Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,129,346	$ 900,235
Gross Unrealized Gains	1,211	15,183
Gross Unrealized Losses	(63,065)	(5,767)
Fair Value	1,067,492	909,651
Interest receivable	3,700	3,300
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	145,820	95,954
Gross Unrealized Gains	155	115
Gross Unrealized Losses	(9,693)	(742)
Fair Value	136,282	95,327
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,542	68,599
Gross Unrealized Gains	7	1,749
Gross Unrealized Losses	(734)	0
Fair Value	52,815	70,348
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	456,889	270,696
Gross Unrealized Gains	312	2,408
Gross Unrealized Losses	(29,566)	(2,810)
Fair Value	427,635	270,294
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	52,289	57,029
Gross Unrealized Gains	19	392
Gross Unrealized Losses	(5,892)	(628)
Fair Value	46,416	56,793
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	350,432	336,918
Gross Unrealized Gains	263	5,969
Gross Unrealized Losses	(16,701)	(1,587)
Fair Value	333,994	341,300
Corporate obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	500	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	500	500
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	69,874	70,539
Gross Unrealized Gains	455	4,550
Gross Unrealized Losses	(479)	0
Fair Value	$ 69,850	$ 75,089

Interest Receivable, Debt Securities Available For Sale

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- Definition

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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount excluding accrued interest, of 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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