Note Payable and Lines of Credit - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Current portion of note payable and lines of credit	$ 28,270	$ 33,070
Long-term portion of note payable	210,231	213,920
Steak n Shake note payable \| Notes Payable, Other Payables
Debt Instrument [Line Items]
Current portion of note payable and lines of credit	5,770	5,820
Biglari Holdings line of credit \| Line of Credit
Debt Instrument [Line Items]
Current portion of note payable and lines of credit	$ 22,500	$ 27,250

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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+ Details