Real Estate Acquisitions and Discontinued Operations (Narrative) (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
WRIT's equity interest in Joint Venture	90.00%	90.00%
Percentage of residential property to be leased to achieve project stabilization		90.00%
Federal and state income tax expense	$ 1,173,000	$ 1,173,000
Dulles Station, Phase I [Member]
Federal and state income tax expense		1,200,000
Impairment charge		600,000
650 North Glebe Road [Member]
Number of apartments in community	150	150
Projected real estate development cost		43,500,000
Capital contribution through debt		70.00%
Real estate partners equity interest in joint venture	10.00%	10.00%
Land and capitalized development costs	$ 12,800,000	$ 12,800,000

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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