Loans - Average Recorded Investment and Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	$ 177,734	$ 163,903
Interest Income Recognized	1,445	1,551
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	117,089	90,069
Interest Income Recognized	571	714
Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	45,611	57,710
Interest Income Recognized	720	639
Commercial real estate \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	44,789	55,493
Interest Income Recognized	719	616
Commercial real estate \| Construction
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	822	2,217
Interest Income Recognized	1	23
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	13,898	14,098
Interest Income Recognized	143	165
Consumer loans
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	1,136	2,026
Interest Income Recognized	11	33
Consumer loans \| Home equity
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	1,136	2,026
Interest Income Recognized	$ 11	$ 33

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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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