Borrowings - Long-term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Long-term borrowings
Early debt repayment charges		$ (2,197)
2028 Subordinated Notes \| Subordinated Notes
Long-term borrowings
Aggregate principal amount	$ 4,000
Fixed rate (as a percent)	6.99%
2030 Subordinated Notes \| Subordinated Notes
Long-term borrowings
Aggregate principal amount	$ 20,000
2030 Subordinated Notes \| Subordinated Notes \| Until September 2025
Long-term borrowings
Fixed rate (as a percent)	4.875%
2030 Subordinated Notes \| Subordinated Notes \| Thereafter \| Three month SOFR
Long-term borrowings
Variable rate, basis spread (as a percent)	4.755%
Non-recourse revolving bank line of credit \| Subordinated Notes
Long-term borrowings
Revolving bank line of credit terminated	$ 50,000
Repayment of revolving bank line of credit		75,030
Repayment of FHLB advances		44,500
Early debt repayment charges		$ 2,200

Amount of credit facility terminated during the period.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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