Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) - Non-Covered Loans $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 loan	Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 loan	Dec. 31, 2016 USD ($)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	1	2	1	4
Non-accrual	$ 13,150		$ 13,150		$ 13,060
Restructured	677		677		2,331
Total Recorded Investment	$ 13,827		$ 13,827		15,391
Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	1	1	1	2
Non-accrual	$ 9,608		$ 9,608		10,046
Restructured	677		677		2,311
Total Recorded Investment	$ 10,285		$ 10,285		12,357
Commercial - investor owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	0	0	0	1
Non-accrual	$ 288		$ 288		435
Restructured	0		0		0
Total Recorded Investment	$ 288		$ 288		435
Commercial - owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	0	0	0	0
Non-accrual	$ 0		$ 0		231
Restructured	0		0		0
Total Recorded Investment	$ 0		$ 0		231
Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	0	1	0	1
Non-accrual	$ 1,935		$ 1,935		2,286
Restructured	0		0		20
Total Recorded Investment	1,935		1,935		2,306
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	1,310		1,310		62
Restructured	0		0		0
Total Recorded Investment	$ 1,310		$ 1,310		62
Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	0	0	0	0
Non-accrual	$ 9		$ 9		0
Restructured	0		0		0
Total Recorded Investment	$ 9		$ 9		$ 0

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

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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The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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