Real Estate and Other Activities - Disposals - 2023 Activity Additional Information (Detail) $ in Millions, $ in Millions						3 Months Ended		9 Months Ended
	Oct. 10, 2023 AUD ($) Facility	Jul. 11, 2023 USD ($) Facility	May 18, 2023 AUD ($) Facility	Mar. 29, 2023 Facility	Mar. 08, 2023 USD ($)	Mar. 31, 2023 USD ($) Facility	Mar. 31, 2023 AUD ($) Facility	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($) Facility
Debt Instrument [Line Items]
Number of facilities sold | Facility									15
Proceeds from sale of facilities									$ 522.0
Net impairment charge						$ 82.0
Straight-line rent receivables						37.4
Estimated fees to sell the hospitals						8.0
Accumulated other comprehensive income (loss), foreign currency translation adjustment, net of tax						13.0
Deferred gains from our interest rate swap in AOCI						$ 29.0
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]						Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax
Australia Transaction [Member]
Debt Instrument [Line Items]
Number of facilities sold | Facility			7
Number of remaining facilities sold | Facility			11
Proceeds from sale of facilities			$ 730				$ 1,200
Australia Transaction [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Number of remaining facilities sold | Facility	4
Proceeds from sale of facilities	$ 470
Australia [Member] | General Acute Care Facility [Member]
Debt Instrument [Line Items]
Number of facilities sold | Facility				11
Prime [Member]
Debt Instrument [Line Items]
Number of facilities sold | Facility						3	3
Proceeds from sale of facilities					$ 100.0
Non-cash impairment charge						$ 11.0		$ 11.0
Facilities acquired by the Prime		$ 100.0
Number of facilities acquired | Facility		3