Securities - AFS Contractual Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
AFS, Amortized Cost, Rolling Maturity
Due in one year or less	$ 35,135
Due after one year through five years	23,053
Due after five years through ten years	50,701
Due after ten years	71,879
Total	180,768
Amortized cost	1,753,205	$ 2,148,635
AFS, Fair Value, Rolling Maturity
Due in one year or less	34,938
Due after one year through five years	21,705
Due after five years through ten years	50,043
Due after ten years	68,130
Total	174,816
Fair Value	1,584,724	2,130,568
Residential Mortgage Backed Securities
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	474,451
Amortized cost	474,451	900,084
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	418,720
Fair Value	418,720	898,446
Commercial Mortgage Backed Securities
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	199,537
Amortized cost	199,537	219,460
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	164,838
Fair Value	164,838	210,699
Collateralized Mortgage Obligations
AFS, Amortized Cost, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	898,449
Amortized cost	898,449	926,783
AFS, Fair Value, Rolling Maturity
Mortgage-backed securities, collateralized mortgage obligations and commercial mortgage-backed securities	826,350
Fair Value	$ 826,350	$ 916,866