Portfolio Loans - Summary of Recorded Investment by Category for Portfolio Loans Restructured and Subsequently Defaulted (Details) - Non-Covered Loans $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
Schedule of Financing Receivables, Troubled Debt Restructurings - Suibsequent Defaults [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| loan	3	0
Recorded Balance \| $	$ 348	$ 0
Commercial and industrial
Schedule of Financing Receivables, Troubled Debt Restructurings - Suibsequent Defaults [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| loan	2	0
Recorded Balance \| $	$ 343	$ 0
Residential Portfolio Segment [Member]
Schedule of Financing Receivables, Troubled Debt Restructurings - Suibsequent Defaults [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| loan	1	0
Recorded Balance \| $	$ 5	$ 0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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