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AFS Securities (Amortized cost and fair value of AFS securities by contractual maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	$ 15,459
Maturing, After One Year But Within Five Years	277,303
Maturing, After Five Years But Within Ten Years	29,650
Maturing, After Ten Years	38,875
Securities With Variable Monthly Payments or Noncontractual Maturities	271,468
Amortized Cost	632,755	$ 485,710
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less, Fair value	15,394
Maturing, After One Year But Within Five Years, Fair value	251,517
Maturing, After Five Years But Within Ten Years, Fair value	27,523
Maturing, After Ten Years, Fair value	33,558
Securities With Variable Monthly Payments or Noncontractual Maturities, Fair value	253,241
Total, Fair value	581,233	490,601
States and political subdivisions [Member]
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	15,459
Maturing, After One Year But Within Five Years	45,580
Maturing, After Five Years But Within Ten Years	21,500
Maturing, After Ten Years	38,875
Securities With Variable Monthly Payments or Noncontractual Maturities	0
Amortized Cost	121,414	116,836
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	114,000	121,205
Auction rate money market preferred [Member]
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	0
Maturing, After One Year But Within Five Years	0
Maturing, After Five Years But Within Ten Years	0
Maturing, After Ten Years	0
Securities With Variable Monthly Payments or Noncontractual Maturities	3,200
Amortized Cost	3,200	3,200
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	2,479	3,242
Mortgage-backed securities [Member]
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	0
Maturing, After One Year But Within Five Years	0
Maturing, After Five Years But Within Ten Years	0
Maturing, After Ten Years	0
Securities With Variable Monthly Payments or Noncontractual Maturities	45,087
Amortized Cost	45,087	54,710
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	41,042	56,148
Collateralized mortgage obligations [Member]
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	0
Maturing, After One Year But Within Five Years	0
Maturing, After Five Years But Within Ten Years	0
Maturing, After Ten Years	0
Securities With Variable Monthly Payments or Noncontractual Maturities	223,181
Amortized Cost	223,181	90,435
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	209,720	92,301
Corporate Debt Securities
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	0
Maturing, After One Year But Within Five Years	0
Maturing, After Five Years But Within Ten Years	8,150
Maturing, After Ten Years	0
Securities With Variable Monthly Payments or Noncontractual Maturities	0
Amortized Cost	8,150	8,150
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	7,201	8,002
US Treasury Securities
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	0
Maturing, After One Year But Within Five Years	231,723
Maturing, After Five Years But Within Ten Years	0
Maturing, After Ten Years	0
Securities With Variable Monthly Payments or Noncontractual Maturities	0
Amortized Cost	231,723	212,379
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	$ 206,791	$ 209,703

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Available-for-sale Securities, Debt Maturities, With Variable Monthly Payments Or Without Single Maturity Date, Amortized Cost Basis

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Amortized cost 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
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Amount 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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