Portfolio Loans - Summary of Recorded Investment by Category for Portfolio Loans Restructured (Details) - Non-Covered Loans $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	7
Pre-Modification Outstanding Recorded Balance	$ 676	$ 12,395
Post-Modification Outstanding Recorded Balance	$ 676	$ 12,395
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	4
Pre-Modification Outstanding Recorded Balance	$ 676	$ 12,114
Post-Modification Outstanding Recorded Balance	$ 676	$ 12,114
CRE - investor owned
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Pre-Modification Outstanding Recorded Balance	$ 0	$ 248
Post-Modification Outstanding Recorded Balance	$ 0	$ 248
CRE - owner occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Pre-Modification Outstanding Recorded Balance	$ 0	$ 13
Post-Modification Outstanding Recorded Balance	$ 0	$ 13
Construction and land development
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Pre-Modification Outstanding Recorded Balance	$ 0	$ 20
Post-Modification Outstanding Recorded Balance	$ 0	$ 20
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0
Pre-Modification Outstanding Recorded Balance	$ 0	$ 0
Post-Modification Outstanding Recorded Balance	$ 0	$ 0
Consumer and other
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0
Pre-Modification Outstanding Recorded Balance	$ 0	$ 0
Post-Modification Outstanding Recorded Balance	$ 0	$ 0

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Number of 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 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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