Loans and Leases and Allowance for Credit Losses - Average balances of impaired loans and income recognized on impaired loans (Details) - Loans receivable $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Average balances of impaired loans and income recognized on impaired loans
Average Balance	$ 54,328
Interest Revenue Recognized During Impairment	745
Cash Basis Interest Revenue Received	761
Indirect auto
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,190
Interest Revenue Recognized During Impairment	14
Cash Basis Interest Revenue Received	14
Commercial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	35,765
Interest Revenue Recognized During Impairment	531
Cash Basis Interest Revenue Received	543
Commercial \| Owner occupied commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	17,410
Interest Revenue Recognized During Impairment	285
Cash Basis Interest Revenue Received	284
Commercial \| Income producing commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	14,237
Interest Revenue Recognized During Impairment	193
Cash Basis Interest Revenue Received	207
Commercial \| Commercial & industrial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,716
Interest Revenue Recognized During Impairment	19
Cash Basis Interest Revenue Received	19
Commercial \| Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	2,402
Interest Revenue Recognized During Impairment	34
Cash Basis Interest Revenue Received	33
Commercial \| Equipment financing
Average balances of impaired loans and income recognized on impaired loans
Average Balance	0
Interest Revenue Recognized During Impairment	0
Cash Basis Interest Revenue Received	0
Residential \| Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,408
Interest Revenue Recognized During Impairment	24
Cash Basis Interest Revenue Received	23
Residential \| Residential mortgage
Average balances of impaired loans and income recognized on impaired loans
Average Balance	15,502
Interest Revenue Recognized During Impairment	168
Cash Basis Interest Revenue Received	174
Residential \| Home equity lines of credit
Average balances of impaired loans and income recognized on impaired loans
Average Balance	258
Interest Revenue Recognized During Impairment	4
Cash Basis Interest Revenue Received	3
Consumer
Average balances of impaired loans and income recognized on impaired loans
Average Balance	205
Interest Revenue Recognized During Impairment	4
Cash Basis Interest Revenue Received	$ 4

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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=118936363&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=118936363&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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