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, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	$ 30,185	$ 27,289	$ 34,330
Provision (provision reversal)	4,872	4,409	(642)
Losses charged off	6,091	5,556	10,378
Recoveries	4,475	4,043	3,979
Balance, end of year	33,441	30,185	27,289
Commercial and industrial
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	16,983	12,246	10,064
Provision (provision reversal)	6,976	6,707	3,810
Losses charged off	(3,699)	(3,738)	(3,404)
Recoveries	1,796	1,768	1,776
Balance, end of year	22,056	16,983	12,246
CRE - investor owned
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	3,135	4,096	4,192
Provision (provision reversal)	(1,626)	(1,517)	410
Losses charged off	(38)	(450)	(550)
Recoveries	1,498	1,006	44
Balance, end of year	2,969	3,135	4,096
CRE - owner occupied
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	4,382	6,600	10,403
Provision (provision reversal)	(303)	(2,063)	(94)
Losses charged off	664	(250)	(4,441)
Recoveries	69	95	732
Balance, end of year	3,484	4,382	6,600
Construction and land development
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	1,715	2,136	5,239
Provision (provision reversal)	(335)	(322)	(2,695)
Losses charged off	(350)	(905)	(896)
Recoveries	674	806	488
Balance, end of year	1,704	1,715	2,136
Residential real estate
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	2,830	2,019	2,026
Provision (provision reversal)	(58)	525	107
Losses charged off	(1,313)	(48)	(1,053)
Recoveries	337	334	939
Balance, end of year	1,796	2,830	2,019
Consumer and other
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	1,140	192	31
Provision (provision reversal)	218	1,079	195
Losses charged off	(27)	(165)	(34)
Recoveries	101	34	0
Balance, end of year	1,432	1,140	192
Unallocated
Allowance for Loan Losses [Roll Forward]
Balance, beginning of year	0	0	2,375
Provision (provision reversal)	0	0	(2,375)
Losses charged off	0	0	0
Recoveries	0	0	0
Balance, end of year	$ 0	$ 0	$ 0

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

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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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