Real Estate and Other Activities - Investments in Unconsolidated Operating Entities - Additional Information (Details) SFr in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CHF (SFr)	Dec. 31, 2022 USD ($)
Swiss Medical Network [Member]
Business Acquisition [Line Items]
Favorable fair market value adjustment on investment | SFr		SFr 20
PHP Holdings Equity Investment [Member]
Business Acquisition [Line Items]
Favorable fair market value adjustment on investment	$ 45.0
COVID-19 Pandemic [Member] | Other [Member]
Business Acquisition [Line Items]
Favorable non-cash fair value adjustment on investment	$ 45.0		$ 2.3