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Investment Securities (Schedule of Investment Securities Available for Sale) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 9,722,389	$ 9,507,041
Gross Unrealized Gains	17,196	8,376
Gross Unrealized Losses	(347,193)	(414,001)
Carrying Value	9,392,392	9,101,416
Investments	9,401,071	9,130,244
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	149,875	214,796
Gross Unrealized Gains	998	165
Gross Unrealized Losses	(8,304)	(12,009)
Carrying Value	142,569	202,952
U.S. Government agency and sponsored enterprise residential MBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,721,476	2,672,554
Gross Unrealized Gains	10,330	3,607
Gross Unrealized Losses	(19,268)	(26,471)
Carrying Value	2,712,538	2,649,690
U.S. Government agency and sponsored enterprise commercial MBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	548,402	557,489
Gross Unrealized Gains	450	156
Gross Unrealized Losses	(48,527)	(61,892)
Carrying Value	500,325	495,753
Private label residential MBS and CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,586,509	2,491,033
Gross Unrealized Gains	1,502	506
Gross Unrealized Losses	(226,507)	(253,493)
Carrying Value	2,361,504	2,238,046
Private label commercial MBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,119,814	1,822,881
Gross Unrealized Gains	2,902	1,836
Gross Unrealized Losses	(27,677)	(40,688)
Carrying Value	2,095,039	1,784,029
Single family real estate-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	207,306	335,047
Gross Unrealized Gains	240	108
Gross Unrealized Losses	(4,193)	(8,074)
Carrying Value	203,353	327,081
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,119,184	1,131,088
Gross Unrealized Gains	690	1,804
Gross Unrealized Losses	(1,043)	(193)
Carrying Value	1,118,831	1,132,699
Non-mortgage asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	91,483	96,865
Gross Unrealized Gains	6	144
Gross Unrealized Losses	(1,699)	(2,555)
Carrying Value	89,790	94,454
State and municipal obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	111,897	110,388
Gross Unrealized Gains	51	13
Gross Unrealized Losses	(8,074)	(6,391)
Carrying Value	103,874	104,010
SBA securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	66,443	74,900
Gross Unrealized Gains	27	37
Gross Unrealized Losses	(1,901)	(2,235)
Carrying Value	64,569	72,702
Marketable equity securities
Debt Securities, Available-for-sale [Line Items]
Marketable equity securities	$ 8,679	$ 28,828

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