Loans and Leases and Allowance for Credit Losses - Average balances of impaired loans and income recognized on impaired loans (Details) - Loans receivable - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019
Average balances of impaired loans and income recognized on impaired loans
Average Balance	$ 54,721	$ 55,314
Interest Revenue Recognized During Impairment	760	2,246
Cash Basis Interest Revenue Received	787	2,310
Indirect auto
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,069	1,121
Interest Revenue Recognized During Impairment	14	42
Cash Basis Interest Revenue Received	14	42
Commercial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	35,180	36,222
Interest Revenue Recognized During Impairment	521	1,559
Cash Basis Interest Revenue Received	539	1,617
Commercial \| Owner occupied commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	18,759	18,302
Interest Revenue Recognized During Impairment	288	846
Cash Basis Interest Revenue Received	290	882
Commercial \| Income producing commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	10,906	12,941
Interest Revenue Recognized During Impairment	144	523
Cash Basis Interest Revenue Received	153	529
Commercial \| Commercial & industrial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	2,133	1,921
Interest Revenue Recognized During Impairment	48	74
Cash Basis Interest Revenue Received	54	89
Commercial \| Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	3,316	3,029
Interest Revenue Recognized During Impairment	38	113
Cash Basis Interest Revenue Received	39	114
Commercial \| Equipment financing
Average balances of impaired loans and income recognized on impaired loans
Average Balance	66	29
Interest Revenue Recognized During Impairment	3	3
Cash Basis Interest Revenue Received	3	3
Residential \| Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,298	1,352
Interest Revenue Recognized During Impairment	22	70
Cash Basis Interest Revenue Received	25	72
Residential \| Residential mortgage
Average balances of impaired loans and income recognized on impaired loans
Average Balance	16,669	16,134
Interest Revenue Recognized During Impairment	195	553
Cash Basis Interest Revenue Received	203	561
Residential \| Home equity lines of credit
Average balances of impaired loans and income recognized on impaired loans
Average Balance	301	288
Interest Revenue Recognized During Impairment	4	11
Cash Basis Interest Revenue Received	2	7
Consumer
Average balances of impaired loans and income recognized on impaired loans
Average Balance	204	197
Interest Revenue Recognized During Impairment	4	11
Cash Basis Interest Revenue Received	$ 4	$ 11

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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+ References

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