Contribution Plan, Cost Document And Entity Information [Abstract] Document And Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Filer Category Entity Filer Category Emerging Growth Company Entity Emerging Growth Company Small Business Entity Entity Small Business Entity Ex Transition Period Entity Ex Transition Period Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Public Float Entity Public Float Property, Plant and Equipment [Abstract] Property and Equipment Property, Plant and Equipment Disclosure [Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contracts with Customers Revenue from Contract with Customer [Text Block] Commitments and Contingencies Disclosure [Abstract] Other Commitments [Table] Other Commitments [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Elliott Olvera, et al v. El Pollo Loco, Inc., et al Elliott Olvera, et al v. El Pollo Loco, Inc., et al [Member] Elliott Olvera, et al v. El Pollo Loco, Inc., et al [Member] Daniel Turocy, et al. and Ron Huston et al v. El Pollo Loco Holdings, Inc., et al Daniel Turocy, et al. and Ron Huston et al v. El Pollo Loco Holdings, Inc., et al [Member] Daniel Turocy, et al. and Ron Huston et al v. El Pollo Loco Holdings, Inc., et al [Member] Janice P. Handlers-Bryman and Michael D. Bryman v. El Pollo Loco, Inc Janice P. Handlers-Bryman and Michael D. Bryman v. El Pollo Loco, Inc [Member] Janice P. Handlers-Bryman and Michael D. Bryman v. El Pollo Loco, Inc [Member] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Impact Damages Impact Damages [Member] Impact Damages [Member] Lost Opportunity Damages Lost Opportunity Damages [Member] Lost Opportunity Damages [Member] Total Damages Total Damages [Member] Total Damages [Member] Range Range [Axis] Range Range [Domain] Minimum Minimum [Member] Category of Item Purchased Category of Item Purchased [Axis] Long-term Purchase Commitment, Category of Item Purchased Long-term Purchase Commitment, Category of Item Purchased [Domain] Chicken Acquisition Corp Chicken [Member] Chicken. Guarantor Obligations, Nature Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature Guarantor Obligations, Nature [Domain] Property Lease Guarantee Property Lease Guarantee [Member] Title of Individual Title of Individual [Axis] Relationship to Entity Relationship to Entity [Domain] Officers Officer [Member] Other Commitments [Line Items] Other Commitments [Line Items] Accrual associated with loss contingencies Loss Contingency Accrual Number of lawsuits consolidated Number Of Lawsuits Number of lawsuits. Value of damages awarded Loss Contingency, Damages Awarded, Value Payments made to plaintiff's attorneys Professional Fees Purchase commitments, estimated obligations Purchase Obligation Number of leases assigned to franchisees Number Of Leases Number of leases. Contingent lease obligations, maximum exposure Guarantor Obligations, Maximum Exposure, Undiscounted Contingent lease obligations, maximum exposure, if discounted at estimated pre-tax cost of debt Guarantee Obligations Maximum Net Exposure Guarantee obligations maximum net exposure. Number of at-will employment agreements Number Of Employment Agreements Number of employment agreements. Leases [Abstract] Future Lease Payments Due [Table] Future Lease Payments Due [Table] Future Lease Payments Due [Table] Maximum Maximum [Member] Future Lease Payments Due [Line Items] Future Lease Payments Due [Line Items] Future Lease Payments Due [Line Items] Capital Leases, Minimum Lease Payments Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] December 25, 2019 Capital Leases, Future Minimum Payments Due, Next Twelve Months December 30, 2020 Capital Leases, Future Minimum Payments Due in Two Years December 29, 2021 Capital Leases, Future Minimum Payments Due in Three Years December 28, 2022 Capital Leases, Future Minimum Payments Due in Four Years December 28, 2023 Capital Leases, Future Minimum Payments Due in Five Years Thereafter Capital Leases, Future Minimum Payments Due Thereafter Total Capital Leases, Future Minimum Payments Due Less: imputed interest (11.0% to 11.1%) Capital Leases, Future Minimum Payments, Interest Included in Payments Imputed interest rate Capital Leases of Lessee, Contingent Rentals, Basis Spread on Variable Rate Present value of capital lease obligations Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments Less: current maturities Capital Lease Obligations, Current Noncurrent portion Capital Lease Obligations, Noncurrent Operating Leases, Minimum Lease Payments Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] December 25, 2019 Operating Leases, Future Minimum Payments Due, Next Twelve Months December 30, 2020 Operating Leases, Future Minimum Payments, Due in Two Years December 29, 2021 Operating Leases, Future Minimum Payments, Due in Three Years December 28, 2022 Operating Leases, Future Minimum Payments, Due in Four Years December 28, 2023 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total Operating Leases, Future Minimum Payments Due Operating Leases, Minimum Sublease Income Operating Leases, Income Statement, Lease Revenue [Abstract] December 25, 2019 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months December 30, 2020 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Two Years Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Two Years December 29, 2021 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Three Years Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Three Years December 28, 2022 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Four Years Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Four Years December 28, 2023 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Five Years Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Five Years Thereafter Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter Total Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals Operating Leases, Future Minimum Payments Receivable [Abstract] Operating Leases, Future Minimum Payments Receivable [Abstract] December 25, 2019 Operating Leases, Future Minimum Payments Receivable, Current December 30, 2020 Operating Leases, Future Minimum Payments Receivable, in Two Years December 29, 2021 Operating Leases, Future Minimum Payments Receivable, in Three Years December 28, 2022 