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AFS Securities (Amortized cost and fair value of AFS securities by contractual maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	$ 28,932
Maturing, After One Year But Within Five Years	70,795
Maturing, After Five Years But Within Ten Years	38,342
Maturing, After Ten Years	26,936
Securities With Variable Monthly Payments or Noncontractual Maturities	258,975
Amortized Cost	423,980	$ 501,245
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less, Fair value	29,091
Maturing, After One Year But Within Five Years, Fair value	72,332
Maturing, After Five Years But Within Ten Years, Fair value	39,875
Maturing, After Ten Years, Fair value	28,454
Securities With Variable Monthly Payments or Noncontractual Maturities, Fair value	260,087
Total, Fair value	429,839	$ 494,834
States and political subdivisions [Member]
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]
Maturing, Due in One Year or Less	28,932
Maturing, After One Year But Within Five Years	70,795
Maturing, After Five Years But Within Ten Years	38,342
Maturing, After Ten Years	26,936
Securities With Variable Monthly Payments or Noncontractual Maturities	0
Amortized Cost	165,005
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
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	139,831
Amortized Cost	139,831
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	115,944
Amortized Cost	$ 115,944

X

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Available-for-sale Securities, With Variable Monthly Payments Or Without Single Maturity Date, Fair Value

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Amortized cost of investment in debt security, measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in rolling sixth through tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Fair value of investment in debt security, measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in rolling sixth through tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year through fifth year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security, measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year through fifth year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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