Acquisitions and Divestitures - Additional Information (Detail) $ in Thousands	1 Months Ended		9 Months Ended
	Jun. 30, 2021 USD ($)	May 31, 2021 USD ($) ft² Time	Sep. 30, 2021 USD ($) Time	Sep. 30, 2020 Acquisition Disposition	Nov. 01, 2021 USD ($)
Business Acquisitions And Dispositions [Line Items]
Gain on sale of real estate assets			$ 1,304
Number of acquisitions | Acquisition				0
Number of dispositions | Disposition				0
Universal Health Services, Inc
Business Acquisitions And Dispositions [Line Items]
Number of term renewal options | Time		2	6
Additional renewal terms			5 years
Rentable square feet | ft²		44,000
Fire Mesa Office Building [Member] | Universal Health Services, Inc
Business Acquisitions And Dispositions [Line Items]
Total purchase price		$ 12,900
Percentage of building area leased		100.00%
Additional renewal terms		5 years
Auburn Medical Office Building II | Subsequent Event
Business Acquisitions And Dispositions [Line Items]
Sale price					$ 25,100
Medical Office Buildings
Business Acquisitions And Dispositions [Line Items]
Sale price net of closing costs	$ 3,200
Gain on sale of real estate assets			$ 1,300