Investments - Schedule of Available-for-sale and Held-to-Maturity Securities Reconciliation (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	$ 618,474	$ 430,295
Gross Unrealized Gains	193	5,773
Gross Unrealized Losses	(81,092)	(1,396)
Allowance for Credit Losses	(707)	(614)
Fair Value	537,575	434,672
Securities held-to-maturity, net	617,767	429,681
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	1,658,412	1,358,960
Gross Unrealized Gains	127	15,247
Gross Unrealized Losses	(165,262)	(8,201)
Securities available-for-sale	1,493,277	1,366,006
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	250,833	175,409
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(19,160)	(1,901)
Securities available-for-sale	231,673	173,511
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	433,212	236,379
Gross Unrealized Gains	57	1,794
Gross Unrealized Losses	(65,422)	(730)
Fair Value	367,847	237,443
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	510,047	571,587
Gross Unrealized Gains	21	5,907
Gross Unrealized Losses	(93,233)	(2,410)
Securities available-for-sale	416,835	575,084
Agency mortgage-backed securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	60,042	68,105
Gross Unrealized Gains	0	940
Gross Unrealized Losses	(4,763)	(666)
Fair Value	55,279	68,379
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	686,957	509,243
Gross Unrealized Gains	34	8,485
Gross Unrealized Losses	(50,203)	(3,869)
Securities available-for-sale	636,788	513,859
U.S. Treasury bills
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	196,825	90,971
Gross Unrealized Gains	35	220
Gross Unrealized Losses	(2,232)	(21)
Securities available-for-sale	194,628	91,170
Corporate debt securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	125,220	125,811
Gross Unrealized Gains	136	3,039
Gross Unrealized Losses	(10,907)	0
Fair Value	114,449	128,850
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	13,750	11,750
Gross Unrealized Gains	37	632
Gross Unrealized Losses	(434)	0
Securities available-for-sale	$ 13,353	$ 12,382

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

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