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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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Represents the number of restaurants.

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Organization and Description of Business - Additional Information (Details) $ / shares in Units, $ in Thousands		6 Months Ended
	Feb. 18, 2024 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2024 Restaurants $ / shares	Dec. 31, 2023 Restaurants $ / shares	Apr. 01, 2016
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of restaurants \| Restaurants			40	37
Proceeds from the issuance of class A common stock		$ 46,167
Class A Common Stock
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Common stock, par value \| $ / shares			$ 0.001	$ 0.001
Class A Common Stock \| IPO
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Stock issued price per share \| $ / shares		$ 12
Proceeds from the issuance of class A common stock		$ 46,200
Number of shares issued \| shares		4,140,000
Class B Common Stock
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Common stock, par value \| $ / shares			$ 0.001	$ 0.001
GEN LLC
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Subsidiary, Ownership Percentage, Parent			14.60%
GEN LLC \| GKBH Restaurant, LLC [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Subsidiary, Ownership Percentage, Parent	100.00%				50.00%
Total purchase price	$ 6,000
GEN Hawaii, LLC [Member] \| GKBH Restaurant, LLC [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Subsidiary, Ownership Percentage, Parent	100.00%
Equity investment ownership percentage	50.00%
Total purchase price	$ 6,000
Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Lease term			25 years
Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Lease term			10 years