v2.4.0.8

Organization (Details) (USD $) | 9 Months Ended |  | 9 Months Ended |  |  | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 sqft Vehicles acre Y | Sep. 30, 2013 | Sep. 30, 2014 Commercial Real Estate Properties [Member] Real_Estate_Properties sqft | Sep. 30, 2014 Total Properties Under Construction [ Member] Real_Estate_Properties sqft | Sep. 30, 2014 Total Office Properties [ Member] Real_Estate_Properties | Sep. 30, 2014 Class A Office Properties [Member] Real_Estate_Properties | Sep. 30, 2014 Office Properties Under Construction [ Member] Real_Estate_Properties | Sep. 30, 2014 Office Technical Properties [Member] Real_Estate_Properties | Sep. 30, 2014 Hotel Property [ Member] Real_Estate_Properties | Sep. 30, 2014 Retail Properties [ Member] Real_Estate_Properties | Sep. 30, 2014 Retail Properties Under Construction [Member] Real_Estate_Properties | Sep. 30, 2014 Residential Properties [Member] Real_Estate_Properties | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | Dec. 31, 2013 Series B Cumulative Redeemable Preferred Stock [Member] | Sep. 30, 2014 Depository shares of Series B Cumulative Redeemable Preferred [Member] | Sep. 30, 2014 Series Four Preferred Units [Member] | Sep. 30, 2014 Series B Preferred Units [Member]
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ratio of depository shares to shares of Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  | 0.01 |  |  |  |
General and limited partnership interest in the operating partnership (percent) | 89.50% | 89.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restriction on redemption of OP units from date of issuance (years) | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
One OP unit is equivalent to one share of Common Stock (in shares) | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
OP unit conversion rate (in shares) | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series B, Shares Outstanding |  |  |  |  |  |  |  |  |  |  |  |  | 80,000 | 80,000 | 8,000,000 |  | 80,000
Series B, Dividend Rate, Percentage |  |  |  |  |  |  |  |  |  |  |  |  | 5.25% |  |  |  |
Preferred Units Liquidation Preference |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 50.00 |
Quarterly Distributions to Series Four Preferred Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.25 |
Series Four Preferred Units Annual Dividend Payable Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% |
Number of real estate properties |  |  | 172 | 10 | 163 | 132 | 9 | 31 | 1 | 5 | 1 | 3 |  |  |  |  |
Net Rentable Area (in sf) |  |  | 46,400,000 | 3,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of vehicles in structured parking | 45,835 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of parking (in square feet) | 15,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of undeveloped land parcels owned (in acres) | 492.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition OP Unit Conversion Rate. + References No definition available. + Details
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- Definition Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055 + Details
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 + Details
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