Operating Leases, Future Minimum Payments Receivable, in Four Years December 28, 2023 Operating Leases, Future Minimum Payments Receivable, in Five Years Thereafter Operating Leases, Future Minimum Payments Receivable, Thereafter Total future minimum rental income Operating Leases, Future Minimum Payments Receivable Payables and Accruals [Abstract] Deferred rent Deferred Rent Credit, Noncurrent Deferred franchise and development fees Deferred Franchise And Development Fees Deferred Franchise And Development Fees Other Other Sundry Liabilities, Noncurrent Total noncurrent liabilities Other Liabilities, Noncurrent Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type Award Type [Axis] Equity Award Equity Award [Domain] Premium Options Premium Options [Member] Premium options. Performance Based Stock Options Performance Based Stock Options [Member] Performance based stock options. Time Based Stock Options Time Based Stock Options [Member] Time based stock options. Stock Options Employee Stock Option [Member] Restricted Shares Restricted Stock [Member] Performance Shares Performance Shares [Member] Exercise Price Range Exercise Price Range [Axis] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Exercise price equal to the fair market value of the common stock on the date of grant Exercise Price Two [Member] Exercise Price Two [Member] Directors Director [Member] Employees Employees [Member] Employees. Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Common stock, options outstanding (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Common stock, options vested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Common stock, options unvested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares Options to purchase common stock granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Option vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Stock-based compensation expense Share-based Compensation Options expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Aggregate intrinsic value of options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate intrinsic value of options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Authorized number of common stock for issuance (shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Number of share available for grant (shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted average grant date fair value (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Risk-free interest rates, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Risk-free interest rates, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Expected volatility, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Stock-based compensation expense Stock or Unit Option Plan Expense Accelerated vesting of awards (shares) Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number Incremental expense from plan modification Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost Unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized compensation expense, recognition period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options Debt Disclosure [Abstract] Senior Secured Revolving Credit Facility Short-term Debt, Type Short-term Debt, Type [Axis] Short-term Debt, Type Short-term Debt, Type [Domain] Letter of Credit Letter of Credit [Member] Swing Line Loans Swing Line Loans [Member] Swing line loans. 2014 Credit Agreement Credit Agreement Two Thousand Fourteen [Member] Credit agreement two thousand fourteen. Variable Rate Variable Rate [Axis] Variable Rate Variable Rate [Domain] Federal Funds Rate Federal Funds Effective Swap Rate [Member] LIBOR London Interbank Offered Rate (LIBOR) [Member] Base Rate Base Rate [Member] Sub limit of revolving facility Line of Credit Facility, Current Borrowing Capacity Debt instrument basis percentage Debt Instrument, Basis Spread on Variable Rate Debt instrument, interest rate Line of Credit Facility, Interest Rate During Period Letters of credit outstanding Letters of Credit Outstanding, Amount Revolving line of credit Long-term Line of Credit, Noncurrent Amount of borrowings available Line of Credit Facility, Remaining Borrowing Capacity Principal payments prior to maturity Debt Instrument, Periodic Payment, Principal Quarterly Financial Information Disclosure [Abstract] Schedule Of Quarterly Financial Information [Table] Schedule Of Quarterly Financial Information [Table] Schedule Of Quarterly Financial Information [Table] System-wide System Wide [Member] System Wide [Member] Schedule Of Quarterly Financial Information [Line Items] Schedule Of Quarterly Financial Information [Line Items] Schedule Of Quarterly Financial Information [Line Items] Selected Financial Data Selected Quarterly Financial Information [Abstract] Total revenue (Loss) income from operations Provision (benefit) for income taxes ($) Income Tax Expense (Benefit) Net (loss) income per share: Earnings Per Share [Abstract] Basic (usd per share) Earnings Per Share, Basic Diluted (usd per share) Earnings Per Share, Diluted Weighted average shares used in computing net (loss) income per share: Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Basic (shares) Weighted Average Number of Shares Outstanding, Basic Diluted (shares) Weighted Average Number of Shares Outstanding, Diluted Selected Operating Data Operating Data [Abstract] Operating data. Number of restaurants (at period end) Average unit volume (AUV) (usd per restaurant) Average Unit Volume Of Sales Average unit volume of sales. Comparable restaurant sales growth (%) Comparable Restaurant Sales Growth [Abstract] Comparable restaurant sales growth. Comparable restaurant sales growth (%) Sales Growth Percentage Increase Decrease Sales growth percentage increase decrease. Statement of Financial Position [Abstract] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts and other receivables, net Receivables, Net, Current Inventories Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property and equipment owned, net Property, Plant and Equipment, Net Property held under capital lease, net Capital Leases, Balance Sheet, Assets by Major Class, Net Goodwill Goodwill Trademarks, net Indefinite-Lived Trademarks Other intangible assets, net Other Intangible Assets, Net Deferred tax assets Deferred Income Tax Assets, Net