Discontinued Operations - Additional Information (Details)				12 Months Ended
		Dec. 24, 2020 USD ($) ft²	Sep. 26, 2019 USD ($) ft²	Dec. 31, 2020 USD ($)	Dec. 31, 2021 ft²
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Area of office and retail properties | ft²					13,900,000
1899 Pennsylvania Avenue [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Sale, net proceeds	[1]			$ 14,243,000
Gain (loss) on sale of property	[1],[2]			$ (12,766,000)
1899 Pennsylvania Avenue [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Area of office and retail properties | ft²		191,000
Sale agreement amount		$ 103,000,000
Sale, net proceeds		89,206,000
Gain (loss) on sale of property		$ (12,766,000)
Liberty Place [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Area of office and retail properties | ft²			172,000
Sale agreement amount			$ 154,500,000
Gain (loss) on sale of property			$ 1,140,000

[1] Represents revenues, expenses, net income, and cash flow information of 1899 Pennsylvania Avenue in the year ended December 31, 2020 and 1899 Pennsylvania Avenue and Liberty Place in the year ended December 31, 2019

[2] Represents the loss on sale of 1899 Pennsylvania Avenue in 2020 and gain on sale of Liberty Place in 2019.