Investments - Schedule of Available-for-sale and Held-to-Maturity Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	$ 647,082	$ 430,295
Gross Unrealized Gains	149	5,773
Gross Unrealized Losses	(109,443)	(1,396)
Allowance for Credit Losses	(689)	(614)
Fair Value	537,788	434,672
Securities held-to-maturity, net	646,393	429,681
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	1,692,587	1,358,960
Gross Unrealized Gains	28	15,247
Gross Unrealized Losses	(225,703)	(8,201)
Securities available-for-sale	1,466,912	1,366,006
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	263,717	175,409
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(28,778)	(1,901)
Securities available-for-sale	234,939	173,511
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	463,941	236,379
Gross Unrealized Gains	0	1,794
Gross Unrealized Losses	(88,973)	(730)
Fair Value	374,968	237,443
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	509,274	571,587
Gross Unrealized Gains	27	5,907
Gross Unrealized Losses	(120,283)	(2,410)
Securities available-for-sale	389,018	575,084
Agency mortgage-backed securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	58,221	68,105
Gross Unrealized Gains	0	940
Gross Unrealized Losses	(6,277)	(666)
Fair Value	51,944	68,379
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	692,187	509,243
Gross Unrealized Gains	1	8,485
Gross Unrealized Losses	(70,900)	(3,869)
Securities available-for-sale	621,288	513,859
U.S. Treasury bills
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	213,659	90,971
Gross Unrealized Gains	0	220
Gross Unrealized Losses	(4,905)	(21)
Securities available-for-sale	208,754	91,170
Corporate debt securities
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	124,920	125,811
Gross Unrealized Gains	149	3,039
Gross Unrealized Losses	(14,193)	0
Fair Value	110,876	128,850
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	13,750	11,750
Gross Unrealized Gains	0	632
Gross Unrealized Losses	(837)	0
Securities available-for-sale	$ 12,913	$ 12,382

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

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