Investment Securities - Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	$ 2	$ 6
Gross Unrealized Losses	807,306	811,136
Fair Value	4,708,519	4,843,487
Debt Securities, Available-for-sale, Amortized Cost, Total	5,515,823	5,654,617
Agency residential MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	423,731	442,996
Fair Value	2,168,613	2,242,042
Debt Securities, Available-for-sale, Amortized Cost, Total	2,592,344	2,685,038
Agency commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	60,492	61,886
Fair Value	479,957	487,606
Debt Securities, Available-for-sale, Amortized Cost, Total	540,449	549,492
Agency residential CMOs
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	60,874	60,111
Fair Value	439,227	457,063
Debt Securities, Available-for-sale, Amortized Cost, Total	500,101	517,174
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	2	0
Gross Unrealized Losses	98,145	101,075
Fair Value	673,083	670,070
Debt Securities, Available-for-sale, Amortized Cost, Total	771,226	771,145
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	52,411	60,398
Fair Value	342,789	339,326
Debt Securities, Available-for-sale, Amortized Cost, Total	395,200	399,724
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	4,345	6,898
Fair Value	104,823	102,261
Debt Securities, Available-for-sale, Amortized Cost, Total	109,168	109,159
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	6
Gross Unrealized Losses	64,217	32,868
Fair Value	280,513	311,905
Debt Securities, Available-for-sale, Amortized Cost, Total	344,730	344,767
Private label commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,937	2,076
Fair Value	23,200	26,827
Debt Securities, Available-for-sale, Amortized Cost, Total	25,137	28,903
SBA securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,278	1,274
Fair Value	15,082	17,250
Debt Securities, Available-for-sale, Amortized Cost, Total	16,360	18,524
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	39,485	40,399
Fair Value	159,507	166,724
Debt Securities, Available-for-sale, Amortized Cost, Total	198,992	207,123
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	391	1,155
Fair Value	21,725	22,413
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 22,116	$ 23,568

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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