Discontinued Operations - Schedule of Cash Flows from Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
1899 Pennsylvania Avenue [Member]
Statements of Cash Flows:
Cash (used in) provided by operating activities	$ (2,448)
Additional Cash Flow information:
Depreciation and amortization	$ 690
1899 Pennsylvania Avenue and Liberty Place [Member]
Statements of Cash Flows:
Cash (used in) provided by operating activities		$ 2,648
Cash used in investing activities		(224)
Additional Cash Flow information:
Depreciation and amortization		2,377
Additions to real estate		$ (224)

Amount of capital expenditure attributable to discontinued operations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(2)
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Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
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Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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