Dispositions, Real Property Held for Sale and Impairment - Summary of Real Property Disposition Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Real estate dispositions:
Total net book value of dispositions	$ 175,633	$ 828,866	$ 3,097,299
Gain (loss) on real estate dispositions, net	16,043	235,375	1,088,455
Net other assets (liabilities) disposed	7,820	6,081	114,274
Proceeds from real estate dispositions	199,496	1,070,322	4,300,028
Seniors Housing Operating
Real estate dispositions:
Total net book value of dispositions	85,413	112,837	1,289,769
Triple-net
Real estate dispositions:
Total net book value of dispositions	89,827	486,369	51,666
Outpatient Medical
Real estate dispositions:
Total net book value of dispositions	$ 393	$ 229,660	$ 1,755,864