Loans Modified in Trouble Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) contract loan portfolio_category	Dec. 31, 2018 USD ($) contract loan	Dec. 31, 2017 USD ($) contract loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loan portfolio categories \| portfolio_category	4
Number of Loans \| loan	6	6	8
Pre-Modification Outstanding Recorded Investment	$ 68	$ 82	$ 1,279
Post-Modification Outstanding Recorded Investment	$ 68	$ 82	$ 1,279
Subsequent Default, Number of Contracts \| contract	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 38	$ 503
Post-Modification Outstanding Recorded Investment	$ 0	$ 38	$ 503
Subsequent Default, Number of Contracts \| contract	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, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 725
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 725
Subsequent Default, Number of Contracts \| contract	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, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	6	5	6
Pre-Modification Outstanding Recorded Investment	$ 68	$ 44	$ 51
Post-Modification Outstanding Recorded Investment	$ 68	$ 44	$ 51
Subsequent Default, Number of Contracts \| contract	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Other Consumer \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal repayment terms, period	1 year
Other Consumer \| Maximum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal repayment terms, period	5 years
Residential Portfolio Segment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Subsequent Default, Number of Contracts \| contract	0	0	0
Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0
Commitments to lend additional funds to modified loans	$ 0	$ 0	$ 0
Automobile Loan \| Minimum
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal repayment terms, period	3 years
Automobile Loan \| Maximum
Financing Receivable, Troubled Debt Restructuring [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://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554

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