Other assets Other Assets, Noncurrent Total assets Assets Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Current portion of obligations under capital leases Accounts payable Accounts Payable, Current Accrued salaries and vacation Employee-related Liabilities, Current Accrued insurance Accrued Insurance, Current Accrued income taxes payable Accrued Income Taxes, Current Accrued interest Interest Payable, Current Current portion of income tax receivable agreement payable Payable Under Tax Receivable Agreement Current Payable under tax receivable agreement current. Other accrued expenses and current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Revolver loan Line of Credit, Current Obligations under capital leases, net of current portion Other intangible liabilities, net Intangible Liabilities Noncurrent Intangible liabilities noncurrent. Income tax receivable agreement payable, net of current portion Payable Under Tax Receivable Agreement Noncurrent Payable under tax receivable agreement noncurrent. Other noncurrent liabilities Total liabilities Liabilities Commitments and contingencies (Note 13) Commitments and Contingencies Stockholders’ Equity Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.01 par value—100,000,000 shares authorized; none issued or outstanding Preferred Stock, Value, Issued Common stock, $0.01 par value—200,000,000 shares authorized; 39,009,451 and 38,661,850 shares issued and outstanding Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Preferred stock, par value (usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (shares) Preferred Stock, Shares Outstanding Common stock, par value (usd per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (shares) Common Stock, Shares Authorized Common stock, shares issued (shares) Common Stock, Shares, Issued Common stock, shares outstanding (shares) Common Stock, Shares, Outstanding Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Nonrecurring Fair Value, Measurements, Nonrecurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Impairment Losses Impairment of Long-Lived Assets Held-for-use Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Range Range Performance Obligation Type [Axis] Performance Obligation Type [Axis] Performance Obligation Type [Axis] Performance Obligation Type [Domain] Performance Obligation Type [Domain] [Domain] for Performance Obligation Type [Axis] Hardware Services Hardware Services [Member] Hardware Services [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Franchise license Franchise Rights [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Accumulated Deficit Retained Earnings [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Cumulative effect of adjustment resulted in an increase in accumulated deficit Cumulative Effect of New Accounting Principle in Period of Adoption Number of revenue streams Number Of Revenue Streams Number Of Revenue Streams Revenue allocated to loyalty points not redeemed Accrued Loyalty Rewards Program Liability, Current Accrued Loyalty Rewards Program Liability, Current Loyalty rewards program, expected loyalty points redemption period Loyalty Rewards Program, Expected Loyalty Points Redemption Period Loyalty Rewards Program, Expected Loyalty Points Redemption Period Franchise agreement term Finite-Lived Intangible Asset, Useful Life Franchise agreement renewal term Finite-Lived Intangible Asset, Useful Life Renewal Period Finite-Lived Intangible Asset, Useful Life Renewal Period Performance obligations expected to be satisfied, renewal term Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Unsatisfied performance obligations Revenue, Remaining Performance Obligation, Amount Total assets Total current liabilities Total liabilities Total stockholders' equity Total liabilities and stockholder’s equity Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Domestic Trademarks Schedule of Indefinite-Lived Intangible Assets [Table Text Block] Schedule of Intangible Assets Subject to Amortization Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Estimated Net Amortization Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Property Subject to or Available for Operating Lease, by Major Property Class [Table] Property Subject to or Available for Operating Lease, by Major Property Class [Table] Franchise, Rental Income Franchise, Rental Income [Member] Franchise, Rental Income [Member] Property Subject to or Available for Operating Lease [Line Items] Property Subject to or Available for Operating Lease [Line Items] Initial term of lease Lessee, Operating Lease, Term of Contract Sublease income, contingent rental income Operating Leases, Income Statement, Contingent Revenue Lessor, term of contract Lessor, Operating Lease, Term of Contract Summary of Estimated Useful Service Lives Property, Plant and Equipment [Table Text Block] Intangible Assets and Liabilities Remaining Useful Lives Finite-lived Intangible Assets Amortization Expense [Table Text Block] Summary of Non-Financial Instruments Measured at Fair Value on Nonrecurring Basis Fair Value Measurements, Nonrecurring [Table Text Block] Impact of New Accounting Pronouncements Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name Indefinite-lived Intangible Assets, Major Class Name [Domain] Trademarks Trademarks [Member] Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Cost Intangible Assets, Gross (Excluding Goodwill) Accumulated impairment charges Accumulated Impairment Losses Intangible Assets Accumulated Impairment Losses Intangible Assets Trademarks, net Intangible Assets, Net (Excluding Goodwill) Schedule of Costs and Related Accumulated Depreciation and Amortization of Major Classes of Property Change in Contract with Customer, Liability [Roll Forward] Change in Contract with Customer, Liability [Roll Forward] Change in Contract with Customer, Liability [Roll Forward] December 28, 2017 Contract with Customer, Liability Revenue recognized - beginning balance Contract with Customer, Liability, Revenue Recognized Additional contract liability Contract with Customer, Liability, New Contract Additions Contract with Customer, Liability, New Contract Additions Revenue recognized - additional contract liability Contract with Customer, Liability, New Contract Additions, Revenue Recognized