Portfolio Loans - Summary of Allowance for Loan Losses by Portfolio Class and Category (Details) - Non-Covered Loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	$ 33,441	$ 30,185	$ 27,289
Provision (provision reversal)	5,551	4,872	4,409
Losses charged off	4,335	6,091	5,556
Recoveries	2,908	4,475	4,043
Balance, end of year	37,565	33,441	30,185
Commercial and industrial
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	22,056	16,983	12,246
Provision (provision reversal)	6,569	6,976	6,707
Losses charged off	(2,303)	(3,699)	(3,738)
Recoveries	674	1,796	1,768
Balance, end of year	26,996	22,056	16,983
CRE - investor owned
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	3,484	4,382	6,600
Provision (provision reversal)	(11)	(303)	(2,063)
Losses charged off	(95)	(664)	(250)
Recoveries	42	69	95
Balance, end of year	3,420	3,484	4,382
CRE - owner occupied
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	2,969	3,135	4,096
Provision (provision reversal)	(1,202)	(1,626)	(1,517)
Losses charged off	0	(38)	(450)
Recoveries	1,123	1,498	1,006
Balance, end of year	2,890	2,969	3,135
Construction and land development
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	1,704	1,715	2,136
Provision (provision reversal)	(1,334)	(335)	(322)
Losses charged off	0	(350)	(905)
Recoveries	934	674	806
Balance, end of year	1,304	1,704	1,715
Residential real estate
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	1,796	2,830	2,019
Provision (provision reversal)	129	(58)	525
Losses charged off	(25)	(1,313)	(48)
Recoveries	123	337	334
Balance, end of year	2,023	1,796	2,830
Consumer and other
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	1,432	1,140	192
Provision (provision reversal)	1,400	218	1,079
Losses charged off	(1,912)	(27)	(165)
Recoveries	12	101	34
Balance, end of year	$ 932	$ 1,432	$ 1,140

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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