Investments - Schedule of Available-for-sale and Held-to-Maturity Securities Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	$ 541,597	$ 430,295
Gross Unrealized Gains	133	5,773
Gross Unrealized Losses	(48,388)	(1,396)
Allowance for Credit Losses	(558)	(614)
Fair Value	493,342	434,672
Securities held-to-maturity, net	541,039	429,681
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	1,491,748	1,358,960
Gross Unrealized Gains	1,263	15,247
Gross Unrealized Losses	(100,567)	(8,201)
Securities available-for-sale	1,392,444	1,366,006
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	247,906	175,409
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(12,322)	(1,901)
Securities available-for-sale	235,584	173,511
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	352,799	236,379
Gross Unrealized Gains	10	1,794
Gross Unrealized Losses	(40,625)	(730)
Fair Value	312,184	237,443
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	508,912	571,587
Gross Unrealized Gains	61	5,907
Gross Unrealized Losses	(59,615)	(2,410)
Securities available-for-sale	449,358	575,084
Agency mortgage-backed securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	63,281	68,105
Gross Unrealized Gains	0	940
Gross Unrealized Losses	(2,970)	(666)
Fair Value	60,311	68,379
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	607,080	509,243
Gross Unrealized Gains	1,034	8,485
Gross Unrealized Losses	(27,918)	(3,869)
Securities available-for-sale	580,196	513,859
U.S. Treasury bills
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	116,100	90,971
Gross Unrealized Gains	77	220
Gross Unrealized Losses	(596)	(21)
Securities available-for-sale	115,581	91,170
Corporate debt securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	125,517	125,811
Gross Unrealized Gains	123	3,039
Gross Unrealized Losses	(4,793)	0
Fair Value	120,847	128,850
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	11,750	11,750
Gross Unrealized Gains	91	632
Gross Unrealized Losses	(116)	0
Securities available-for-sale	$ 11,725	$ 12,382

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

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