Contract with Customer, Liability, New Contract Additions, Revenue Recognized September 26, 2018 Depreciation expense Depreciation Long-lived assets, non-cash impairment charges Asset Impairment Charges Schedule of Capital Leases Schedule of Capital Leased Assets [Table Text Block] Schedule of Operating Leases Lessee, Operating Lease, Disclosure [Table Text Block] Schedule of Net Rent Expense Schedule of Rent Expense [Table Text Block] Schedule of Minimum Future Rental Income Schedule of Property Subject to or Available for Operating Lease [Table Text Block] Income Tax Disclosure [Abstract] Federal Income Tax Note [Table] Federal Income Tax Note [Table] California CALIFORNIA Tax Credit Carryforward Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name Tax Credit Carryforward, Name [Domain] Enterprise Zone Enterprise Zone [Member] Enterprise zone. WOTC Work Opportunity Tax Credits [Member] Work opportunity tax credits. Income Tax Authority Income Tax Authority [Axis] Income Tax Authority Income Tax Authority [Domain] Federal Domestic Tax Authority [Member] State and Local Jurisdiction State and Local Jurisdiction [Member] Investments, Owned, Federal Income Tax Note [Line Items] Investments, Owned, Federal Income Tax Note [Line Items] Change in tax rate, decrease in deferred tax asset Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense (Benefit) Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense (Benefit) Change in tax rate, decrease in deferred tax liability Tax Cuts and Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Tax Cuts and Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Net benefit to deferred income tax expense Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Net Deferred Tax Asset (Liability), Provisional Income Tax Expense (Benefit) Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Net Deferred Tax Asset (Liability), Provisional Income Tax Expense (Benefit) Valuation allowance Deferred Tax Assets, Valuation Allowance Increase in valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Percentage of cash savings in taxes realized as a result of utilizing net operating losses payable to pre-IPO stockholders Percentage Of Operating Loss Carryforwards Tax Savings Payable To Pre Initial Public Offering Stockholders Percentage of operating loss carry forwards tax savings payable to pre initial public offering stockholders. TRA tax expense (benefit) Income Tax Expense (Benefit) Tax Receivable Agreement Income Tax Expense (Benefit) Tax Receivable Agreement Payments to pre-IPO stockholders under TRA Payment Related To Tax Receivable Agreement Payment related to tax receivable agreement. Deferred tax asset credit Deferred Tax Assets, Tax Credit Carryforwards Net operating loss carryforwards Operating Loss Carryforwards Tax credits carry forward Tax Credit Carryforward, Amount Alternative minimum tax credits Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax Unrecognized tax benefits Unrecognized Tax Benefits Unrecognized tax benefits interest accrued Unrecognized Tax Benefits, Interest on Income Taxes Accrued Unrecognized tax benefits penalties accrued Unrecognized Tax Benefits, Income Tax Penalties Accrued Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Unvested shares, beginning balance (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Released (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited, cancelled, or expired (shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period Unvested shares, ending balance (shares) Weighted-Average Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Unvested shares Weighted-Average Fair Value, beginning balance (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted, Weighted-Average Fair Value (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Released, Weighted-Average Fair Value (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited, cancelled, or expired, Weighted-Average Fair Value (usd per share) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures And Expired Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures And Expired Weighted Average Grant Date Fair Value Unvested shares Weighted-Average Fair Value, ending balance (usd per share) Schedule of Quarterly Financial Information Quarterly Financial Information [Table Text Block] Trademarks, Other Intangible Assets and Liabilities Intangible Assets Disclosure [Text Block] Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding-beginning balance (shares) Grants (shares) Exercised (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Forfeited, cancelled or expired (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding-ending balance (shares) Vested and expected to vest at end of period (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Exercisable at end of period (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted-Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Outstanding-beginning balance (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Grants (usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited, cancelled or expired (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding-ending balance (usd per share) Vested and expected to vest at end of period (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Exercisable at end of period (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted-average shares outstanding—Basic (shares) Dilutive effect of stock options and restricted shares (shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted-average shares outstanding—Diluted (shares) Schedule of Other Noncurrent Liabilities Other Noncurrent Liabilities [Table Text Block] Tax Cuts and Jobs Act of 2017, decrease in deferred tax liability Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax Benefit Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax Benefit TRA tax benefit Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Tax Receivable Agreement Expense (Benefit) Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Tax Receivable Agreement Expense (Benefit) Anti-dilutive securities not considered in diluted EPS calculation (shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Legal settlements Litigation Settlement, Expense Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] $ 4.09 Exercise