Segment Disclosures - Revenues and Assets by Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Disclosure
Total revenues	$ 483,205	$ 481,465	$ 476,238	$ 455,276	$ 431,697	$ 423,565	$ 408,559	$ 381,054	$ 1,896,184	$ 1,644,875	$ 1,240,339
Total assets	15,257,519				15,920,089				15,257,519	15,920,089
Assets held for sale and discontinued operations, net	37,190				2,626,306				37,190	2,626,306
Operating segment
Segment Disclosure
Gross assets	16,643,879				14,583,020				16,643,879	14,583,020
Accumulated depreciation and amortization	(3,125,416)				(2,658,890)				(3,125,416)	(2,658,890)
Total assets	13,518,463				11,924,130				13,518,463	11,924,130
Operating segment | Life Science
Segment Disclosure
Total revenues									715,844	569,296	440,784
Gross assets	8,257,990				7,205,949				8,257,990	7,205,949
Operating segment | Medical Office
Segment Disclosure
Total revenues									671,242	622,398	621,171
Gross assets	6,152,512				5,197,777				6,152,512	5,197,777
Operating segment | CCRC
Segment Disclosure
Total revenues									471,325	436,494	3,010
Gross assets	2,233,377				2,179,294				2,233,377	2,179,294
Operating segment | Other Non-reportable
Segment Disclosure
Total revenues									37,773	16,687	$ 175,374
Total assets	794,172				584,432				794,172	584,432
Other non-segment
Segment Disclosure
Total assets	$ 907,694				$ 785,221				$ 907,694	$ 785,221