Loans - Average recorded investment and interest income recognized (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 88,988	$ 49,464
Interest income recognized	154	91
Originated
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	46,214	45,325
Interest income recognized	15	90
Originated \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	37,835	38,223
Interest income recognized	8	7
Originated \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		809
Originated \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5,512	5,314
Interest income recognized		81
Originated \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		463
Originated \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,658	377
Interest income recognized	6
Originated \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	210	139
Interest income recognized	1	2
Acquired
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	42,774	4,139
Interest income recognized	139	1
Acquired \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	29,324	706
Interest income recognized	139
Acquired \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	8,873	434
Acquired \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,972	1,590
Acquired \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,096
Acquired \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,436	1,409
Interest income recognized		$ 1
Acquired \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 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=66008989&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=66008989&loc=d3e5258-111524

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Amount of interest income recognized 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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