Price Range One [Member] Exercise Price Range One [Member] $5.84 Exercise Price Range Two [Member] Exercise Price Range Two [Member] $9.65 - $13.95 Exercise Price Range Three [Member] Exercise Price Range Three [Member] $15.00 Exercise Price Range Four [Member] Exercise Price Range Four [Member] $4.09 - $15.00 Exercise Price Range Five [Member] Exercise Price Range Five [Member] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] Range of exercise prices (usd per share) Share Based Compensation Shares Authorized Under Stock Option Plans Options Exercise Price Share-based compensation, shares authorized under stock option plans, options exercise price. Range of exercise prices, minimum (usd per share) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit Range of exercise prices, maximum (usd per share) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit Number Outstanding (shares) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options Weighted-Average Remaining Contractual Life (in Years) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term Weighted-Average Exercise Price (usd per share) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price Number Exercisable (shares) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options Weighted-Average Exercise Price (usd per share) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Favorable Leasehold Interest Off-Market Favorable Lease [Member] Unfavorable Leasehold Interest Liability Above Market Leases [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Amortization expense Amortization Intangible asset subject to amortization, weighted average amortization period Finite-Lived Intangible Assets, Remaining Amortization Period Leases Leases of Lessee Disclosure [Text Block] Current income taxes: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Total current Current Income Tax Expense (Benefit) Deferred income taxes: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Total deferred Deferred Income Tax Expense (Benefit), Net of Revaluation Deferred Income Tax Expense (Benefit), Net of Revaluation Charge in lieu of tax (attributable to stock options) Income Tax Effects Allocated Directly to Equity, Employee Stock Options Adjustment to deferred taxes for tax rate change Tax provision for income taxes Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type Property, Plant and Equipment, Type [Domain] Buildings Building [Member] Land improvements Land Improvements [Member] Building improvements Building Improvements [Member] Restaurant equipment Restaurant Equipment [Member] Restaurant equipment. Other equipment Other Equipment [Member] Other equipment. Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Estimated useful service lives Property, Plant and Equipment, Useful Life Schedule of Other Accrued Expenses and Current Liabilities Other Current Liabilities [Table Text Block] Quarterly Results of Operations (Unaudited) Quarterly Financial Information [Text Block] Description of Business Nature of Operations [Text Block] Land Land [Member] Buildings and improvements Building and Building Improvements [Member] Other property and equipment Property, Plant and Equipment, Other Types [Member] Construction in progress Construction in Progress [Member] Property and equipment, gross Property, Plant and Equipment, Gross Less: accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Statutory federal income tax rate applied to earnings before income taxes and extraordinary items Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent TRA expense Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent Revaluation of deferred taxes Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent WOTC Credit Effective Income Tax Rate Reconciliation, Deductions, Working Opportunity Tax Credit Effective income tax rate reconciliation deductions working opportunity tax credit. State tax benefit (net of federal benefit) Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Stock option exercises Effective Income Tax Rate Reconciliation, Share-Based Compensation, Option Exercises Effective Income Tax Rate Reconciliation, Share-Based Compensation, Option Exercises Other Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Total Effective Income Tax Rate Reconciliation, Percent Unfavorable leasehold interest liability Favorable leasehold interest Finite-Lived Intangible Assets, Gross Less: accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Total favorable leasehold interest, net Finite-Lived Intangible Assets, Net Unfavorable leasehold interest liability Finite Lived Intangible Liabilities Gross Finite Lived Intangible Liabilities Gross Less: accumulated amortization Finite Lived Intangible Liabilities Accumulated Amortization Finite Lived Intangible Liabilities Accumulated Amortization Unfavorable leasehold interest liability, net Off-market Lease, Unfavorable Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Company-operated restaurant revenue Service [Member] Core and Non-core Status [Axis] Core and Non-core Status [Axis] Core and Non-core Status [Domain] Core and Non-core Status [Domain] Core Market Core [Member] Non-Core Market Non-core [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Income Taxes Income Tax Disclosure [Text Block] Related Party Transactions [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party Related Party [Axis] Related Party Related Party [Domain] Trimaran Pollo Partners, LLC Trimaran Pollo Partners L L C [Member] Information pertaining to Trimaran Pollo Partners, LLC. Related Party Transaction [Line Items] Related Party Transaction [Line Items] Company's outstanding common stock owned by Trimaran Pollo Partners, L.L.C. Outstanding membership interest, percentage Percentage Of Membership Interests Percentage of membership interests. Ownership percentage by stockholders Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners Liquidity Liquidity Policy [Policy Text Block] Liquidity Policy [Policy Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Concentration of Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Accounts and Other Receivables, Net Trade and Other Accounts Receivable, Policy [Policy Text Block] Inventories Inventory, Policy [Policy Text Block] Property and Equipment Owned, Net Property, Plant and