Investments - Schedule of Available-for-sale and Held-to-Maturity Securities Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	$ 1,358,960	$ 882,682
Gross Unrealized Gains	15,247	30,104
Gross Unrealized Losses	(8,201)	(357)
Securities available-for-sale	1,366,006	912,429
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	430,295	488,059
Gross Unrealized Gains	5,773	13,960
Gross Unrealized Losses	(1,396)	(496)
Allowance for Credit Losses	(614)	(449)
Debt Securities, Held-to-maturity, Fair Value	434,672	501,523
debt securities, held to maturity, net of alloawance for credit losses	429,681	487,610
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	175,409	14,978
Gross Unrealized Gains	3	186
Gross Unrealized Losses	(1,901)	(3)
Securities available-for-sale	173,511	15,161
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	571,587	335,271
Gross Unrealized Gains	5,907	8,994
Gross Unrealized Losses	(2,410)	(33)
Securities available-for-sale	575,084	344,232
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	236,379	248,324
Gross Unrealized Gains	1,794	2,814
Gross Unrealized Losses	(730)	0
Debt Securities, Held-to-maturity, Fair Value	237,443	251,138
Agency mortgage-backed securities
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	509,243	506,703
Gross Unrealized Gains	8,485	20,190
Gross Unrealized Losses	(3,869)	(321)
Securities available-for-sale	513,859	526,572
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	68,105	112,742
Gross Unrealized Gains	940	2,295
Gross Unrealized Losses	(666)	(496)
Debt Securities, Held-to-maturity, Fair Value	68,379	114,541
US Treasury Bill Securities [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	11,750	14,750
Gross Unrealized Gains	632	248
Gross Unrealized Losses	0	0
Securities available-for-sale	12,382	14,998
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	90,971	10,980
Gross Unrealized Gains	220	486
Gross Unrealized Losses	(21)	0
Securities available-for-sale	91,170	11,466
Debt Securities, Held-to-maturity [Abstract]
Amortized Cost	125,811	126,993
Gross Unrealized Gains	3,039	8,851
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	$ 128,850	$ 135,844

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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