Securities - Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	$ 5,282,846	$ 5,898,041
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	583	70,839
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(694,330)	(57,881)
Debt Securities, Available-for-sale	4,589,099	5,910,999
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Total	2,034,792	2,148,327
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	50
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(312,014)	(25,771)
Debt Securities, Held-to-maturity, Fair Value	1,722,778	2,122,606
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	3,188,381	3,738,616
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	382	45,077
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(429,053)	(38,092)
Debt Securities, Available-for-sale	2,759,710	3,745,601
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Total	2,034,792	2,148,327
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	50
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(312,014)	(25,771)
Debt Securities, Held-to-maturity, Fair Value	1,722,778	2,122,606
Asset-backed Securities
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	376,336	469,052
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	3,802
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(48,983)	(9,791)
Debt Securities, Available-for-sale	327,353	463,063
State and Municipal Securities
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	959,469	983,704
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	199	18,525
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(125,595)	(4,938)
Debt Securities, Available-for-sale	834,073	997,291
US Government Corporations and Agencies Securities [Member]
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	222,829	252,755
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2	3,095
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(14,062)	(3,274)
Debt Securities, Available-for-sale	208,769	252,576
US Government Securities
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	183,049	158,367
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(15,153)	(831)
Debt Securities, Available-for-sale	167,896	157,536
Non-agency collateralized mortgage obligations
Debt Securities [Line Items]
Debt Securities Available-for-Sale, Amortized Cost	352,782	295,547
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	340
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(61,484)	(955)
Debt Securities, Available-for-sale	$ 291,298	$ 294,932

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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Amount, before tax, of unrealized loss 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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