| Investments In Unconsolidated Joint Ventures (Crystal House Apartments Investors LLC) (Narrative) (Details) (Crystal House Apartments Investors LLC [Member], USD $) | 0 Months Ended | 3 Months Ended | 9 Months Ended | 
|---|---|---|---|
| Mar. 20, 2013
 item | Sep. 30, 2013 | Sep. 30, 2013 | |
| Schedule of Equity Method Investments [Line Items] | |||
| Number of units | 828 | ||
| Venture property acquisition cost | $ 262,500,000 | ||
| Number of units available for development | 295 | ||
| Number of approved units available for development | 252 | ||
| Percentage of interest in venture | 25.00% | ||
| Internal rate of return | 9.00% | ||
| Mortgage loans, carrying amount | 165,000,000 | 165,000,000 | |
| Interest rate | 3.17% | 3.17% | |
| Mortgage loan, maturity date | March 2020 | ||
| Initial term of interest only payments | 5 years | ||
| Amortization schedule | 30 years | ||
| Percentage of interest in developable land | 50.00% | ||
| Management, leasing and other services fees | $ 109,000 | $ 228,000 | |
| Holding and distribution pattern under operating agreement | In general, the operating agreement of CHAI provides that net operating cash flows are distributed to the members in accordance with ownership percentages. Net cash flows from a capital event are distributed first to the members in accordance with ownership percentages until they receive a nine percent IRR, as defined, with any excess distributed 50 percent to the Company and 50 percent to UBS. | ||
| Parent Company [Member] | |||
| Schedule of Equity Method Investments [Line Items] | |||
| Percentage of capital event cash flows distributed | 50.00% | ||
| UBS Global Asset Management [Member] | |||
| Schedule of Equity Method Investments [Line Items] | |||
| Percentage of capital event cash flows distributed | 50.00% | 
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- Definition Holding And Distribution Pattern Under Operating Agreement No definition available. 
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- Definition Internal Rate of Return No definition available. 
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- Definition Management Leasing And Other Services Fees. No definition available. 
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- Definition Mortgage Loan, Initial Term Of Interest Only Payments No definition available. 
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- Definition Mortgage Loan Maturity Date No definition available. 
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- Definition Mortgage Loans, Amortization Period No definition available. 
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- Definition Number Of Approved Units Available For Development No definition available. 
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- Definition Number Of Units Available For Development No definition available. 
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- Definition Percentage Of Capital Event Cash Flows Distributed No definition available. 
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- Definition Percentage Of Interest In Developable Land No definition available. 
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- Definition Cost of property acquired by the venture. No definition available. 
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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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 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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- Definition The number of units in a real estate property owned as of the balance sheet date. No definition available. 
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- Details 
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