Securities (Summary of Volume of State and Political Subdivision Securities Held in Portfolio) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 272,215	$ 294,251
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6,455	1,907
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,315	3,011
Debt Securities, Available-for-sale	276,355	$ 293,147
CALIFORNIA
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	21,194
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,109
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	128
Debt Securities, Available-for-sale	22,175
MICHIGAN [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	10,864
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	623
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	11,487
ILLINOIS
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	9,245
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	410
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0
Debt Securities, Available-for-sale	9,655
TEXAS
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	8,934
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	344
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	64
Debt Securities, Available-for-sale	9,214
West Virginia [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	8,490
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	206
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	7
Debt Securities, Available-for-sale	$ 8,689

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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-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
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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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