Other Debt - Summary of Maximum Borrowing Capacity and Current Gross Balances Outstanding (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Jul. 29, 2021	Apr. 16, 2021	Jan. 29, 2021	Sep. 12, 2018
Debt Instrument [Line Items]
Period end balance	$ 331,740,000	$ 302,800,000
Maximum borrowing capacity	831,818,000	653,000,000
Revolving Credit Line
Debt Instrument [Line Items]
Maximum borrowing capacity	3,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 50,000,000.0
2021 Term Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Period end balance	74,334,000	41,636,000
Maximum borrowing capacity	100,000,000	100,000,000		$ 100,000,000.0
2021 Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Period end balance	79,504,000	82,580,000
Maximum borrowing capacity	200,000,000	200,000,000			$ 200,000,000.0
July 2021 Term Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Period end balance	2,185,000
Maximum borrowing capacity	100,000,000	100,000,000	$ 100,000,000.0
2013 Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Period end balance	136,165,000	153,499,000
Maximum borrowing capacity	300,000,000.0	200,000,000
Bank Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Period end balance	29,495,000	22,385,000
Maximum borrowing capacity	50,000,000	50,000,000
2019 Term Loan | Secured Debt
Debt Instrument [Line Items]
Period end balance		2,700,000
Maximum borrowing capacity		$ 3,000,000
October 2022 Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Period end balance	10,057,000
Maximum borrowing capacity	18,818,000
September 2022 Term Repurchase Agreement | Secured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 60,000,000