Segment Reporting - Segment Information for Reportable Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Revenue from contract with customer	$ 4,753,804	$ 4,173,711	$ 3,197,223
Rental income	1,556,073	1,451,786	1,374,695
Interest income	168,354	150,571	137,563
Other income	159,764	84,547	32,634
Total revenues	6,637,995	5,860,615	4,742,115
Property operating expenses	3,947,776	3,558,770	2,774,562
Consolidated net operating income (loss)	2,690,219	2,301,845	1,967,553
Depreciation and amortization	1,401,101	1,310,368	1,037,566
Interest expense	607,846	529,519	489,853
General and administrative expenses	179,091	150,390	126,727
Loss (gain) on derivatives and financial instruments, net	(2,120)	8,334	(7,333)
Loss (gain) on extinguishment of debt, net	7	680	49,874
Provision for loan losses, net	9,809	10,320	7,270
Impairment of assets	36,097	17,502	51,107
Other expenses	108,341	101,670	41,739
Income (loss) from continuing operations before income taxes and other items	350,047	173,062	170,750
Income tax (expense) benefit	(6,364)	(7,247)	(8,713)
Income (loss) from unconsolidated entities	(53,442)	(21,290)	(22,933)
Gain (loss) on real estate dispositions, net	67,898	16,043	235,375
Income (loss) from continuing operations	358,139	160,568	374,479
Net income (loss)	358,139	160,568	374,479
Total assets	44,012,166	37,893,233
Non-segment/Corporate
Segment Reporting Information [Line Items]
Revenue from contract with customer	0	0	0
Rental income	0	0	0
Interest income	0	0	0
Other income	69,868	4,934	2,992
Total revenues	69,868	4,934	2,992
Property operating expenses	18,118	16,245	8,817
Consolidated net operating income (loss)	51,750	(11,311)	(5,825)
Depreciation and amortization	0	0	0
Interest expense	540,859	475,645	426,644
General and administrative expenses	179,091	150,390	126,727
Loss (gain) on derivatives and financial instruments, net	0	0	0
Loss (gain) on extinguishment of debt, net	0	199	52,506
Provision for loan losses, net	0	0	0
Impairment of assets	0	0	0
Other expenses	4,020	20,064	7,895
Income (loss) from continuing operations before income taxes and other items	(672,220)	(657,609)	(619,597)
Income tax (expense) benefit	(6,364)	(7,247)	(8,713)
Income (loss) from unconsolidated entities	0	0	0
Gain (loss) on real estate dispositions, net	0	0	0
Income (loss) from continuing operations	(678,584)	(664,856)	(628,310)
Net income (loss)	(678,584)	(664,856)	(628,310)
Total assets	1,814,673	658,300
Seniors Housing Operating
Segment Reporting Information [Line Items]
Rental income	466,162	410,749	194,078
Seniors Housing Operating | Operating Segments
Segment Reporting Information [Line Items]
Revenue from contract with customer	4,753,804	4,173,711	3,197,223
Rental income	0	0	0
Interest income	10,096	7,867	4,231
Other income	9,743	63,839	11,796
Total revenues	4,773,643	4,245,417	3,213,250
Property operating expenses	3,655,508	3,292,045	2,529,344
Consolidated net operating income (loss)	1,118,135	953,372	683,906
Depreciation and amortization	906,771	854,800	593,565
Interest expense	56,509	34,833	39,327
General and administrative expenses	0	0	0
Loss (gain) on derivatives and financial instruments, net	0	0	0
Loss (gain) on extinguishment of debt, net	0	386	(2,628)
Provision for loan losses, net	3,197	1,039	394
Impairment of assets	24,999	13,146	22,317
Other expenses	96,972	66,026	27,132
Income (loss) from continuing operations before income taxes and other items	29,687	(16,858)	3,799
Income tax (expense) benefit	0	0	0
Income (loss) from unconsolidated entities	(69,835)	(53,318)	(39,225)
Gain (loss) on real estate dispositions, net	68,290	5,794	6,146
Income (loss) from continuing operations	28,142	(64,382)	(29,280)
Net income (loss)	28,142	(64,382)	(29,280)
Total assets	24,857,722	22,000,732
Triple-net | Operating Segments
Segment Reporting Information [Line Items]
Revenue from contract with customer	0	0	0
Rental income	814,751	782,329	761,441
Interest income	157,592	142,402	124,540
Other income	70,986	6,776	4,603
Total revenues	1,043,329	931,507	890,584
Property operating expenses	42,194	44,483	49,462
Consolidated net operating income (loss)	1,001,135	887,024	841,122
Depreciation and amortization	231,028	215,887	220,699
Interest expense	(65)	963	6,376
General and administrative expenses	0	0	0
Loss (gain) on derivatives and financial instruments, net	(2,120)	8,334	(7,333)
Loss (gain) on extinguishment of debt, net	0	80	0
Provision for loan losses, net	6,348	9,289	10,339
Impairment of assets	11,098	3,595	26,579
Other expenses	5,060	13,043	4,189
Income (loss) from continuing operations before income taxes and other items	749,786	635,833	580,273
Income tax (expense) benefit	0	0	0
Income (loss) from unconsolidated entities	16,700	34,495	20,687
Gain (loss) on real estate dispositions, net	259	16,648	135,881
Income (loss) from continuing operations	766,745	686,976	736,841
Net income (loss)	766,745	686,976	736,841
Total assets	9,985,952	8,619,314
Outpatient Medical | Operating Segments
Segment Reporting Information [Line Items]
Revenue from contract with customer	0	0	0
Rental income	741,322	669,457	613,254
Interest income	666	302	8,792
Other income	9,167	8,998	13,243
Total revenues	751,155	678,757	635,289
Property operating expenses	231,956	205,997	186,939
Consolidated net operating income (loss)	519,199	472,760	448,350
Depreciation and amortization	263,302	239,681	223,302
Interest expense	10,543	18,078	17,506
General and administrative expenses	0	0	0
Loss (gain) on derivatives and financial instruments, net	0	0	0
Loss (gain) on extinguishment of debt, net	7	15	(4)
Provision for loan losses, net	264	(8)	(3,463)
Impairment of assets	0	761	2,211
Other expenses	2,289	2,537	2,523
Income (loss) from continuing operations before income taxes and other items	242,794	211,696	206,275
Income tax (expense) benefit	0	0	0
Income (loss) from unconsolidated entities	(307)	(2,467)	(4,395)
Gain (loss) on real estate dispositions, net	(651)	(6,399)	93,348
Income (loss) from continuing operations	241,836	202,830	295,228
Net income (loss)	241,836	202,830	$ 295,228
Total assets	$ 7,353,819	$ 6,614,887