Goodwill and Other Intangible Assets, Net - Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Gross Carrying Amount	$ 760,420	$ 760,420
Dispositions and Other Reductions	(49,637)	(49,637)
Accumulated Impairment	(556,652)	(205,000)
Net	154,131	505,783
Independent Living
Goodwill [Line Items]
Gross Carrying Amount	28,141	28,141
Dispositions and Other Reductions	(820)	(820)
Accumulated Impairment	0	0
Net	27,321	27,321
Assisted Living and Memory Care
Goodwill [Line Items]
Gross Carrying Amount	605,469	605,469
Dispositions and Other Reductions	(48,817)	(48,817)
Accumulated Impairment	(556,652)	(205,000)
Net	0	351,652
Health Care Services
Goodwill [Line Items]
Gross Carrying Amount	126,810	126,810
Dispositions and Other Reductions	0	0
Accumulated Impairment	0	0
Net	$ 126,810	$ 126,810