Investing Receivables - Investing Receivables (Details) - Investing Receivables - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis	$ 84,884	$ 83,889
Allowance for credit losses	(2,361)	(2,377)	$ (2,937)	$ (2,794)
Investing receivables, net	82,523	81,512
Notes receivable from the City of Huntsville
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis	78,017	77,022
Other investing loan receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis	$ 6,867	$ 6,867