Real Estate - Disposal Group revenue and net income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Rental Income	$ 3,689	$ 8,127	$ 20,266	$ 24,009
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, before Income Tax	$ 2,474	$ 2,415	$ 9,376	$ 6,852

Amount before tax of income (loss) from an individually significant component disposed of or held-for-sale including the portion attributable to the noncontrolling interest. Excludes discontinued operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3A
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=64862545&loc=SL51724579-110230

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration