Investments In Unconsolidated Joint Ventures (Red Bank Corporate Plaza, L.L.C.) (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Jul. 15, 2013	Sep. 30, 2013 Red Bank Corporate Plaza, L.L.C. [Member] sqft	Sep. 30, 2012 Red Bank Corporate Plaza, L.L.C. [Member]	Sep. 30, 2013 Red Bank Corporate Plaza, L.L.C. [Member] sqft	Sep. 30, 2012 Red Bank Corporate Plaza, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Area of property (in square feet)		92,878		92,878
Lease expiration date				Sep. 30, 2017
Percentage of interest in venture		50.00%		50.00%
Mortgage loans, carrying amount		$ 16,800,000		$ 16,800,000
Spread over LIBOR	1.25%			3.00%
Mortgage loan, maturity date				May 2016
LIBOR interest rate		0.18%		0.18%
Percentage of loan that has a fixed interest rate		75.00%		75.00%
Fixed interest rate		3.99375%		3.99375%
Management, leasing and other services fees		$ 26,000	$ 25,000	$ 80,000	$ 75,000