Supplemental Disclosure of Cash Flow Information - Supplemental Disclosure of Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Supplemental Cash Flow Information [Abstract]
Interest paid	$ 200,308	$ 188,791	$ 204,696
Income taxes paid, net of refunds	(330)	5,923	8,878
Capital expenditures, net of related payables	196,924	176,657	185,871
Loss (gain) on debt modification and extinguishment, net	1,357	1,932	(10,896)
Accounts receivable, net	4,624	(502)	(24,277)
Investment in unconsolidated ventures	218	5,436	4,082
Prepaid expenses and other assets, net	(21,240)	(15,483)	24,707
Refundable fees and deferred revenue	(1,934)	(10,066)	62,614
Non-operating loss (gain) on sale of assets, net	(74,445)	(288,835)	(374,532)
Capital expenditures, net of related payables:
Supplemental Cash Flow Information [Abstract]
Capital expenditures, net of related payables	196,924	176,657	185,871
Trade accounts payable	(3,085)	(6,061)	4,766
Acquisition of communities from Healthpeak:
Supplemental Cash Flow Information [Abstract]
Property, plant and equipment and leasehold intangibles, net	0	0	286,734
Financing lease obligations	0	0	129,196
Operating lease right-of-use assets	0	0	(63,285)
Operating lease obligations	0	0	74,335
Loss (gain) on debt modification and extinguishment, net	0	0	(19,731)
Net cash paid	0	0	407,249
Acquisition of other assets:
Supplemental Cash Flow Information [Abstract]
Property, plant and equipment and leasehold intangibles, net	4	0	684
Financing lease obligations	6,000	0	64,260
Net cash paid	6,004	0	64,944
Proceeds from HCS Sale, net:
Supplemental Cash Flow Information [Abstract]
Trade accounts payable	0	1,387	0
Property, plant and equipment and leasehold intangibles, net	0	(1,806)	0
Operating lease right-of-use assets	0	(8,145)	0
Operating lease obligations	0	8,145	0
Accounts receivable, net	0	(57,582)	0
Investment in unconsolidated ventures	0	100,000	0
Goodwill	0	(126,810)	0
Prepaid expenses and other assets, net	0	(32,963)	0
Accrued expenses	0	25,226	0
Refundable fees and deferred revenue	0	57,314	0
Other liabilities	0	(9,165)	0
Non-operating loss (gain) on sale of assets, net	0	(286,489)	0
Net cash received	0	(312,558)	0
Proceeds from sale of CCRC Venture, net:
Supplemental Cash Flow Information [Abstract]
Investment in unconsolidated ventures	0	0	14,848
Other liabilities	0	0	(60,748)
Non-operating loss (gain) on sale of assets, net	0	0	(369,831)
Current portion of long-term debt	0	0	34,706
Net cash received	0	0	(289,225)
Proceeds from sale of other assets, net:
Supplemental Cash Flow Information [Abstract]
Property, plant and equipment and leasehold intangibles, net	(107)	(878)	(938)
Prepaid expenses and other assets, net	(1,308)	(1,983)	(1,318)
Other liabilities	1,025	(75)	(786)
Non-operating loss (gain) on sale of assets, net	(595)	(2,346)	(4,701)
Assets held for sale	(3,668)	(16,166)	(34,348)
Net cash received	(4,653)	(21,448)	(42,091)
Master Agreement with Ventas:
Supplemental Cash Flow Information [Abstract]
Property, plant and equipment and leasehold intangibles, net	0	0	(66,444)
Financing lease obligations	0	0	7,077
Operating lease right-of-use assets	0	0	(153,213)
Operating lease obligations	0	0	362,944
Other assets, net	0	0	(42,354)
Long-term debt	0	0	34,053
Additional paid-in-capital	0	0	(22,883)
Net cash received	0	0	119,180
Non-Development | Capital expenditures, net of related payables:
Supplemental Cash Flow Information [Abstract]
Capital expenditures, net of related payables	168,166	137,410	139,592
Development | Capital expenditures, net of related payables:
Supplemental Cash Flow Information [Abstract]
Capital expenditures, net of related payables	6,193	3,208	13,667
Non-development - Reimbursable | Capital expenditures, net of related payables:
Supplemental Cash Flow Information [Abstract]
Capital expenditures, net of related payables	$ 25,650	$ 42,100	$ 27,846