Income Taxes - Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Taxes
Unrecognized tax benefits at the beginning of year	$ 8,210,000	$ 15,529,000	$ 14,980,000
Gross increases - prior year tax positions	191,000	343,000	549,000
Gross decreases - prior year tax positions	(7,747,000)	(7,662,000)
Unrecognized tax benefits at end of year	654,000	8,210,000	15,529,000
Interest and penalties in year-end balance		607,000	976,000
Interest expense related to uncertain tax positions	$ 191,000	$ 343,000	$ 549,000