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, 2019	Dec. 31, 2018
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	$ 28,590	$ 26,829
Unpaid Principal Balance, With an allowance recorded	37,395	32,995
Unpaid Principal Balance	65,985	59,824
Recorded Investment
Recorded Investment, With no related allowance recorded	25,107	23,477
Recorded Investment, With an allowance recorded	36,864	31,972
Recorded Investment	61,971	55,449
Allowance for loan losses, With an allowance recorded	2,512	2,312
Indirect auto
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	0	294
Unpaid Principal Balance, With an allowance recorded	0	946
Recorded Investment
Recorded Investment, With no related allowance recorded	0	292
Recorded Investment, With an allowance recorded	0	945
Allowance for loan losses, With an allowance recorded	0	26
Commercial
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	19,315	19,846
Unpaid Principal Balance, With an allowance recorded	26,821	21,845
Recorded Investment
Recorded Investment, With no related allowance recorded	17,131	17,304
Recorded Investment, With an allowance recorded	26,387	20,994
Allowance for loan losses, With an allowance recorded	1,662	1,367
Commercial \| Owner occupied commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	9,527	8,650
Unpaid Principal Balance, With an allowance recorded	11,136	11,095
Recorded Investment
Recorded Investment, With no related allowance recorded	8,118	6,546
Recorded Investment, With an allowance recorded	11,115	11,056
Allowance for loan losses, With an allowance recorded	816	862
Commercial \| Income producing commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	5,159	9,986
Unpaid Principal Balance, With an allowance recorded	13,591	6,968
Recorded Investment
Recorded Investment, With no related allowance recorded	4,956	9,881
Recorded Investment, With an allowance recorded	13,178	6,703
Allowance for loan losses, With an allowance recorded	770	402
Commercial \| Commercial & industrial
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	1,144	525
Unpaid Principal Balance, With an allowance recorded	559	1,652
Recorded Investment
Recorded Investment, With no related allowance recorded	890	370
Recorded Investment, With an allowance recorded	559	1,251
Allowance for loan losses, With an allowance recorded	21	32
Commercial \| Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	2,458	685
Unpaid Principal Balance, With an allowance recorded	1,535	2,130
Recorded Investment
Recorded Investment, With no related allowance recorded	2,140	507
Recorded Investment, With an allowance recorded	1,535	1,984
Allowance for loan losses, With an allowance recorded	55	71
Commercial \| Equipment financing
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	1,027	0
Unpaid Principal Balance, With an allowance recorded	0	0
Recorded Investment
Recorded Investment, With no related allowance recorded	1,027	0
Recorded Investment, With an allowance recorded	0	0
Allowance for loan losses, With an allowance recorded	0	0
Residential \| Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	731	554
Unpaid Principal Balance, With an allowance recorded	643	791
Recorded Investment
Recorded Investment, With no related allowance recorded	626	428
Recorded Investment, With an allowance recorded	630	779
Allowance for loan losses, With an allowance recorded	47	51
Residential \| Residential mortgage
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	7,362	5,787
Unpaid Principal Balance, With an allowance recorded	9,624	9,169
Recorded Investment
Recorded Investment, With no related allowance recorded	6,436	5,202
Recorded Investment, With an allowance recorded	9,555	9,018
Allowance for loan losses, With an allowance recorded	782	861
Residential \| Home equity lines of credit
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	1,116	330
Unpaid Principal Balance, With an allowance recorded	146	45
Recorded Investment
Recorded Investment, With no related allowance recorded	861	234
Recorded Investment, With an allowance recorded	131	42
Allowance for loan losses, With an allowance recorded	16	1
Consumer
Unpaid Principal Balance
Unpaid Principal Balance, With no related allowance recorded	66	18
Unpaid Principal Balance, With an allowance recorded	161	199
Recorded Investment
Recorded Investment, With no related allowance recorded	53	17
Recorded Investment, With an allowance recorded	161	194
Allowance for loan losses, With an allowance recorded	$ 5	$ 6

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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