Securities - AFS Contractual Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
AFS, Amortized Cost, Rolling Maturity
Due in one year or less	$ 34,547
Due after one year through five years	23,446
Due after five years through ten years	21,963
Due after ten years	63,478
Total	143,434
Amortized cost	1,667,837	$ 2,148,635
AFS, Fair Value, Rolling Maturity
Due in one year or less	34,413
Due after one year through five years	22,607
Due after five years through ten years	21,878
Due after ten years	60,847
Total	139,745
Fair Value	1,562,222	2,130,568
Residential Mortgage Backed Securities
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	486,800
Amortized cost	486,800	900,084
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	453,938
Fair Value	453,938	898,446
Commercial Mortgage Backed Securities
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	189,572
Amortized cost	189,572	219,460
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	166,016
Fair Value	166,016	210,699
Collateralized Mortgage Obligations
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	848,031
Amortized cost	848,031	926,783
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	802,523
Fair Value	$ 802,523	$ 916,866