Real Estate - Real Estate Investments (Details) $ in Millions	1 Months Ended
	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	May 31, 2022 USD ($) property	Mar. 31, 2022 USD ($) property	Jan. 31, 2022 USD ($)
Life Science | MASSACHUSETTS
Real Estate [Line Items]
Payments to acquire real estate	$ 9	$ 18			$ 72
Life Science | CALIFORNIA
Real Estate [Line Items]
Payments to acquire real estate					$ 24
Medical Office Buildings | TEXAS
Real Estate [Line Items]
Payments to acquire real estate				$ 43
Number of properties acquired | property				2
Medical Office Buildings | ARKANSAS
Real Estate [Line Items]
Payments to acquire real estate			$ 26
Number of properties acquired | property			1