Dispositions of Real Estate and Discontinued Operations - Schedule of Results of Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other income (expense):
Income tax benefit (expense)	$ 1,000	$ 10,000	$ 12,000
Held-for-sale
Revenues:
Rental and related revenues	7,535	97,877	152,576
Resident fees and services	114,936	621,253	583,653
Income from direct financing leases	0	0	20,815
Total revenues	122,471	719,130	757,044
Costs and expenses:
Interest expense	3,900	10,538	8,007
Depreciation and amortization	0	143,194	224,798
Operating	122,571	550,226	474,126
Transaction costs	76	20,426	6,780
Impairments and loan loss reserves (recoveries), net	32,736	201,344	208,229
Total costs and expenses	159,283	925,728	921,940
Other income (expense):
Gain (loss) on sales of real estate, net	414,721	460,144	22,940
Other income (expense), net	4,189	5,475	17,060
Total other income (expense), net	418,910	465,619	40,000
Income (loss) before income taxes and equity income (loss) from unconsolidated joint ventures	382,098	259,021	(124,896)
Income tax benefit (expense)	969	9,913	11,783
Equity income (loss) from unconsolidated joint ventures	5,135	(1,188)	(2,295)
Income (loss) from discontinued operations	$ 388,202	$ 267,746	$ (115,408)