Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) loan	Mar. 31, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	33	53
Recorded Investment	$ 3,958	$ 54,911
Unpaid Principal Balance	$ 4,007	$ 63,163
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	2	20
Recorded Investment	$ 92	$ 52,326
Unpaid Principal Balance	$ 92	$ 60,546
Commercial real estate — owner occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Recorded Investment	$ 0	$ 204
Unpaid Principal Balance	$ 0	$ 204
Commercial real estate — investor
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	1
Recorded Investment	$ 1,007	$ 733
Unpaid Principal Balance	$ 1,037	$ 744
Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	11	16
Recorded Investment	$ 1,807	$ 1,301
Unpaid Principal Balance	$ 1,807	$ 1,322
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	17	15
Recorded Investment	$ 1,044	$ 347
Unpaid Principal Balance	$ 1,060	$ 347
Other consumer
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	2	0
Recorded Investment	$ 8	$ 0
Unpaid Principal Balance	$ 11	$ 0

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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.

+ References

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

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