Investment Securities Available for Sale - Schedule Of Unrealized Loss On Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	$ 1,088,423	$ 409,725
Less than 12 months, gross unrealized losses	(5,877)	(2,666)
12 months or longer, fair value	7,580,118	7,513,154
12 months or longer, gross unrealized losses	(1,459,815)	(1,331,466)
Total, fair value	8,668,541	7,922,879
Total, gross unrealized losses	(1,465,692)	(1,334,132)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	465,387
Less than 12 months, gross unrealized losses	(1,133)
12 months or longer, fair value	0
12 months or longer, gross unrealized losses	0
Total, fair value	465,387
Total, gross unrealized losses	(1,133)
U.S. Government agency securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, gross unrealized losses	0	0
12 months or longer, fair value	28,783	28,940
12 months or longer, gross unrealized losses	(1,210)	(1,053)
Total, fair value	28,783	28,940
Total, gross unrealized losses	(1,210)	(1,053)
Mortgage-backed securities issued by U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	132,795	159,402
Less than 12 months, gross unrealized losses	(712)	(1,268)
12 months or longer, fair value	696,870	565,358
12 months or longer, gross unrealized losses	(111,370)	(96,717)
Total, fair value	829,665	724,760
Total, gross unrealized losses	(112,082)	(97,985)
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	129,505	215,917
Less than 12 months, gross unrealized losses	(2,158)	(1,193)
12 months or longer, fair value	6,005,861	6,045,914
12 months or longer, gross unrealized losses	(1,198,664)	(1,093,019)
Total, fair value	6,135,366	6,261,831
Total, gross unrealized losses	(1,200,822)	(1,094,212)
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, gross unrealized losses	0	0
12 months or longer, fair value	564,940	587,595
12 months or longer, gross unrealized losses	(111,832)	(104,892)
Total, fair value	564,940	587,595
Total, gross unrealized losses	(111,832)	(104,892)
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	360,736	34,406
Less than 12 months, gross unrealized losses	(1,874)	(205)
12 months or longer, fair value	274,840	276,675
12 months or longer, gross unrealized losses	(36,529)	(35,448)
Total, fair value	635,576	311,081
Total, gross unrealized losses	(38,403)	(35,653)
Corporate debt securities and other debt securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, gross unrealized losses	0	0
12 months or longer, fair value	8,824	8,672
12 months or longer, gross unrealized losses	(210)	(337)
Total, fair value	8,824	8,672
Total, gross unrealized losses	$ (210)	$ (337)