Segment Reporting (Reconciliation of Segment Activity) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenue from tenants			$ 329,355	$ 381,612	$ 374,914
Property operating and maintenance			205,813	243,548	234,185
NOI			123,542	138,064	140,729
Impairment charges	$ (6,100)	$ (900)	(40,951)	(36,446)	(55,969)
Operating fees to related parties			(24,206)	(23,922)	(23,414)
Acquisition and transaction related			(2,714)	(173)	(362)
General and administrative			(16,828)	(21,572)	(20,530)
Depreciation and amortization			(79,926)	(81,053)	(81,032)
Gain on sale of real estate investments			3,648	5,230	8,790
Interest expense			(47,900)	(51,519)	(56,059)
Interest and other income			61	44	7
Gain (loss) on non-designated derivatives			37	(102)	(68)
Income tax expense			(203)	(4,061)	(399)
Net loss (income) attributable to non-controlling interests			260	(303)	393
Allocation for preferred stock			(7,762)	(2,968)	(173)
Net loss attributable to common stockholders			(92,942)	(78,781)	(88,087)
Medical Office Buildings
Segment Reporting Information [Line Items]
Revenue from tenants			122,867	119,824	114,943
Property operating and maintenance			34,480	32,812	34,123
NOI			88,387	87,012	80,820
Seniors Housing Communities
Segment Reporting Information [Line Items]
Revenue from tenants			206,488	261,788	259,971
Property operating and maintenance			171,333	210,736	200,062
NOI			$ 35,155	$ 51,052	$ 59,909