Loans - Average Recorded Investment and Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	$ 157,355	$ 131,515	$ 160,611	$ 122,642
Interest Income Recognized	1,009	1,009	2,560	1,909
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	87,674	46,283	88,865	38,371
Interest Income Recognized	212	288	926	596
Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	54,973	62,878	56,334	60,450
Interest Income Recognized	579	503	1,218	847
Commercial real estate \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	52,729	60,119	54,104	57,722
Interest Income Recognized	563	483	1,179	808
Commercial real estate \| Construction
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	2,244	2,759	2,230	2,728
Interest Income Recognized	16	20	39	39
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	12,914	17,555	13,502	18,974
Interest Income Recognized	185	184	350	392
Consumer loans
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	1,794	4,799	1,910	4,847
Interest Income Recognized	33	34	66	74
Consumer loans \| Home equity
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	1,794	4,799	1,910	4,847
Interest Income Recognized	$ 33	$ 34	$ 66	$ 74

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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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