Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Outstanding repurchase request		$ 543
Reserve for Off-balance Sheet Activities [Member] \| Residential Mortgage [Member]
Loss Contingencies [Line Items]
Valuation allowances and reserves, balance	$ 1,900	$ 2,100

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant