Loans Modified in Trouble Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Financing Receivable, Modifications [Line Items]
Number of Loans	8	4	5
Pre-Modification Outstanding Recorded Investment	$ 1,279	$ 39	$ 934
Post-Modification Outstanding Recorded Investment	$ 1,279	$ 39	$ 934
Subsequent Default, Number of Contracts	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	0	0
Pre-Modification Outstanding Recorded Investment	$ 503	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 503	$ 0	$ 0
Subsequent Default, Number of Contracts	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	0	1
Pre-Modification Outstanding Recorded Investment	$ 725	$ 0	$ 883
Post-Modification Outstanding Recorded Investment	$ 725	$ 0	$ 883
Subsequent Default, Number of Contracts	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	6	4	4
Pre-Modification Outstanding Recorded Investment	$ 51	$ 39	$ 51
Post-Modification Outstanding Recorded Investment	$ 51	$ 39	$ 51
Subsequent Default, Number of Contracts	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Subsequent Default, Number of Contracts	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Minimum [Member] \| Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	1 year
Minimum [Member] \| Automobile Loan [Member]
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	3 years
Maximum [Member] \| Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	5 years
Maximum [Member] \| Automobile Loan [Member]
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	7 years

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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