Investments - Allowance for Credit Loss on Beneficial Interests (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Reclassification to non-credit discount from the allowance for changes in payment expectations		$ 0		$ 800,000
Investment in beneficial interests at amortized cost, net of allowance for credit losses
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for expected credit losses, beginning balance	$ 0	0	$ 0	(615,000)
Reclassification to non-credit discount from the allowance for changes in payment expectations	0	0	0	759,000
Credit loss expense on beneficial interests	0	0	0	(50,000)
Increase in allowance for expected credit losses due to decreases in the net present value of expected cash flows	0	0	0	(94,000)
Allowance for expected credit losses, ending balance	$ 0	$ 0	$ 0	$ 0