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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 45
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Cash received for the sale of real estate that is not part of an investing activity during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
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Held for Sale Held for Sale Narrative (Details)		3 Months Ended
Held for Sale Held for Sale Narrative (Details)	Feb. 08, 2018 USD ($) a Lot Project	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of assets		$ 2,746,000	$ 74,215,000
Starwood Land, L.P.. [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Projects Sold \| Project	24
Disposal group, consideration	$ 232,000,000
Net proceeds	217,506,000
Gain on sale of assets	$ 716,000
Residential Real Estate [Member] \| Starwood Land, L.P.. [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Lots \| Lot	750
Land [Member] \| Starwood Land, L.P.. [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of Land \| a	730
Multifamily [Member] \| Starwood Land, L.P.. [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Projects Sold \| Project	1
Entitled, developed and under development projects \| Starwood Land, L.P.. [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Lots \| Lot	4,000