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.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Represents the number of restaurants.

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The cash inflow associated with the amount received from entity's first offering of stock to the public.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Organization and Description of Business - Additional Information (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) Restaurants	Dec. 31, 2024 Restaurants	Feb. 18, 2024	Apr. 01, 2016
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of restaurants \| Restaurants		37	43
Proceeds from the issuance of class A common stock		$ 46,167
Austin, Texas
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Lease term			10 years
Class A Common Stock \| IPO
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Stock issued price per share \| $ / shares	$ 12
Number of shares issued \| shares	4,140,000
Proceeds from the issuance of class A common stock	$ 46,200
GEN LLC
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Subsidiary, Ownership Percentage, Parent			14.00%
GEN LLC \| GKBH Restaurant, LLC [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Subsidiary, Ownership Percentage, Parent					50.00%
GEN Hawaii, LLC [Member] \| GKBH Restaurant, LLC [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Remaining equity investment ownership percentage				50.00%
Subsidiary, Ownership Percentage, Parent				100.00%
Maximum [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Lease term			25 years
Minimum [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Lease term			20 years