Change In Contract With Customer, Liability [Roll Forward]

No definition available.

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- Definition

Contract with Customer, Liability, New Contract Additions

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized that was previously included in balance and additional obligation deferred to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

No definition available.

+ Details

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-2

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

+ Details

Name:	us-gaap_ContractWithCustomerLiabilityCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

+ Details

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- Details

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- Details

Name:	srt_ProductOrServiceAxis=loco_LoyaltyRewardProgramMember
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- Details

Name:	us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis=2025-06-26
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REVENUE FROM CONTRACTS WITH CUSTOMERS - Loyalty Reward Liability and Gift Card Liability (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2025	Sep. 25, 2024	Sep. 24, 2025	Sep. 25, 2024	Dec. 25, 2024
Change in Contract with Customer, Liability [Roll Forward]
Gift card liability	$ 4,821		$ 4,821		$ 5,100
Gift card liability
Change in Contract with Customer, Liability [Roll Forward]
Gift card liability	4,821		4,821		$ 5,100
Revenue recognized from gift card liability balance at the beginning of the year	205	$ 214	848	$ 833
Loyalty reward program
Change in Contract with Customer, Liability [Roll Forward]
Loyalty rewards liability, beginning balance			844	687
Revenue deferred			1,920	1,620
Revenue recognized			(1,700)	(1,506)
Loyalty rewards liability, ending balance	$ 1,064	$ 801	$ 1,064	$ 801
Loyalty reward program \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-06-26
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year