Loans - Average Recorded Investment and Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	$ 155,776	$ 151,292	$ 158,980	$ 132,262
Interest Income Recognized	1,162	1,035	3,722	2,944
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	87,414	70,135	88,376	49,037
Interest Income Recognized	422	300	1,348	896
Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	51,796	60,761	54,804	60,554
Interest Income Recognized	571	503	1,789	1,350
Commercial real estate \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	50,809	57,712	52,993	57,718
Interest Income Recognized	556	482	1,735	1,290
Commercial real estate \| Construction
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	987	3,049	1,811	2,836
Interest Income Recognized	15	21	54	60
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	14,112	15,630	13,707	17,851
Interest Income Recognized	152	183	502	575
Consumer loans
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	2,454	4,766	2,093	4,820
Interest Income Recognized	17	49	83	123
Consumer loans \| Home equity
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	2,454	4,766	2,093	4,820
Interest Income Recognized	$ 17	$ 49	$ 83	$ 123

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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=84173941&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=84173941&loc=d3e5258-111524

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Amount of interest income recognized on a cash-basis method of accounting 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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