BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Gain on Recovery of Insurance Proceeds (Details) $ in Thousands	3 Months Ended
Mar. 27, 2024 USD ($)
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Gain on Recovery of Insurance Proceeds For Property And Equipment	$ 41
Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Gain on Recovery of Insurance Proceeds For Property And Equipment	$ 100

The net gain from insurance settlement for property and equipment that exceeds incremental costs incurred from the event causing an interruption of business, plus the insurance award for earnings lost from the event, such as a natural catastrophe, explosion or fire.

No definition available.

Name:	loco_GainOnRecoveryOfInsuranceProceedsForPropertyAndEquipment
Namespace Prefix:	loco_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration