Property, Plant and Equipment [Abstract] Schedule Of Property Plant And Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type Long-Lived Tangible Asset [Axis] Property, Plant and Equipment, Type Long-Lived Tangible Asset [Domain] 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 Plant And Equipment [Line Items] Property, Plant and Equipment [Line Items] 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 Property, Plant and Equipment, Net Accounting Policies [Abstract] 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. Number of Restaurants Remain Closed [Axis] Number of Restaurants Remain Closed [Axis] Number of Restaurants Remain Closed [Axis] Number of Restaurants Remain Closed [Domain] Number of Restaurants Remain Closed [Domain] [Domain] for Number of Restaurants Remain Closed [Axis] Number of Restaurants Reopened [Domain] Number of Restaurants Reopened [Domain] [Domain] for Number of Restaurants Reopened [Axis] Number of Restaurants Reopened [Axis] Number of Restaurants Reopened [Axis] Number of Restaurants Reopened [Axis] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Franchisor Disclosure Franchisor Disclosure [Axis] Franchisor Disclosure Franchisor Disclosure [Domain] Entity Operated Units Entity Operated Units [Member] Franchised Units Franchised Units [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] closed store [Member] closed store [Member] closed store [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Los Angeles Los Angeles [Member] Information pertaining to Los Angeles. TEXAS TEXAS ARIZONA ARIZONA CALIFORNIA CALIFORNIA Debt Instrument Debt Instrument [Axis] Debt Instrument, Name Debt Instrument, Name [Domain] Credit Agreement Two Thousand Eighteen Credit Agreement Two Thousand Eighteen [Member] Credit Agreement Two Thousand Eighteen [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] Fair Value, Inputs, Level 1 Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Nonrecurring Fair Value, Nonrecurring [Member] Fair Value, Recurring [Member] Fair Value, Recurring [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Concentration Risk Type Concentration Risk Type [Axis] Concentration Risk Type Concentration Risk Type [Domain] Supplier Concentration Risk Supplier Concentration Risk [Member] Geographic Concentration Risk Geographic Concentration Risk [Member] Supplier [Axis] Supplier [Axis] Supplier [Domain] Supplier [Domain] Supplier One Supplier One [Member] Supplier one. Largest Supplier One Largest Supplier One [Member] Largest supplier one. Concentration Risk Benchmark Concentration Risk Benchmark [Axis] Concentration Risk Benchmark Concentration Risk Benchmark [Domain] Accounts Payable Accounts Payable [Member] Purchased Purchased [Member] Purchased. Revenue Revenue Benchmark [Member] Asset Class Asset Class [Axis] Asset Class Asset Class [Domain] Indefinite-lived Intangible Assets Indefinite-lived Intangible Assets [Member] Property, Plant and Equipment, Other Types [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. Number of Restaurants Remain Closed Number of Restaurants Remain Closed Number of Restaurants Remain Closed Number of Restaurants Temporary Closed Number of Restaurants Temporary Closed Number of Restaurants Temporary Closed Number of Restaurants Reopened Number of Restaurants Reopened Number of Restaurants Reopened Letters of Credit Outstanding, Amount Letters of Credit Outstanding, Amount Repayments of Lines of Credit Repayments of Lines of Credit Derivative Liability, Fair Value, Gross Liability Derivative Liability, Fair Value, Gross Liability Property and equipment owned, net Depreciation Depreciation Number of operating segments Number of Operating Segments Number of Restaurants Number of Restaurants Treasury Stock, Value, Acquired, Cost Method Treasury Stock, Value, Acquired, Cost Method Total amount of outstanding debt Long-term Debt Cash available Cash and Cash Equivalents, at Carrying Value Assets Held-for-sale, Not Part of Disposal Group, Current Assets Held-for-sale, Not Part of Disposal Group, Current Proceeds from Long-term Lines of Credit Proceeds from Long-term Lines of Credit Number of suppliers Number Of Suppliers Number of suppliers. Percentage of concentration Concentration Risk, Percentage Asset Impairment Charges Asset Impairment Charges Right-of-Use Assets, Net Right-of-Use Assets, Net Right-of-Use Assets, Net Derivative Asset, Fair Value, Gross Asset Derivative Asset, Fair Value, Gross Asset Number of restaurants closed Number of Restaurants Closed Number of Restaurants Closed Operating Lease, Expense Operating Lease, Expense 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 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. Income tax receivable agreement (income) expense Tax Receivable Agreement (Income) Expenses Tax receivable agreement (income) expenses. Stock Repurchase Program, Authorized Amount Stock Repurchase Program, Authorized Amount Impairment of Long-Lived Assets to be Disposed of Impairment of Long-Lived Assets Held-for-use Impairment of Right-of-Use Assets Impairment of Right-of-Use Assets Impairment of Right-of-Use Assets Other Liabilities, Noncurrent [Abstract] Schedule of Other Noncurrent Liabilities Other Noncurrent Liabilities [Table Text Block] Earnings Per Share [Abstract] Weighted-average shares outstanding—basic (shares) Weighted Average Number of Shares Outstanding, Basic 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) Weighted Average Number of Shares Outstanding, Diluted Leases [Abstract] Lease, Cost [Table Text Block] Lease, Cost [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Finance Lease, Liability, Fiscal Year Maturity [Table Text Block] Finance Lease, Liability, Fiscal Year Maturity [Table Text Block] Leases of Lessee Disclosure [Text Block] Leases of Lessee Disclosure [Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Other than Los Angeles Other than Los Angeles [Member] Other than Los Angeles [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] 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] Liquidity Liquidity Policy [Policy Text Block] Liquidity Policy [Policy Text Block] Concentration of Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Goodwill and Indefinite Lived Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Fair Value Measurement Fair Value Measurement, Policy [Policy Text Block] Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Closed-Store Reserves Costs Associated with Exit or Disposal Activity or Restructuring [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Recent Accounting Pronouncements Adopted and Not Yet Adopted and Changes in Accounting Policies New Accounting Pronouncements, Policy [Policy Text Block] Other Noncurrent Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Noncurrent [Text Block] Income Statement [Abstract] Statement [Table] Statement [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Company-operated restaurant revenue Service [Member] Franchise revenue Franchise [Member] Franchise advertising fee revenue Franchise Advertising Fee [Member] Franchise Advertising Fee [Member] Statement [Line Items] Statement [Line Items] Revenue Revenues [Abstract] Total revenue Revenue from Contract with Customer, Including Assessed Tax Cost of operations Cost of Goods and Services Sold [Abstract] Food and paper cost Cost, Direct Material Labor and related expenses Cost, Direct Labor Occupancy and other operating expenses Other Cost and Expense, Operating 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 Franchise expenses Franchisor Costs Depreciation and amortization Depreciation, Depletion and Amortization Loss on disposal of assets Gain (Loss) on Disposition of Assets Impairment and closed-store reserves Restructuring Costs and Asset Impairment Charges Impairment of Long-Lived Assets to be Disposed of Impairment of Long-Lived Assets to be Disposed of Total expenses Costs and Expenses Income from operations Operating Income (Loss) Interest expense, net Interest Expense Income before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net income Net Income (Loss) Attributable to Parent Net income per share Basic (usd per share) Earnings Per Share, Basic Diluted (usd per share) Earnings Per Share, Diluted Weighted-average shares used in computing net income per share Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Basic (shares) Diluted (shares) Debt Disclosure [Abstract] Debt Instrument [Table] Schedule of Long-term Debt Instruments [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Instrument [Domain] Derivative Instrument [Domain] Derivative Instrument [Domain] Interest Rate Swap [Member] Interest Rate Swap [Member] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Eliott Olvera, et al v. El Pollo Loco, Inc., et al [Member] Eliott Olvera, et al v. El Pollo Loco, Inc., et al [Member] Eliott Olvera, et al v. El Pollo Loco, Inc., et al [Member] Fair Value, Nonrecurring [Member] Credit Facility Credit Facility [Axis] Credit Facility Credit Facility [Domain] Senior Secured Revolving Credit Facility Revolving Credit Facility [Member] Debt Instrument [Axis] Debt Instrument, Name [Domain] 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. Variable Rate Variable Rate [Axis] Variable Rate Variable Rate [Domain] Federal Funds Rate Fed Funds Effective Rate Overnight Index Swap Rate [Member] LIBOR London Interbank Offered Rate (LIBOR) [Member] Base Rate Base Rate [Member] Range Statistical Measurement [Axis] Range Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Derivative