Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities..

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 67

-Paragraph 4, 5, 6, 7

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6970148&loc=SL6759159-111685

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- Definition

Estimated Development Costs

+ References

No definition available.

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- Definition

Percentage of capital contribution through debt

+ References

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- Definition

Percentage Of Residential Property To Be Leased To Achieve Project Stabilization Stage

+ References

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+ Details

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Real Estate Variable Interest Entities Narrative (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended				0 Months Ended
	Jun. 15, 2011	Jun. 15, 2011 Six Fifty North Glebe Road [Member]	Mar. 31, 2012 Six Fifty North Glebe Road [Member]	Dec. 31, 2011 Six Fifty North Glebe Road [Member]	Nov. 23, 2011 Braddock Gateway [Member]	Mar. 31, 2012 Braddock Gateway [Member]	Dec. 31, 2011 Braddock Gateway [Member]
Real Estate Properties [Line Items]
Estimated Development Costs		$ 45.0			$ 95.3
Percentage Of Capital Contribution Through Debt	70.00%	70.00%			70.00%
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage		90.00%			95.00%
Percentage Of Residential Property To Be Leased To Achieve Project Stabilization Stage		90.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		10.00%			5.00%
Inventory, Real Estate, Land and Land Development Costs			$ 13.7	$ 13.4		$ 15.1	$ 14.4