Investments - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Proceeds from available-for-sale debt securities			$ 29,300,000	$ 25,600,000
Gross realized gains from sales of available-for-sale debt securities	$ 0	$ 0	5,000	27,000
Gross realized losses from sales of available-for-sale debt securities	0	0	155,000	6,000
Amount payable for securities purchased	0	43,000	0	43,000
Amount receivable for securities sold	0	$ 3,000	0	$ 3,000
Gross unrealized losses to equity investments			595,000		$ 1,000,000.0
Other than temporary impairments losses, investments			0
Investments	1,700,000		1,700,000		1,200,000
Deposits held in trust accounts	7,900,000		7,900,000		8,500,000
Deposits, held in trust for collateral requirements	$ 99,900,000		$ 99,900,000		$ 76,100,000