Asset, Notional Amount Derivative Asset, Notional Amount Derivative, Fixed Interest Rate Derivative, Fixed Interest Rate Derivative, Variable Interest Rate Derivative, Variable Interest Rate Interest Expense, Debt Interest Expense, Debt Interest Income, Other Interest Income, Other Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion Senior secured revolving facility Line of Credit Facility, Maximum Borrowing Capacity Senior secured revolving facility term Debt Instrument, Term Sub limit of revolving facility Line of Credit Facility, Current Borrowing Capacity Revolving credit facility maturity period Debt Instrument, Maturity Date 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 Revolver loan Long-term Line of Credit, Noncurrent Amount of borrowings available Line of Credit Facility, Remaining Borrowing Capacity Proceeds from (Repayments of) Lines of Credit Proceeds from (Repayments of) Lines of Credit Principal payments prior to maturity Debt Instrument, Periodic Payment, Principal Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax Interest Income (Expense), Net Interest Income (Expense), Net Payables and Accruals [Abstract] Other Accrued Expenses and Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] 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 25, 2019 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 43915 Derivative Instruments and Hedging Activities Disclosure [Abstract] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block] Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block] Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Statement of Financial Position [Abstract] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Accounts and other receivables, net Receivables, Net, Current Inventories Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Income Taxes Receivable, Current Income Taxes Receivable, Current Total current assets Assets, Current Property held under operating leases, net (ROU asset) Operating Lease, Right-of-Use Asset Goodwill Goodwill Trademarks Indefinite-Lived Trademarks 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 finance leases Capital Lease Obligations, Current Current portion of obligations under operating leases Operating Lease, Liability, Current Accounts payable Accounts Payable, Current Accrued salaries and vacation Employee-related Liabilities, Current Accrued insurance Accrued Insurance, 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 Obligations under finance leases, net of current portion Capital Lease Obligations, Noncurrent Operating Lease, Liability, Noncurrent Operating Lease, Liability, Noncurrent Deferred Income Tax Liabilities, Net Deferred Income Tax Liabilities, Net Income tax receivable agreement payable, net of current portion Payable Under Tax Receivable Agreement Noncurrent Payable under tax receivable agreement noncurrent. Other noncurrent liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies 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; 35,089,983 and 35,126,582 shares issued and outstanding Common Stock, Value, Issued Additional paid-in-capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders' equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders' equity Liabilities and Equity Accrued sales and property taxes Taxes Payable, Current Contract with Customer, Liability, Current Contract with Customer, Liability, Current Accrued legal settlements and professional fees Accrued Professional Fees Deferred Franchise and Development Fees, Current Deferred Franchise and Development Fees, Current Deferred Franchise and Development Fees, Current Other Other Accrued Liabilities, Current Total other accrued expenses and current liabilities Share-based Payment Arrangement [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 Award Type [Domain] Premium Options Premium Options [Member] Premium options. Employee Stock Option Share-based Payment Arrangement, Option [Member] Restricted Stock Restricted Stock [Member] Performance Shares Performance Shares [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] 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 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Unrecognized compensation expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Unrecognized compensation expense, period for recognition Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Unvested restricted shares outstanding (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value 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 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 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 Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures And Expired Weighted Average Grant Date Fair Value Unrecognized compensation