Debt Securities - Maturity Schedule (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-Sale, Amortized Cost
Due within one year	$ 2,211
Due after one year through five years	854,342
Due after five years through ten years	55,039
Due after ten years	60,019
Total before mortgage-backed securities	971,611
Mortgage-backed securities	4,958,492
Amortized Cost	5,930,103	$ 9,175,423
Available-for-Sale, Fair Value
Due within one year	2,193
Due after one year through five years	778,697
Due after five years through ten years	53,075
Due after ten years	57,228
Total before mortgage-backed securities	891,193
Mortgage-backed securities	4,416,114
Fair Value	5,307,307	9,170,849
Held-to-Maturity, Amortized Cost
Due within one year	2,845
Due after one year through five years	658,446
Due after five years through ten years	409,209
Due after ten years	1,458,186
Total before mortgage-backed securities	2,528,686
Mortgage-backed securities	1,186,366
Amortized Cost	3,715,052	1,199,164
Held-to-Maturity, Fair Value
Due within one year	2,836
Due after one year through five years	600,431
Due after five years through ten years	371,607
Due after ten years	1,222,828
Total before mortgage-backed securities	2,197,702
Mortgage-backed securities	1,077,090
Fair Value	$ 3,274,792	$ 1,220,883