Equipment, Policy [Policy Text Block] Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Goodwill and Indefinite-Lived Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Other Intangibles, Net-Definite Lived Intangible Assets, Finite-Lived, Policy [Policy Text Block] Deferred Financing Costs Deferred Charges, Policy [Policy Text Block] Insurance Reserves Insurance Reserve Policy [Policy Text Block] Insurance reserve. Restaurant and Franchise Revenue Revenue from Contract with Customer [Policy Text Block] Advertising Costs Advertising Costs, Policy [Policy Text Block] Preopening Costs Start-up Activities, Cost Policy [Policy Text Block] Operating Leases Revenue Recognition Leases, Operating [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Fair Value Measurements Fair Value Measurement, Policy [Policy Text Block] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Stock Based Compensation Compensation Related Costs, Policy [Policy Text Block] Earnings per Share Earnings Per Share, Policy [Policy Text Block] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Base rent Operating Leases, Rent Expense, Minimum Rentals Contingent rent Operating Leases, Rent Expense, Contingent Rentals Less: sublease income Operating Leases, Rent Expense, Sublease Rentals Net rent expense Operating Leases, Rent Expense, Net Income Statement [Abstract] Statement [Table] Statement [Table] Company-operated restaurant revenue Company-Operated Restaurant Revenue [Member] Company-Operated Restaurant Revenue [Member] Statement [Line Items] Statement [Line Items] Food and paper costs Cost, Direct Material Labor and related expenses Cost, Direct Labor Occupancy and other operating expenses Other Cost and Expense, Operating Gain on recovery of insurance proceeds, lost profits Gain On Business Interruption Insurance Recovery Lost Profit Gain on business interruption insurance recovery lost profit. Company restaurant expenses Company Restaurant Expenses Generally recurring costs associated with normal operations including cost of services. General and administrative expenses General and Administrative Expense Depreciation and amortization Depreciation, Depletion and Amortization Loss on disposal of assets Gain (Loss) on Disposition of Assets Expenses related to fire loss General Insurance Expense Gain on recovery of insurance proceeds, property, equipment and expenses Gain On Business Interruption Insurance Recovery Property Equipment And Expenses Gain on business interruption insurance recovery property equipment and expenses. Recovery of securities lawsuits related legal expenses Recovery of Securities Class Action Legal Costs Recovery of Securities Class Action Legal Costs Asset impairment and closed-store reserves Restructuring Costs and Asset Impairment Charges Total expenses Gain on disposition of restaurants Gain (Loss) on Disposition of Business (Loss) income from operations Interest expense—net of interest income of $12, $25, and $28 for the years ended December 26, 2018, December 27, 2017, and December 28, 2016, respectively Interest Income (Expense), Net Income tax receivable agreement (income) expense Tax Receivable Agreement (Income) Expenses Tax receivable agreement (income) expenses. (Loss) income before provision for income taxes (Benefit) provision for income taxes Net (loss) income Net (loss) income per share: Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Franchise Contract Franchise Contract [Member] Franchise Contract [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Operating Cash Flows, Direct Method [Abstract] Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustments to reconcile changes in net (loss) income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Stock-based compensation expense Impairment of property and equipment Closed-store reserves Restructuring Costs Amortization of deferred financing costs Amortization of Debt Issuance Costs Amortization of favorable and unfavorable leases, net Amortization of above and below Market Leases Excess income tax benefit related to share-based compensation plans Excess Tax Benefit from Share-based Compensation, Operating Activities Deferred income taxes, net Deferred Income Tax Expense (Benefit) Other Other Noncash Income (Expense) Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts and other receivables, net Increase (Decrease) in Accounts and Other Receivables Inventories Increase (Decrease) in Inventories Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Income taxes receivable/payable Increase (Decrease) in Income Taxes Other assets Increase (Decrease) in Other Operating Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued salaries and vacation Increase (Decrease) in Employee Related Liabilities Accrued insurance Increase (Decrease) in Insurance Liabilities Payment related to tax receivable agreement Other accrued expenses and liabilities Increase (Decrease) in Other Accrued Liabilities Restricted cash Increase (Decrease) in Restricted Cash Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Proceeds from disposition of restaurant Proceeds from Divestiture of Businesses Proceeds from fire insurance for property and equipment Fire Insurance Proceeds For Property And Equipment Fire insurance proceeds for property and equipment. Purchase of property and equipment Payments to Acquire Property, Plant, and Equipment Net cash flows used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Proceeds from borrowings on revolver and term loans Proceeds from Secured Lines of Credit Payments on revolver loan Repayments of Lines of Credit Minimum tax withholdings related to net share settlements Payments Related to Tax Withholding for Share-based Compensation Proceeds from issuance of common stock upon exercise of stock options, net of expenses Proceeds from Issuance of Common Stock Payment of obligations under capital leases Repayments of Long-term Capital Lease Obligations Deferred financing costs for revolver loan Payments of Financing Costs Excess income tax benefit related to share-based compensation plans Excess Tax Benefit from Share-based Compensation, Financing Activities Repurchases of common stock Payments for Repurchase of Common Stock Net cash flows used in financing activities Net Cash Provided by (Used in) Financing Activities Increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of year Cash and cash equivalents, end of year Supplemental cash flow information Supplemental Cash Flow Elements [Abstract] Cash paid for interest, net of capitalized interest Interest Paid, Excluding Capitalized Interest, Operating Activities Cash paid during the year for income taxes, net Income Taxes Paid, Net Non-cash investing and financing activity Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Unpaid purchases of property and equipment Capital Expenditures Incurred but Not yet Paid Borrowing on revolver for financing fees Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Deferred assets: Deferred Tax Assets, Net of Valuation Allowance [Abstract] Capital leases Deferred Tax Assets, Deferred Gain on Sale Leaseback Transaction Accrued vacation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Compensated Absences Accrued legal Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Legal Settlements Deferred rent Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Deferred Rent Accrued workers’ compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation Enterprise zone and other credits Net operating losses Deferred Tax Assets, Operating Loss Carryforwards Fixed assets Deferred Tax Assets, Property, Plant and Equipment Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Valuation allowance Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Deferred liabilities: Deferred Tax Liabilities, Gross [Abstract] Goodwill Deferred Tax Liabilities, Goodwill Trademark Deferred Tax Liabilities, Intangible Assets Prepaid expense Deferred Tax Liabilities, Prepaid Expenses Fixed asset Deferred Tax Liabilities, Property, Plant and Equipment Other Deferred Tax Liabilities, Other Deferred tax liabilities Deferred Tax Liabilities, Gross Net deferred tax asset Deferred Tax Assets, Net Current Credit Agreements Debt Disclosure [Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Schedule of Change in Franchise Contract Liability Balances Contract with Customer, Asset and Liability [Table Text Block] Schedule of Estimated Revenue to be Recognized Related to Performance Obligations Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Other Noncurrent Liabilities Other Liabilities Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance (shares) Shares, Outstanding Beginning balance Cumulative effect of accounting change (see Note 2) Stock based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Issuance of common stock related to restricted shares, net (shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Issuance of common stock related to restricted shares, net Stock Issued During Period, Value, Restricted Stock Award, Gross Issuance of common stock upon exercise of stock options (shares) Issuance of common stock upon exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Excess income tax benefit related to share-based compensation plans Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Shares repurchased for employee tax withholdings Shares Paid for Tax Withholding for Share Based Compensation Shares repurchased for employee tax withholdings (shares) Adjustments Related to Tax Withholding for Share-based Compensation Repurchase of common stock (shares) Repurchase of common stock Net income Ending balance (shares) Ending balance Other Accrued Expenses and Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] Concentration Risk Benchmark Concentration Risk Benchmark [Axis] Concentration Risk Benchmark Concentration Risk Benchmark [Domain] Revenue Sales Revenue, Net [Member] Concentration Risk Type Concentration Risk Type [Axis] Concentration Risk Type Concentration Risk Type [Domain] Geographic Concentration Risk Geographic Concentration Risk [Member] Greater Los Angeles area market Other markets Other than Los Angeles [Member] Other than Los Angeles [Member] Percentage of concentration Concentration Risk, Percentage Basis Of Presentation And Summary Of Significant Accounting Policies [Table] Basis Of Presentation And Summary Of Significant Accounting Policies [Table] Basis of presentation and summary of significant accounting policies table. Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Retained Earnings First Lien Credit Agreement First Lien Credit Agreement [Member] First lien credit agreement. Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Franchise Development Initial Option Agreement Franchise Development Initial Option Agreement [Member] Franchise development initial option agreement. Franchise Development Additional Option Agreement Franchise Development Additional Option Agreement [Member] Franchise development additional option agreement. Franchise Development Agreement Franchise Development Agreement [Member] Franchise development agreement. Texas TEXAS Supplier Supplier [Axis] Share-based Goods and Nonemployee Services Transaction, Supplier Share-based Goods and Nonemployee Services Transaction, Supplier [Domain] Supplier One Supplier One [Member] Supplier one. Supplier Two Supplier Two [Member] Supplier two. Largest Supplier One Largest Supplier One [Member] Largest supplier one. Purchased Purchased [Member] Purchased. Accounts Payable Accounts Payable [Member] Accounts Receivable Accounts Receivable [Member] Supplier Concentration Risk Supplier Concentration Risk [Member] Balance Sheet Location Balance Sheet Location [Axis] Balance Sheet Location Balance Sheet Location [Domain] Other Assets Other Assets [Member] Income Statement Location Income Statement Location [Axis] Income Statement Location Income Statement Location [Domain] Interest Expense Interest Expense [Member] General and Administrative Expense General and Administrative Expense [Member] Limited Liability Company Limited Liability Company [Member] Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] Basis of presentation and summary of significant accounting policies. Total amount of outstanding debt Long-term Debt and Capital Lease Obligations Cash available Number of restaurants closed Number Of Restaurant Closed Number of restaurant closed. Prepayment for long-term line of credit Repayments of Long-term Lines of Credit Abandoned site and other site selection costs Abandoned Site and Other Site Selection Costs Abandoned Site and Other Site Selection