expense Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Stock-based compensation Share-based Payment Arrangement, Noncash Expense Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Long-Lived Tangible Asset [Axis] Long-Lived Tangible Asset [Domain] Property lease modification [Member] Property lease modification [Member] Property lease modification [Member] Property Lease [Member] Property Lease [Member] Property Lease [Member] Equipment Lease [Member] Equipment Lease [Member] Equipment Lease [Member] Lease Not Yet Commenced [Member] Lease Not Yet Commenced [Member] Lease Not Yet Commenced [Member] Statistical Measurement [Axis] Statistical Measurement [Domain] Minimum [Member] Maximum [Member] Accounting Standards Update [Axis] Accounting Standards Update [Axis] Accounting Standards Update [Domain] Accounting Standards Update [Domain] Accounting Standards Update 2016-02 [Member] Accounting Standards Update 2016-02 [Member] Operating Expense [Member] Operating Expense [Member] General and Administrative Expense [Member] General and Administrative Expense [Member] Interest Expense [Member] Interest Expense [Member] Restructuring Charges [Member] Restructuring Charges [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Lessor, Operating Lease, Term of Contract Lessor, Operating Lease, Term of Contract Finance Lease, Liability, to be Paid, Remainder of Fiscal Year Finance Lease, Liability, to be Paid, Remainder of Fiscal Year Capital Leases, Future Minimum Payments Due, Next Twelve Months Capital Leases, Future Minimum Payments Due, Next Twelve Months Operating Lease, Payments Operating Lease, Payments Operating Lease, Cost Operating Lease, Cost Short-term Lease, Cost Short-term Lease, Cost Variable Lease, Cost Variable Lease, Cost Sublease Income Sublease Income Lease, Cost Lease, Cost Operating Lease, Liability Operating Lease, Liability Finance Lease, Principal Payments Finance Lease, Principal Payments Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Finance Lease, Weighted Average Remaining Lease Term Finance Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Discount Rate, Percent Operating Lease, Weighted Average Discount Rate, Percent Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Remaining Lease Term Finance Lease, Weighted Average Discount Rate, Percent Finance Lease, Weighted Average Discount Rate, Percent Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments Due, Next Twelve Months 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 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months Finance Lease, Liability, to be Paid, Year Two Finance Lease, Liability, to be Paid, Year Two Capital Leases, Future Minimum Payments Due in Two Years Capital Leases, Future Minimum Payments Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years 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 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Two Years Finance Lease, Liability, to be Paid, Year Three Finance Lease, Liability, to be Paid, Year Three Capital Leases, Future Minimum Payments Due in Three Years Capital Leases, Future Minimum Payments Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years 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 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Three Years Finance Lease, Liability, to be Paid, Year Four Finance Lease, Liability, to be Paid, Year Four Capital Leases, Future Minimum Payments Due in Four Years Capital Leases, Future Minimum Payments Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years 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 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Four Years Finance Lease, Liability, to be Paid, Year Five Finance Lease, Liability, to be Paid, Year Five Capital Leases, Future Minimum Payments Due in Five Years Capital Leases, Future Minimum Payments Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years 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 Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Five Years Finance Lease, Liability, to be Paid, after Year Five Finance Lease, Liability, to be Paid, after Year Five Capital Leases, Future Minimum Payments Due Thereafter Capital Leases, Future Minimum Payments Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter Finance Lease, Liability, Payment, Due Finance Lease, Liability, Payment, Due Capital Leases, Future Minimum Payments Due Capital Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals Finance Lease, Liability, Undiscounted Excess Amount Finance Lease, Liability, Undiscounted Excess Amount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Finance Lease, Liability Finance Lease, Liability Capital Leases, Future Minimum Payments, Interest Included in Payments Capital