Real Estate Properties - Unconsolidated Joint Ventures (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) ft² property joint_venture	Dec. 31, 2023 USD ($)
Real Estate [Line Items]
Number of joint ventures | joint_venture	1
Unconsolidated Properties
Real Estate [Line Items]
Number of Properties (in properties) | property	3
OPI Carrying Value of Investments	$ 17,370	$ 18,128
Rentable Square Feet (in square feet) | ft²	471,000
Equity method investment, difference between carrying amount and underlying equity	$ 673
Unconsolidated Properties | Mortgage Note Payable
Real Estate [Line Items]
Interest rate (as a percent)	3.93%
Principal balance	$ 50,000	82,000
Unconsolidated Properties | Prosperity Metro Plaza
Real Estate [Line Items]
Number of Properties (in properties) | property	2
OPI Ownership	51.00%
OPI Carrying Value of Investments	$ 17,370	18,128
Rentable Square Feet (in square feet) | ft²	346,000
Unconsolidated Properties | Prosperity Metro Plaza | Mortgage Note Payable
Real Estate [Line Items]
Interest rate (as a percent)	4.09%
Principal balance	$ 50,000	50,000
Unconsolidated Properties | 1750 H Street, NW
Real Estate [Line Items]
Number of Properties (in properties) | property	1
OPI Ownership	50.00%
OPI Carrying Value of Investments	$ 0	0
Rentable Square Feet (in square feet) | ft²	125,000
Unconsolidated Properties | 1750 H Street, NW | Mortgage Note Payable
Real Estate [Line Items]
Interest rate (as a percent)	3.69%
Principal balance	$ 0	$ 32,000