Related Party Transactions (Details) $ in Thousands	3 Months Ended		9 Months Ended
Related Party Transactions (Details) $ in Thousands	Sep. 27, 2025 USD ($) store warehouse	Sep. 28, 2024 USD ($) store warehouse	Sep. 27, 2025 USD ($) store warehouse	Sep. 28, 2024 USD ($) store warehouse	Dec. 28, 2024 USD ($)
Related Party Transaction [Line Items]
Number of stores \| store	563		563
Operating lease, right-of-use asset	$ 1,123,785		$ 1,123,785		$ 1,014,678
Accounts and financing receivable, before allowance for credit loss	$ 82,284		$ 82,284		70,971
Related Party
Related Party Transaction [Line Items]
Number of stores \| store	14	14	14	14
Number of warehouses \| warehouse	1	1	1	1
Operating lease, right-of-use asset	$ 45,700		$ 45,700		38,700
Operating lease liability	50,800		50,800		$ 43,800
Aggregate annual lease payments	$ 1,900	$ 1,900	$ 5,700	$ 5,500

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Grocery Outlet Holding Corp. 10-Q