Dispositions, Real Property Held for Sale and Impairment - Summary of Real Property Disposition Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Real estate dispositions:
Total dispositions	$ 52,661	$ 212,216
Gain (loss) on real estate dispositions, net	22,934	59,080
Net other assets/(liabilities) disposed	(2,027)	2,912
Proceeds from real estate dispositions	73,568	274,208
Seniors Housing Operating
Real estate dispositions:
Total dispositions	0	74,326
Triple-net
Real estate dispositions:
Total dispositions	52,661	0
Outpatient Medical
Real estate dispositions:
Total dispositions	$ 0	$ 137,890