Leases, Future Minimum Payments, Interest Included in Payments Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments Capital Lease Obligations, Current Finance Lease, Liability, Current Finance Lease, Liability, Current Current portion of obligations under operating leases Finance Lease, Liability, Noncurrent Finance Lease, Liability, Noncurrent Finance Lease, Interest Expense Finance Lease, Interest Expense Number Of Leases Number Of Leases Number of leases. Number Of Finance Leases Number Of Finance Leases Number Of Finance Leases Number of Restaurants with lease modification Number of Restaurants with lease modification Number of Restaurants with lease modification Operating Lease, Lease Income Operating Lease, Lease Income Operating Lease, Impairment Loss Operating Lease, Impairment Loss Capital Leases of Lessee, Contingent Rentals, Basis Spread on Variable Rate Capital Leases of Lessee, Contingent Rentals, Basis Spread on Variable Rate Numerator: Net Income (Loss) Attributable to Parent [Abstract] Net income Denominator: Weighted-average shares outstanding—diluted (shares) Net income (loss) per share—basic (usd per share) Net income (loss) per share—diluted (usd per share) Anti-dilutive securities not considered in diluted EPS calculation (shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Schedule of Costs and Related Accumulated Depreciation and Amortization of Major Classes of Property and Equipment Property, Plant and Equipment [Table Text Block] Stock-based compensation [Abstract] Stock-based compensation [Abstract] Share-based Payment Arrangement, Option, Activity [Table Text Block] Share-based Payment Arrangement, Option, Activity [Table Text Block] Nonvested Restricted Stock Shares Activity [Table Text Block] Nonvested Restricted Stock Shares Activity [Table Text Block] Revenue from Contracts with Customers Revenue from Contract with Customer [Text Block] Fair Value, Assets Measured on Recurring Basis [Table Text Block] Fair Value, Assets Measured on Recurring Basis [Table Text Block] Non-Financial Instruments Measured at Fair Value on a Nonrecurring Basis Fair Value Measurements, Nonrecurring [Table Text Block] 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] Property and Equipment Property, Plant and Equipment Disclosure [Text Block] Commitments and Contingencies Disclosure [Abstract] Other Commitments [Table] Other Commitments [Table] 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] Daniel Turocy, et al. and Ron Huston et al v. El Pollo Loco Holdings, Inc., et al [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] 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 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 Title of Individual [Domain] Officers Officer [Member] Other Commitments [Line Items] Other Commitments [Line Items] Date of class action filed in court Loss Contingency, Lawsuit Filing Date Number of lawsuits consolidated Number Of Lawsuits Number of lawsuits. Value of damages awarded Loss Contingency, Damages Awarded, Value Accrual associated with loss contingencies Loss Contingency Accrual Purchase commitments, estimated obligations Purchase Obligation Number of leases assigned to franchisees Latest lease expiration year Lease Expiration Year Lease expiration year. 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. Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Impaired Long-Lived Assets Held and Used, Asset Name [Domain] Impaired Long-Lived Assets Held and Used, Asset Name [Domain] Property, Plant and Equipment [Line Items] Number of Restaurants Schedule Of Related Party Transactions By Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Ownership [Axis] Ownership [Axis] Ownership [Domain] Ownership [Domain] Noncontrolling Interest [Member] Noncontrolling Interest [Member] 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. Equity Method Investment, Ownership Percentage Outstanding membership interest percentage, at least Percentage Of Membership Interests Percentage of membership interests. Ownership percentage by stockholders Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners Net Income (Loss) Per Share Earnings Per Share [Text Block] Statement of Other Comprehensive Income [Abstract] Net income Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Other Comprehensive Income (Loss), Net of Tax Other Comprehensive Income (Loss), Net of Tax Stock-Based Compensation Share-based Payment Arrangement [Text Block] 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 Credit Agreements Debt Disclosure [Text Block] Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] 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] Retained Earnings Retained Earnings [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Loyalty Rewards