Loans - Average recorded investment and interest income recognized (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 76,445	$ 64,662	$ 82,717	$ 57,063
Interest income recognized	181	284	335	375
Originated
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	44,381	59,177	45,298	52,251
Interest income recognized	24	284	39	374
Originated \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	40,013	52,269	38,924	45,246
Interest income recognized	3	12	11	19
Originated \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		783		796
Originated \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,993	5,251	3,752	5,283
Interest income recognized		81		162
Originated \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		151		307
Interest income recognized		180		180
Originated \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,251	641	2,455	509
Interest income recognized	20	9	26	9
Originated \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	124	82	167	110
Interest income recognized	1	2	2	4
Acquired
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	32,064	5,485	37,419	4,812
Interest income recognized	157		296	1
Acquired \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	19,949	1,318	24,636	1,012
Interest income recognized	133		272
Acquired \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	8,141	560	8,507	497
Acquired \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,266	1,901	1,619	1,745
Acquired \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,440		1,268
Interest income recognized	15		15
Acquired \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,052	1,704	1,244	1,557
Interest income recognized	9		9	1
Acquired \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 216	$ 2	$ 145	$ 1

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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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- Definition

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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