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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2013
Accounting Policies [Abstract] |
Schedule of the estimated useful lives of fixed assets | We depreciate our fixed assets using the straight-line method over their estimated useful lives as follows:
|  | Estimated Useful Lives
Buildings and building improvements |  | 10-40 years
Land improvements |  | 10-20 years
Tenant improvements on operating properties |  | Related lease term
Equipment and personal property |  | 3-10 years
Schedule of amortization of intangible assets and deferred revenue | We amortize the intangible assets and deferred revenue as follows:
|  | Amortization Period
Above- and below-market leases |  | Related lease terms
In-place lease value |  | Related lease terms
Tenant relationship value |  | Estimated period of time that tenant will lease space in property
Above- and below-market cost arrangements |  | Term of arrangements
Market concentration premium |  | 40 years

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- Definition Tabular disclosure of amortization periods of intangible assets and deferred revenue, by major class. + References No definition available. + Details
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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5 + Details
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