Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	3
Revenue	$ 782,831	$ 753,263
Segment operating income	204,309	187,502
General and administrative expense (including non-cash stock-based compensation expense)	45,732	48,619
Facility lease expense	51,496	46,127
Depreciation and amortization	86,127	84,934
Asset impairment	1,708	0
Income (loss) from operations	19,246	7,822
Total assets	5,542,324		$ 5,573,435
Goodwill	27,321		27,321
Independent Living
Segment Reporting Information [Line Items]
Goodwill	27,300		27,300
Operating Segments | Independent Living
Segment Reporting Information [Line Items]
Revenue	148,948	140,656
Segment operating income	48,643	46,833
Total assets	1,192,142		1,206,021
Operating Segments | Assisted Living and Memory Care
Segment Reporting Information [Line Items]
Revenue	510,872	488,804
Segment operating income	137,458	124,593
Total assets	3,279,194		3,315,921
Operating Segments | CCRCs
Segment Reporting Information [Line Items]
Revenue	84,421	86,272
Segment operating income	15,590	13,499
Total assets	607,107		612,521
Operating Segments | Corporate and All Other
Segment Reporting Information [Line Items]
Revenue	38,590	37,531
Segment operating income	2,618	$ 2,577
Total assets	$ 463,881		$ 438,972