Securities - Contractual Maturities of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Due in one year or less	$ 35,616
Due after one year through five years	102,542
Due after five years through ten years	106,550
Due after ten years	20,763
Available-for-Sale Debt Securities With Maturities, Amortized Cost	265,471
Amortized Cost	1,065,927	$ 900,235
Fair Value
Due in one year or less	35,824
Due after one year through five years	101,364
Due after five years through ten years	101,506
Due after ten years	21,027
Available-for-Sale Debt Securities With Maturities, Fair Value	259,721
Total Available-for-Sale Debt Securities, Fair Value	1,027,080	909,651
Collateralized mortgage obligations of U.S. government corporations and agencies
Amortized Cost
Available-for-Sale Debt Securities With Fixed Maturities	404,626
Amortized Cost	404,626	270,696
Fair Value
Available-for-Sale Debt Securities With Fixed Maturities	385,602
Total Available-for-Sale Debt Securities, Fair Value	385,602	270,294
Residential mortgage-backed securities of U.S. government corporations and agencies
Amortized Cost
Available-for-Sale Debt Securities With Fixed Maturities	54,444
Amortized Cost	54,444	57,029
Fair Value
Available-for-Sale Debt Securities With Fixed Maturities	50,446
Total Available-for-Sale Debt Securities, Fair Value	50,446	56,793
Commercial mortgage-backed securities of U.S. government corporations and agencies
Amortized Cost
Available-for-Sale Debt Securities With Fixed Maturities	340,886
Amortized Cost	340,886	336,918
Fair Value
Available-for-Sale Debt Securities With Fixed Maturities	330,811
Total Available-for-Sale Debt Securities, Fair Value	330,811	$ 341,300
Corporate bonds
Amortized Cost
Available-for-Sale Debt Securities With Fixed Maturities	500
Fair Value
Available-for-Sale Debt Securities With Fixed Maturities	$ 500