Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) loan	Mar. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	53	59
Recorded Investment	$ 54,911	$ 4,498
Unpaid Principal Balance	$ 63,163	$ 4,710
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	20	7
Recorded Investment	$ 52,326	$ 1,483
Unpaid Principal Balance	$ 60,546	$ 1,522
Commercial real estate — owner occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	1
Recorded Investment	$ 204	$ 125
Unpaid Principal Balance	$ 204	$ 130
Commercial real estate — investor
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0
Recorded Investment	$ 733	$ 0
Unpaid Principal Balance	$ 744	$ 0
Real estate construction
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Recorded Investment	$ 0	$ 10
Unpaid Principal Balance	$ 0	$ 55
Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	16	30
Recorded Investment	$ 1,301	$ 2,062
Unpaid Principal Balance	$ 1,322	$ 2,124
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	15	20
Recorded Investment	$ 347	$ 818
Unpaid Principal Balance	$ 347	$ 879

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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=66008989&loc=SL6953676-111524

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

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