Investment Securities - Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	$ 2	$ 6
Gross Unrealized Losses	956,507	811,136
Fair Value	4,487,172	4,843,487
Debt Securities, Available-for-sale, Amortized Cost, Total	5,443,677	5,654,617
Agency residential MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	535,855	442,996
Fair Value	2,000,900	2,242,042
Debt Securities, Available-for-sale, Amortized Cost, Total	2,536,755	2,685,038
Agency commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	67,572	61,886
Fair Value	470,894	487,606
Debt Securities, Available-for-sale, Amortized Cost, Total	538,466	549,492
Agency residential CMOs
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	73,326	60,111
Fair Value	417,979	457,063
Debt Securities, Available-for-sale, Amortized Cost, Total	491,305	517,174
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	2	0
Gross Unrealized Losses	107,030	101,075
Fair Value	664,202	670,070
Debt Securities, Available-for-sale, Amortized Cost, Total	771,230	771,145
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	59,826	60,398
Fair Value	336,531	339,326
Debt Securities, Available-for-sale, Amortized Cost, Total	396,357	399,724
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	3,188	6,898
Fair Value	105,980	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	59,420	32,868
Fair Value	285,288	311,905
Debt Securities, Available-for-sale, Amortized Cost, Total	344,708	344,767
Private label commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,728	2,076
Fair Value	21,653	26,827
Debt Securities, Available-for-sale, Amortized Cost, Total	23,381	28,903
SBA securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,410	1,274
Fair Value	13,808	17,250
Debt Securities, Available-for-sale, Amortized Cost, Total	15,218	18,524
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	46,824	40,399
Fair Value	148,946	166,724
Debt Securities, Available-for-sale, Amortized Cost, Total	195,770	207,123
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	328	1,155
Fair Value	20,991	22,413
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 21,319	$ 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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