Fair Value Measurements (Narratives) (Details)	12 Months Ended
Dec. 31, 2014
Fair Value Disclosures [Abstract]
Leverage adjusted unsecured spread	1.08%
Illiquidity adjustment	0.75%

Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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