Securities (Summary of Volume of State and Political Subdivision Securities Held in Portfolio) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	$ 267,105	$ 276,443
Available for sale securities, Unrealized Gains	3,005	5,576
Available for sale securities, Unrealized Losses	3,568	1,227
Available for sale securities, Estimated Fair Value	266,542	$ 280,792
MICHIGAN [Member]
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	15,100
Available for sale securities, Unrealized Gains	7
Available for sale securities, Unrealized Losses	520
Available for sale securities, Estimated Fair Value	14,587
ILLINOIS
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	9,316
Available for sale securities, Unrealized Gains	181
Available for sale securities, Unrealized Losses	112
Available for sale securities, Estimated Fair Value	9,385
TEXAS
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	8,710
Available for sale securities, Unrealized Gains	14
Available for sale securities, Unrealized Losses	257
Available for sale securities, Estimated Fair Value	8,467
West Virginia [Member]
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	8,413
Available for sale securities, Unrealized Gains	17
Available for sale securities, Unrealized Losses	64
Available for sale securities, Estimated Fair Value	8,366
CALIFORNIA
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	8,248
Available for sale securities, Unrealized Gains	115
Available for sale securities, Unrealized Losses	264
Available for sale securities, Estimated Fair Value	$ 8,099

Available For Sale Securities Fair Value Disclosure 1.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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