Area of a real estate property.

No definition available.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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- Definition

Contract Sales Price Per Agreement

+ References

No definition available.

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- Definition

Disposal Group, Including Discontinued Operation, Gain (Loss) On Disposal

+ References

No definition available.

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Real Estate - Properties Sold and Held for Sale (Details) ft² in Thousands, $ in Thousands							1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 21, 2020 USD ($) ft²	Dec. 19, 2019 USD ($) ft²	Aug. 27, 2019 USD ($) ft²	Aug. 21, 2019 USD ($) ft²	Jul. 23, 2019 USD ($) ft² property	Jun. 26, 2019 USD ($) ft²	Dec. 31, 2019 USD ($) ft²	Sep. 30, 2020 USD ($) ft²	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) ft²	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) ft²
Properties Sold and Held for Sale [Line Items]
(Loss) gain on sale								$ 0	$ 0	$ (7,539)	$ (1,046)
(Loss) gain on sale								$ 0	$ 339,024	$ 0	$ 339,024
Quantico Corporate Center \| Office
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²						272
Contract Sales Price						$ 33,000
(Loss) gain on sale						$ 1,000
Shopping Center Portfolio
Properties Sold and Held for Sale [Line Items]
(Loss) gain on sale					$ 333,000
Frederick Crossing and Frederick County Square
Properties Sold and Held for Sale [Line Items]
(Loss) gain on sale				$ 9,500
Centre at Hagerstown
Properties Sold and Held for Sale [Line Items]
(Loss) gain on sale			$ (3,500)
Held for sale \| John Marshall II \| Office
Properties Sold and Held for Sale [Line Items]
Contract sales price per agreement	$ 57,000						$ 63,400					$ 63,400
2020 Properties
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²								223		223
Contract Sales Price								$ 57,000		$ 57,000
(Loss) gain on sale										$ (6,855)
2020 Properties \| Disposal group, not discontinued operations \| John Marshall II \| Office
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²	223
Contract Sales Price	$ 57,000
(Loss) gain on sale	$ (6,855)
2019 Properties
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²							2,184					2,184
Contract Sales Price							$ 728,750					$ 728,750
(Loss) gain on sale												398,985
2019 Properties \| Disposal group, not discontinued operations \| Quantico Corporate Center \| Office
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²						272
Contract Sales Price						$ 33,000
(Loss) gain on sale						$ (1,046)
2019 Properties \| Disposal group, not discontinued operations \| 1776 G Street \| Office
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²		262
Contract Sales Price		$ 129,500					129,500					$ 129,500
(Loss) gain on sale		$ 61,007					$ 61,000
2019 Properties \| Discontinued operations \| Shopping Center Portfolio \| Retail
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²					800
Contract Sales Price					$ 485,250
(Loss) gain on sale					$ 333,023
Number of properties \| property					5
2019 Properties \| Discontinued operations \| Frederick Crossing and Frederick County Square \| Retail
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²				520
Contract Sales Price				$ 57,500
(Loss) gain on sale				$ 9,507
2019 Properties \| Discontinued operations \| Centre at Hagerstown \| Retail
Properties Sold and Held for Sale [Line Items]
Rentable Square Feet (sq ft) \| ft²			330
Contract Sales Price			$ 23,500
(Loss) gain on sale			$ (3,506)