Program, Points Needed For One Reward Loyalty Rewards Program, Points Needed For One Reward Loyalty Rewards Program, Points Needed For One Reward Loyalty Rewards Program, Award Earned Loyalty Rewards Program, Award Earned Loyalty Rewards Program, Award Earned Loyalty Rewards Program, Expiration Period For Inactivity Loyalty Rewards Program, Expiration Period For Inactivity Loyalty Rewards Program, Expiration Period For Inactivity 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 (in years) Loyalty Rewards Program, Expected Loyalty Points Redemption Period Loyalty Rewards Program, Expected Loyalty Points Redemption Period Franchise agreement term (in years) Finite-Lived Intangible Asset, Useful Life Franchise agreement renewal term (in years) Finite-Lived Intangible Asset, Useful Life Renewal Period Finite-Lived Intangible Asset, Useful Life Renewal Period Satisfied over renewal term (in years) Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Unsatisfied performance obligations Revenue, Remaining Performance Obligation, Amount Computation of Basic and Diluted Net Income (Loss) 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] Class of Treasury Stock [Table] Class of Treasury Stock [Table] 2018 Stock Repurchase Plan [Member] 2018 Stock Repurchase Plan [Member] 2018 Stock Repurchase Plan [Member] 2019 Stock Repurchase Plan [Member] 2019 Stock Repurchase Plan [Member] 2019 Stock Repurchase Plan [Member] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) [Abstract] Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) [Abstract] Other Comprehensive Income (Loss) [Member] Other Comprehensive Income (Loss) [Member] Accumulated Deficit Shares, Outstanding Shares, Outstanding Stockholders' Equity Attributable to Parent Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Share-based Payment Arrangement, Decrease for Tax Withholding Obligation Share-based Payment Arrangement, Decrease for Tax Withholding Obligation Treasury Stock, Value, Acquired, Cost Method Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Schedule of Other Accrued Expenses and Current Liabilities Other Current Liabilities [Table Text Block] Deferred franchise and development fees Contract with Customer, noncurrent Contract with Customer, noncurrent Derivative Liability Derivative Liability Other Other Sundry Liabilities, Noncurrent Total other noncurrent liabilities Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash flows (used in) provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Stock-based compensation expense Impairment of Long-Lived Assets to be Disposed of Loss on disposal of assets Impairment of property and equipment Amortization of deferred financing costs Amortization of Debt Issuance Costs Amortization of favorable and unfavorable leases, net Amortization of above and below Market Leases Deferred income taxes, net Deferred Income Tax Expense (Benefit) 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 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 Income taxes payable Increase (Decrease) in Income Taxes Other accrued expenses and liabilities Increase (Decrease) in Other Accrued Liabilities Net cash flows (used in) 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 [Abstract] 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 [Abstract] Payments on revolver and swingline loan Payment of obligations under finance leases Repayments of Long-term Capital Lease Obligations Payments for Repurchase of Common Stock Payments for Repurchase of Common Stock Net cash flows provided by (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 period Cash and cash equivalents, end of period Supplemental cash flow information Supplemental Cash Flow Information [Abstract] Cash paid during the period for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Unpaid purchases of property and equipment Capital Expenditures Incurred but Not yet Paid Stock Repurchase Accrued not Paid Stock Repurchase Accrued not Paid Stock Repurchase Accrued not Paid Schedule of Non-cash Transactions Noncash Investing and Financing Items [Abstract] 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 Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Emerging Growth Company Entity Emerging Growth Company Small Business Entity Entity Small Business Entity Current Reporting Status Entity Current Reporting Status Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Schedule of Change in Franchise Contract Liability Balances Contract with Customer, Contract Asset, Contract Liability, and Receivable [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] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Franchise Contract Franchise Contract [Member] Franchise Contract [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period