Investments In Unconsolidated Joint Ventures (South Pier At Harborside - Hotel) (Details) (Harborside South Pier [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2011
Harborside South Pier [Member]
Percentage of interest in venture	50.00%
Mortgage loans, carrying amount	$ 65.4
Interest rate	6.15%
Mortgage loan maturity date	November 2016
Bears interest at fixed rate range, minimum	6.09%
Bears interest at fixed rate range, maximum	6.62%
Letter of credit	5.5
Book value of company's long-term debt	$ 5.5
Loan maturity date	Aug. 01, 2020

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