Loans - Troubled Debt Restructurings on Financing Receivables (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 1,327	$ 1,376	$ 1,821	$ 704
Multi-Family Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	51	61	16	270
Home Equity and Improvement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	(76)	28	(326)	(122)
Consumer Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 96	$ 56	$ 274	$ 167
TDRs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	5	17	16	46
Troubled Debt Restructurings, Recorded Investment	$ 459	$ 712	$ 1,397	$ 5,855
TDRs [Member] \| 1-4 Family Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	3	2	10	14
Troubled Debt Restructurings, Recorded Investment	$ 218	$ 149	$ 1,118	$ 770
TDRs [Member] \| 1-4 Family Non Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	1	0	3
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 29	$ 0	$ 170
TDRs [Member] \| Multi-Family Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	0	0	0
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 0	$ 0	$ 0
TDRs [Member] \| Commercial Real Estate Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	4	0	11
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 335	$ 0	$ 1,849
TDRs [Member] \| Commercial Real Estate Non Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	0	0	1
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 0	$ 0	$ 44
TDRs [Member] \| Agriculture Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	0	0	0
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 0	$ 0	$ 0
TDRs [Member] \| Commercial Real Estate Other Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	0	0	0
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 0	$ 0	$ 0
TDRs [Member] \| Other Commercial Working Capital [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	1	0	2	5
Troubled Debt Restructurings, Recorded Investment	$ 101	$ 0	$ 101	$ 2,823
TDRs [Member] \| Commercial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	1	1	2	1
Troubled Debt Restructurings, Recorded Investment	$ 140	$ 66	$ 152	$ 66
TDRs [Member] \| Home Equity and Improvement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	5	2	7
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 123	$ 26	$ 123
TDRs [Member] \| Consumer Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled Debt Restructurings, Number of Loans	0	4	0	4
Troubled Debt Restructurings, Recorded Investment	$ 0	$ 10	$ 0	$ 10

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

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

+ References

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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