Securities Available for Sale and Held to Maturity - Contractual Maturities of Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Securities Available for Sale, Amortized Cost [Abstract]
Due in one year or less	$ 30,089
Due after one year through five years	389,528
Due after five years through ten years	14,218
Due after ten years	5,001
Total amortized cost, before mortgage-backed securities	438,836
Mortgage-backed securities	1,831,873
Securities Available for Sale, Amortized Cost	2,270,709	$ 3,256,289
Securities Available for Sale, Estimated Fair Value [Abstract]
Due in one year or less	30,208
Due after one year through five years	356,175
Due after five years through ten years	12,999
Due after ten years	4,759
Total fair value, before mortgage-backed securities	404,141
Mortgage-backed securities	1,619,941
Total	2,024,082	3,238,877
Securities Held to Maturity, Amortized Cost [Abstract]
Due in one year or less	4,169
Due after one year through five years	341
Due after five years through ten years	28,295
Due after ten years	0
Total amortized cost, before mortgage-backed securities	32,805
Mortgage-backed securities	1,461,709
Securities Held to Maturity, Amortized Cost	1,494,514	342,537
Securities Held to Maturity, Estimated Fair Value [Abstract]
Due in one year or less	4,170
Due after one year through five years	340
Due after five years through ten years	28,180
Due after ten years	0
Total fair value, before mortgage-backed securities	32,690
Mortgage-backed securities	1,373,899
Total	$ 1,406,589	$ 353,511