| Investments In Unconsolidated Joint Ventures (Gale Jefferson, L.L.C.) (Narrative) (Details) (USD $) | 0 Months Ended | 9 Months Ended | 0 Months Ended | 3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|---|---|---|
| Jul. 15, 2013 | Sep. 30, 2013 | Sep. 30, 2013
 One Jefferson [Member] | Jan. 04, 2013
 Gale Jefferson, L.L.C. [Member] | Sep. 30, 2013
 Gale Jefferson, L.L.C. [Member]
 sqft | Sep. 30, 2012
 Gale Jefferson, L.L.C. [Member] | Sep. 30, 2013
 Gale Jefferson, L.L.C. [Member]
 sqft | Sep. 30, 2012
 Gale Jefferson, L.L.C. [Member] | |
| Schedule of Equity Method Investments [Line Items] | ||||||||
| Percentage of interest in venture | 8.33% | |||||||
| Rentable Square Feet | 100,010 | 100,010 | ||||||
| Lease expiration date | Aug. 01, 2025 | |||||||
| Mortgage loans, carrying amount | $ 20,200,000 | |||||||
| Spread over LIBOR | 1.25% | 1.60% | ||||||
| Mortgage loan, maturity date | October 2013 | |||||||
| Venture sale of real estate | 3,200,000 | |||||||
| Share of gain on sale of real estate | 1,100,000 | |||||||
| Gain on sale of property | 84,930,000 | 69,000 | ||||||
| Management, leasing and other services fees | $ 0 | $ 48,000 | $ 0 | $ 144,000 | ||||
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- Definition Management Leasing And Other Services Fees. No definition available. 
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- Definition Mortgage Loan Maturity Date No definition available. 
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- Definition Share Of Gain On Sale Of Real Estate No definition available. 
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- Definition Revenue recognized by the venture from the sale of property. No definition available. 
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- Definition Area of a real estate property. No definition available. 
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. No definition available. 
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of difference between the carrying amount and the sales price of real estate properties sold as part of discontinued operations. No definition available. 
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- Definition Date which lease or group of leases is set to expire, in CCYY-MM-DD format. No definition available. 
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- Definition The carrying amount of the outstanding balance due under the mortgage loan. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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