Business and Property Management Agreements with RMR (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) employee agreement jointVenture lease property	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Related Party Transaction
Number of employees | employee	0
Professional fees	$ 14,587,000	$ 12,901,000	$ 13,161,000
Number of medical office and life science properties | property	10
RMR
Related Party Transaction
Number of joint venture arrangements | jointVenture	2
Reit Management And Research
Related Party Transaction
Number of medical office and life science properties | property	10
RMR
Related Party Transaction
Business management fees incurred	$ 13,965,000	16,646,000	23,378,000
Recognized amortization of the liability	$ 2,974,000	2,974,000	2,974,000
Percentage of property management fees payable	3.00%
Construction supervision fees payable under property management agreement as a percentage of construction costs	5.00%
Property management and construction supervision fees	$ 8,886,000	10,329,000	12,504,000
Amortization of liability related to property management and construction supervision fees	797,000	797,000	797,000
Party transaction property management and construction supervision fees capitalized	$ 3,200,000	4,672,000	2,820,000
Period over which transition services will be provided by the related party after termination of the agreement	120 days
RMR | Operating Expense
Related Party Transaction
Property management and construction supervision fees	$ 5,686,000	$ 5,657,000	$ 9,684,000
RMR | Senior Living Communities
Related Party Transaction
Number of consecutive renewal terms of agreement | agreement	2
RMR | Amended Agreement
Related Party Transaction
Base management fee payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments exceeding specified amount	0.50%
Base management fee payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments up to specified amount	0.70%
Threshold amount of other real estate investments for payment of base management fee	$ 250,000,000
Base management fee payable as a percentage of average market capitalization exceeding specified amount	0.50%
Threshold amount of average market capitalization for payment of base management fee	$ 250,000,000
Base management fee payable as a percentage of average closing price per share of common shares on NYSE	0.70%
Base management fee payable as a percentage of aggregate book value of real estate assets or transferred assets	0.50%
Incentive management fee payable (as a percent)	12.00%
Period of measurement	3 years
Top consecutive trading days	10 days
Consecutive trading days	30 days
Management agreement incentive fee payable	$ 0
Incentive management fee cap on common shares	1.50%
RMR | Amended Agreement | Up C Transaction
Related Party Transaction
Number of business days notice for termination of property management agreement for convenience by the related party	60 days
Window for providing notice of termination of property management agreement for performance by the related party	60 days
Window for providing notice of termination of property management agreement for change of control by the related party	12 months
Number of terminated management agreements for convenience before termination fee is incurred | lease	1
Number of RMR LLC terminated management agreements for good cause before termination fee is incurred | lease	1
Number of terminated management agreements for a performance reason before termination fee is incurred | lease	1
Termination fee remaining term assumption	10 years
RMR | Minimum | Amended Agreement | Up C Transaction
Related Party Transaction
Termination fee term	19 years
RMR | Maximum
Related Party Transaction
Threshold amount of real estate investments for payment of base management fee	$ 250,000,000
Base management fee payable, average market capitalization	$ 250,000,000
RMR | Maximum | Amended Agreement | Up C Transaction
Related Party Transaction
Termination fee term	20 years
RMR | SNL US REIT Healthcare Index | Minimum | Amended Agreement
Related Party Transaction
Incentive management fee reduction, basis spread	2.00%
RMR | SNL US REIT Healthcare Index | Maximum | Amended Agreement
Related Party Transaction
Incentive management fee reduction, basis spread	5.00%