Securities - Amortized Cost and Fair Value, Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 1,735,000	$ 2,400,956
Gross Unrealized Gains	241	16,120
Gross Unrealized Losses	(201,299)	(31,024)
Fair Value	1,533,942	2,386,052
Obligations of other U.S. Government agencies and corporations
Cash and Cash Equivalents [Line Items]
Amortized Cost	170,000
Gross Unrealized Gains	0
Gross Unrealized Losses	(5,340)
Fair Value	164,660
Obligations of states and political subdivisions
Cash and Cash Equivalents [Line Items]
Amortized Cost	154,066	153,847
Gross Unrealized Gains	204	5,532
Gross Unrealized Losses	(9,368)	(269)
Fair Value	144,902	159,110
Other debt securities
Cash and Cash Equivalents [Line Items]
Amortized Cost	74,885	36,515
Gross Unrealized Gains	0	1,097
Gross Unrealized Losses	(4,049)	(148)
Fair Value	70,836	37,464
U.S. Treasury securities
Cash and Cash Equivalents [Line Items]
Amortized Cost		3,007
Gross Unrealized Gains		3
Gross Unrealized Losses		0
Fair Value		3,010
Government agency mortgage backed securities \| Residential mortgage backed securities:
Cash and Cash Equivalents [Line Items]
Amortized Cost	508,415	967,497
Gross Unrealized Gains	37	7,854
Gross Unrealized Losses	(52,036)	(6,816)
Fair Value	456,416	968,535
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Cash and Cash Equivalents [Line Items]
Amortized Cost	11,166	14,717
Gross Unrealized Gains	0	365
Gross Unrealized Losses	(1,053)	(1)
Fair Value	10,113	15,081
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Cash and Cash Equivalents [Line Items]
Amortized Cost	605,033	1,008,514
Gross Unrealized Gains	0	457
Gross Unrealized Losses	(103,864)	(20,371)
Fair Value	501,169	988,600
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Cash and Cash Equivalents [Line Items]
Amortized Cost	211,435	216,859
Gross Unrealized Gains	0	812
Gross Unrealized Losses	(25,589)	(3,419)
Fair Value	$ 185,846	$ 214,252

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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