Investments - Estimated Fair Value of Contractual Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Maturing within one year (remainder of year), Amortized Cost	$ 1,627
Maturing within one year, Amortized Cost	0	$ 3,513
Maturing after one year through five years, Amortized Cost	11,874	26,422
Maturing after five years through ten years, Amortized Cost	79,707	36,840
Maturing after ten years, Amortized Cost	256,330	253,936
Securities not due at a single maturity date, Amortized Cost	396,741
Amortized Cost	1,050,172	957,459
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Maturing within one year (remainder of year), Fair Value	1,640
Maturing within one year, Fair Value	0	3,547
Maturing after one year through five years, Fair Value	11,807	26,718
Maturing after five years through ten years, Fair Value	78,347	38,314
Maturing after ten years, Fair Value	248,302	265,792
Securities not due at a single maturity date, Fair Value	392,438
Fair Value, Total	1,025,032	973,314
Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Securities not due at a single maturity date, Amortized Cost	303,893	303,912
Amortized Cost	304,904	303,912
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Securities not due at a single maturity date, Fair Value	292,498	306,727
Fair Value, Total	293,418	306,727
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Securities not due at a single maturity date, Amortized Cost		332,836
Amortized Cost	396,741	332,836
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Securities not due at a single maturity date, Fair Value		332,216
Fair Value, Total	$ 392,438	$ 332,216