Loans Modified in Trouble Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Financing Receivable, Modifications [Line Items]
Number of Loans	6	8	4
Pre-Modification Outstanding Recorded Investment	$ 82	$ 1,279	$ 39
Post-Modification Outstanding Recorded Investment	$ 82	$ 1,279	$ 39
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
Financing Receivable, Modifications [Line Items]
Number of Loans	1	1	0
Pre-Modification Outstanding Recorded Investment	$ 38	$ 503	$ 0
Post-Modification Outstanding Recorded Investment	$ 38	$ 503	$ 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
Financing Receivable, Modifications [Line Items]
Number of Loans	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 725	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 725	$ 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
Other Consumer
Financing Receivable, Modifications [Line Items]
Number of Loans	5	6	4
Pre-Modification Outstanding Recorded Investment	$ 44	$ 51	$ 39
Post-Modification Outstanding Recorded Investment	$ 44	$ 51	$ 39
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
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 \| Other Consumer
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	1 year
Minimum \| Automobile Loan
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	3 years
Maximum \| Other Consumer
Financing Receivable, Modifications [Line Items]
Principal repayment terms, period	5 years
Maximum \| Automobile Loan
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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
-SubTopic 10
-Section 50
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
-SubTopic 10
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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.

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