Costs Capitalized internal cost Capitalized Internal Wages Capitalized internal wages. Capitalized internal interest cost Capitalized Interest Costs, Including Allowance for Funds Used During Construction Asset impairment charges Transaction costs Debt Refinancing Costs Debt refinancing costs. Deferred financing fees net of accumulated amortization Debt Issuance Costs, Net Amortization expense for deferred financing costs Expense for payroll and benefits reserves Labor and Related Expense Promotional allowances amount Promotional Allowances For Restaurant And Franchise Revenue Promotional Allowances For Restaurant And Franchise Revenue Advertising expense Advertising Expense Advertising fees Advertising Fee From Affiliates Advertising fee from affiliates. Percentage of monthly franchise fee Franchise Fee Percentage Franchise fee percentage. Accrued advertising Accrued Advertising Advertising cost included in accounts receivable and current assets Advertising Costs Included In Accounts Receivable And Current Assets Advertising costs included in accounts receivable and current assets. Preopening costs Pre-Opening Costs Number of restaurants damaged by fire Number Of Restaurants Damaged By Fire Number of restaurants damaged by fire. Expenses related to fire loss General Insurance Expense, Fire Loss General Insurance Expense, Fire Loss Disposition of assets related to fire Disposal Group, Including Discontinued Operation, Assets Gain on recovery of insurance proceeds, related to the reimbursement of property and equipment and expenses incurred Gain Loss On Business Interruption Insurance Recovery Gain (loss) on business interruption insurance recovery. Gain on recovery of insurance proceeds, related to the reimbursement of lost profits Amount received from insurance company in cash Proceeds from Insurance Premiums Collected Recovery of securities lawsuits related legal expenses Unrecognized tax benefits, accrual of interest or penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Unrecognized tax benefits, interest or penalties expenses Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Charge relating to present value of total expected TRA payments Tax Receivable Agreement Expected Payments Tax receivable agreement expected payments. Impairment of assets Number of restaurants that failed impairment testing Number of Restaurants That Failed Impairment Testing Number of Restaurants That Failed Impairment Testing Cumulative effect of adjustment resulted in an increase in accumulated deficit Cumulative effect adjustment as percentage of total assets Cumulative Effect Adjustment, Percentage Of Total Assets Cumulative Effect Adjustment, Percentage Of Total Assets Number of commitments to open franchised restaurants Number of Commitments to Open Franchised Restaurants Number of Commitments to Open Franchised Restaurants Number of years available under plan Term Available Under Plan To Develop And Open Restaurants Term available under plan to develop and open restaurants. Related party agreement, termination period Agreement Termination Period Agreement termination period. Operating lease obligations Changes in Stock Options Share-based Compensation, Stock Options, Activity [Table Text Block] Stock Options By Range of Exercise Prices Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] Schedule of Changes in Restricted Shares Nonvested Restricted Stock Shares Activity [Table Text Block] Computation of Basic and Diluted Net Income per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Reconciliation of Basic and Diluted Share Counts Schedule of Weighted Average Number of Shares [Table Text Block] Related Party Transactions Related Party Transactions Disclosure [Text Block] Schedule of Provision for Income Taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Numerator: Net Income (Loss) Attributable to Parent [Abstract] Denominator: Weighted-average shares outstanding—Diluted (shares) Net (loss) income per share—Basic (usd per share) Net (loss) income per share—Diluted (usd per share) Unfavorable Leasehold Interest Favorable Leasehold Interest Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] December 25, 2019 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months December 30, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two December 29, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three December 28, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four December 28, 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Unfavorable Leasehold Interest Finite-Lived Intangible Liabilities, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Finite-Lived Intangible Liabilities, Net, Amortization Expense, Fiscal Year Maturity [Abstract] December 25, 2019 Finite Lived Intangible Liabilities Amortization Expenses Next Twelve Months Finite Lived Intangible Liabilities Amortization Expenses Next Twelve Months December 30, 2020 Finite Lived Intangible Liabilities Amortization Expenses Year Two Finite Lived Intangible Liabilities Amortization Expenses Year Two December 29, 2021 Finite Lived Intangible Liabilities Amortization Expenses Year Three Finite Lived Intangible Liabilities Amortization Expenses Year Three December 28, 2022 Finite Lived Intangible Liabilities Amortization Expenses Year Four Finite Lived Intangible Liabilities Amortization Expenses Year Four December 28, 2023 Finite Lived Intangible Liabilities Amortization Expenses Year Five Finite Lived Intangible Liabilities Amortization Expenses Year Five Thereafter Finite Lived Intangible Liabilities Amortization Expenses After Year Five Finite Lived Intangible Liabilities Amortization Expenses After Year Five Accrued sales and property taxes Taxes Payable, Current Accrued legal settlements and professional fees Accrued Legal Settlements And Professional Fees Accrued Legal Settlements And Professional Fees Gift card liability Gift Card Liability, Current Other Other Accrued Liabilities, Current Total other accrued expenses and current liabilities Interest income Investment Income, Interest Earnings Per Share Earnings Per Share [Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Employee Benefit Plans Compensation and Employee Benefit Plans [Text Block] Stock-Based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block]