Investments - Schedule of Available-for-sale and Held-to-Maturity Securities Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	$ 721,566	$ 710,650
Gross Unrealized Gains	5,309	2,484
Gross Unrealized Losses	(70,322)	(84,617)
Allowance for Credit Losses	(872)	(735)
Fair Value	656,553	628,517
Securities held-to-maturity, net	720,694	709,915
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	1,716,681	1,729,054
Gross Unrealized Gains	727	481
Gross Unrealized Losses	(162,299)	(193,728)
Securities available-for-sale	1,555,109	1,535,807
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	289,560	266,090
Gross Unrealized Gains	95	0
Gross Unrealized Losses	(23,950)	(28,305)
Securities available-for-sale	265,705	237,785
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	541,345	529,012
Gross Unrealized Gains	5,133	2,321
Gross Unrealized Losses	(54,232)	(65,347)
Fair Value	492,246	465,986
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	503,883	507,842
Gross Unrealized Gains	53	27
Gross Unrealized Losses	(73,243)	(90,425)
Securities available-for-sale	430,693	417,444
Agency mortgage-backed securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	55,897	57,018
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(5,566)	(6,416)
Fair Value	50,331	50,602
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	710,642	727,931
Gross Unrealized Gains	557	453
Gross Unrealized Losses	(60,748)	(68,980)
Securities available-for-sale	650,451	659,404
U.S. Treasury bills
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	203,596	213,441
Gross Unrealized Gains	22	1
Gross Unrealized Losses	(3,515)	(4,908)
Securities available-for-sale	200,103	208,534
Corporate debt securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	124,324	124,620
Gross Unrealized Gains	176	163
Gross Unrealized Losses	(10,524)	(12,854)
Fair Value	113,976	111,929
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	9,000	13,750
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(843)	(1,110)
Securities available-for-sale	$ 8,157	$ 12,640

Debt Securities, Held-To-Maturity, Net Of Allowance For Credit Losses

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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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