Loans and Allowance for Loan Losses (Details 10) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commercial
Loans evaluated for impairment by loan segment
Recorded Investment, With no related allowance recorded	$ 65	$ 106
Recorded Investment, With related allowance recorded	5,516
Recorded Investment, Total	5,581	106
Unpaid Principal Balance, with no related allowance	65	106
Unpaid Principal Balance, with related allowance	5,516
Unpaid Principal Balance, Total	5,581	106
Related Allowance, with related allowance	625
Related Allowance, Total	625
Average Recorded Investment, with no related allowance recorded	85	146	$ 322
Average Recorded Investment, with related allowance recorded	460	279	1,341
Average Recorded Investment, Total	545	425	1,663
Interest Income Recognized, with no related allowance	6	8	13
Interest Income Recognized, with related allowance	0	0	0
Interest Income Recognized, Total	6	8	13
Commercial real estate
Loans evaluated for impairment by loan segment
Recorded Investment, With no related allowance recorded	4,664	5,681
Recorded Investment, With related allowance recorded		1,179
Recorded Investment, Total	4,664	6,860
Unpaid Principal Balance, with no related allowance	4,742	5,789
Unpaid Principal Balance, with related allowance		1,179
Unpaid Principal Balance, Total	4,742	6,968
Related Allowance, with related allowance		178
Related Allowance, Total		178
Average Recorded Investment, with no related allowance recorded	5,062	6,072	4,842
Average Recorded Investment, with related allowance recorded	527	1,209	1,160
Average Recorded Investment, Total	5,589	7,281	6,002
Interest Income Recognized, with no related allowance	291	335	181
Interest Income Recognized, with related allowance	0	85	84
Interest Income Recognized, Total	$ 291	$ 420	$ 265

Impaired financing receivable with related and no related allowance.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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- References

No definition available.

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- Definition

Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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