Income Taxes - REIT Activities (Details)	6 Months Ended
Jun. 30, 2015
Maximum [Member]
Tax Credit Carryforward [Line Items]
REIT Net Operating Loss Carryover Expiration	Dec. 31, 2034
Minimum [Member]
Tax Credit Carryforward [Line Items]
REIT Net Operating Loss Carryover Expiration	Dec. 31, 2028

Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Name:	us-gaap_OperatingLossCarryforwardsExpirationDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration