Loans and Leases and Allowance for Credit Losses - Loans individually evaluated for impairment by class of loans (Details) - Loans Receivable - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	$ 26,829	$ 10,191
Unpaid Principal Balance, With an allowance recorded	32,995	54,540
Unpaid Principal Balance	59,824	64,731
Recorded Investment
Recorded Investment, With no related allowance recorded	23,477	9,368
Recorded Investment, With an allowance recorded	31,972	52,942
Recorded Investment	55,449	62,310
Allowance for loan losses, With an allowance recorded	2,312	3,256
Home equity lines of credit
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	330	393
Unpaid Principal Balance, With an allowance recorded	45	0
Recorded Investment
Recorded Investment, With no related allowance recorded	234	101
Recorded Investment, With an allowance recorded	42	0
Allowance for loan losses, With an allowance recorded	1	0
Indirect auto
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	294	1,396
Unpaid Principal Balance, With an allowance recorded	946	0
Recorded Investment
Recorded Investment, With no related allowance recorded	292	1,396
Recorded Investment, With an allowance recorded	945	0
Allowance for loan losses, With an allowance recorded	26	0
Commercial
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	19,846	5,307
Unpaid Principal Balance, With an allowance recorded	21,845	40,885
Recorded Investment
Recorded Investment, With no related allowance recorded	17,304	4,946
Recorded Investment, With an allowance recorded	20,994	39,827
Allowance for loan losses, With an allowance recorded	1,367	2,000
Commercial \| Owner occupied commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	8,650	1,238
Unpaid Principal Balance, With an allowance recorded	11,095	21,262
Recorded Investment
Recorded Investment, With no related allowance recorded	6,546	1,176
Recorded Investment, With an allowance recorded	11,056	20,647
Allowance for loan losses, With an allowance recorded	862	1,255
Commercial \| Income producing commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	9,986	2,177
Unpaid Principal Balance, With an allowance recorded	6,968	14,419
Recorded Investment
Recorded Investment, With no related allowance recorded	9,881	2,165
Recorded Investment, With an allowance recorded	6,703	14,318
Allowance for loan losses, With an allowance recorded	402	562
Commercial \| Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	685	134
Unpaid Principal Balance, With an allowance recorded	2,130	3,917
Recorded Investment
Recorded Investment, With no related allowance recorded	507	134
Recorded Investment, With an allowance recorded	1,984	3,679
Allowance for loan losses, With an allowance recorded	71	156
Commercial \| Equipment financing
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	0	0
Unpaid Principal Balance, With an allowance recorded	0	0
Recorded Investment
Recorded Investment, With no related allowance recorded	0	0
Recorded Investment, With an allowance recorded	0	0
Allowance for loan losses, With an allowance recorded	0	0
Commercial \| Commercial & industrial
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	525	1,758
Unpaid Principal Balance, With an allowance recorded	1,652	1,287
Recorded Investment
Recorded Investment, With no related allowance recorded	370	1,471
Recorded Investment, With an allowance recorded	1,251	1,183
Allowance for loan losses, With an allowance recorded	32	27
Residential \| Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	554	405
Unpaid Principal Balance, With an allowance recorded	791	1,325
Recorded Investment
Recorded Investment, With no related allowance recorded	428	330
Recorded Investment, With an allowance recorded	779	1,247
Allowance for loan losses, With an allowance recorded	51	75
Residential \| Residential mortgage
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	5,787	2,661
Unpaid Principal Balance, With an allowance recorded	9,169	12,086
Recorded Investment
Recorded Investment, With no related allowance recorded	5,202	2,566
Recorded Investment, With an allowance recorded	9,018	11,627
Allowance for loan losses, With an allowance recorded	861	1,174
Consumer direct
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	18	29
Unpaid Principal Balance, With an allowance recorded	199	244
Recorded Investment
Recorded Investment, With no related allowance recorded	17	29
Recorded Investment, With an allowance recorded	194	241
Allowance for loan losses, With an allowance recorded	$ 6	$ 7

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

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

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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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

Amount of unpaid principal balance 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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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Unpaid principal balance of impaired financing receivables for which there is 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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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