Securities - Composition of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	$ 909,651	$ 770,393
Marketable equity securities	1,142	3,300
Total Securities	910,793	773,693
Total Debt Securities, Available-for-sale, Amortized Cost	900,235	737,005
Gross Unrealized Gains	15,183	33,478
Gross Unrealized Losses	(5,767)	(90)
Fair Value	909,651	770,393
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	95,327	10,282
Total Debt Securities, Available-for-sale, Amortized Cost	95,954	9,980
Gross Unrealized Gains	115	302
Gross Unrealized Losses	(742)	0
Fair Value	95,327	10,282
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	70,348	82,904
Total Debt Securities, Available-for-sale, Amortized Cost	68,599	78,755
Gross Unrealized Gains	1,749	4,149
Gross Unrealized Losses	0	0
Fair Value	70,348	82,904
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	270,294	209,296
Total Debt Securities, Available-for-sale, Amortized Cost	270,696	202,975
Gross Unrealized Gains	2,408	6,410
Gross Unrealized Losses	(2,810)	(89)
Fair Value	270,294	209,296
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	56,793	67,778
Total Debt Securities, Available-for-sale, Amortized Cost	57,029	66,960
Gross Unrealized Gains	392	818
Gross Unrealized Losses	(628)	0
Fair Value	56,793	67,778
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	341,300	273,681
Total Debt Securities, Available-for-sale, Amortized Cost	336,918	258,875
Gross Unrealized Gains	5,969	14,806
Gross Unrealized Losses	(1,587)	0
Fair Value	341,300	273,681
Corporate Obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	500	2,025
Total Debt Securities, Available-for-sale, Amortized Cost	500	2,021
Gross Unrealized Gains	0	5
Gross Unrealized Losses	0	(1)
Fair Value	500	2,025
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt securities available-for-sale	75,089	124,427
Total Debt Securities, Available-for-sale, Amortized Cost	70,539	117,439
Gross Unrealized Gains	4,550	6,988
Gross Unrealized Losses	0	0
Fair Value	$ 75,089	$ 124,427

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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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