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Properties, Net (Details 2) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Properties |  |
Projects in development or held for future development | $ 403,494 | $ 401,531
Projects in development or held for future development [Member] | Land in development or held for future development [Member] |  |
Properties |  |
Projects in development or held for future development | 240,825 | 195,521
Projects in development or held for future development [Member] | Development in progress, excluding land [Member] |  |
Properties |  |
Projects in development or held for future development | $ 162,669 | $ 206,010

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- Definition The current amount of expenditures for a real estate project that has not yet been completed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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