Noncontrolling Interests Noncontrolling Interests Textual (Details) (USD $)	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Noncontrolling Interest [Line Items]
Opertating partnership units issued	522,032
OP units remaining	74,083
Payments for repurchase of redeemable noncontrolling interest	$ 1,400,000
OP units redeemed	0	0
Equity interest	100.00%
Redemption of minority interest	10.00%
Decrease in equity for purchase of noncontrolling interest	(4,500,000)
Related party amount of transaction		93,200,000
Bethesda [Member] [Member]
Noncontrolling Interest [Line Items]
Equity interest	97.00%
Area of land	2.5
Contribution	12,200,000
Real estate units intended to develop	140
Square feet of space	7,000
Germantown [Member]
Noncontrolling Interest [Line Items]
Equity interest	90.00%
Contribution	$ 9,400,000
Real estate units intended to develop	242

Mnority Interest Onwership Percentage By Parent, Funded, Subsequent Month

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- Definition

Opertating partnership units issued

+ References

No definition available.

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- Definition

Real Estate Units Intended To Develop

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No definition available.

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- Definition

Area of land held.

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No definition available.

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- Definition

Area of a real estate property.

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No definition available.

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- Definition

Developers, builders, governmental agencies and municipalities will provide the entity with cash, or in some cases property, to extend its services to their properties. Nonrefundable contributions are recorded as contributions in aid of construction ("CIAC").

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No definition available.

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

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

-Publisher FASB

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-Topic 505

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-Subparagraph (SX 210.3-04)

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

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The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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- Definition

The cash outflow during the period for redemption of redeemable noncontrolling interests.

+ References

No definition available.

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- Definition

Amount of transactions with related party during the financial reporting period.

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