Loans - Average recorded investment and interest income recognized (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 64,206	$ 16,661
Interest income recognized	1,065	364
Originated
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	45,753	14,833
Interest income recognized	950	349
Originated \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	37,697	10,131
Interest income recognized	336	27
Originated \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,016	1,092
Interest income recognized	73	20
Originated \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	6,088	2,278
Interest income recognized	344	44
Originated \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	153	568
Interest income recognized	180	15
Originated \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	629	601
Interest income recognized	9	233
Originated \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	170	163
Interest income recognized	8	10
Acquired
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	18,453	1,828
Interest income recognized	115	15
Acquired \| Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	12,463	445
Interest income recognized	25	8
Acquired \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,459
Acquired \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,704	903
Interest income recognized	42
Acquired \| Construction, land & land development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	198
Acquired \| Residential mortgage
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,624	479
Interest income recognized	48	7
Acquired \| Consumer and other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5	$ 1
Interest income recognized	$ 0

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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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