Commitments and Contingencies - Residential Mortgage Loans Sold with Recourse Obligations (Details) (Obligation to repurchase loans sold, USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Obligation to repurchase loans sold
Loss Contingencies
Loss contingency, estimate of possible loss	$ 4,486	$ 5,871

No authoritative reference available.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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