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AFS Securities (Amortized cost and fair value of AFS securities by contractual maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	$ 16,183
Maturing, After One Year But Within Five Years	278,516
Maturing, After Five Years But Within Ten Years	29,745
Maturing, After Ten Years	38,368
Securities With Variable Monthly Payments or Noncontractual Maturities	223,485
Amortized Cost	586,297	$ 485,710
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less, Fair value	16,227
Maturing, After One Year But Within Five Years, Fair value	261,358
Maturing, After Five Years But Within Ten Years, Fair value	28,757
Maturing, After Ten Years, Fair value	35,383
Securities With Variable Monthly Payments or Noncontractual Maturities, Fair value	215,865
Total, Fair value	557,590	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	16,183
Maturing, After One Year But Within Five Years	46,692
Maturing, After Five Years But Within Ten Years	21,595
Maturing, After Ten Years	38,368
Securities With Variable Monthly Payments or Noncontractual Maturities	0
Amortized Cost	122,838	116,836
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	119,649	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	2,497	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	47,483
Amortized Cost	47,483	54,710
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	45,796	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	172,802
Amortized Cost	172,802	90,435
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	167,572	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	7,602	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	231,824
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	231,824	212,379
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Total, Fair value	$ 214,474	$ 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 http://asc.fasb.org/extlink&oid=123581744&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
-Paragraph 1
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-Topic 326
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-Topic 320
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