Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($) loan	Jun. 30, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	23	88
Recorded Investment	$ 4,035	$ 35,020
Unpaid Principal Balance	$ 4,099	$ 56,700
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	24
Recorded Investment	$ 47	$ 30,935
Unpaid Principal Balance	$ 47	$ 52,260
Commercial real estate — owner occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	2
Recorded Investment	$ 0	$ 716
Unpaid Principal Balance	$ 0	$ 716
Commercial real estate — investor
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0
Recorded Investment	$ 984	$ 0
Unpaid Principal Balance	$ 1,031	$ 0
Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	10	36
Recorded Investment	$ 2,064	$ 2,695
Unpaid Principal Balance	$ 2,064	$ 2,805
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	10	26
Recorded Investment	$ 935	$ 674
Unpaid Principal Balance	$ 949	$ 919
Other consumer
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0
Recorded Investment	$ 5	$ 0
Unpaid Principal Balance	$ 8	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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