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Number Of Communities Acquired

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Number Of Communities Managed By Third Party

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Acquisitions, Dispositions and Other Significant Transactions - Blackstone Venture (Details) $ in Thousands			3 Months Ended									12 Months Ended
	Apr. 30, 2018 community	Mar. 29, 2017 USD ($) community	Dec. 31, 2019 USD ($) lease	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) community	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) lease	Dec. 31, 2018 USD ($) community	Dec. 31, 2017 USD ($) community
Business Acquisition [Line Items]
Payments to acquire joint venture												$ 4,346	$ 9,124	$ 199,017
Ownership Percentage			50.00%									50.00%
Number of communities leased \| lease			242									242
Goodwill and asset impairment			$ 43,012	$ 2,094	$ 3,769	$ 391	$ 37,927	$ 5,500	$ 16,103	$ 430,363		$ 49,266	489,893	409,782
Change in valuation allowance												72,486	329
Gain (loss) on sale of assets, net			$ 4,522	$ 579	$ 2,846	$ (702)	216,660	$ 9,833	$ 23,322	$ 43,431		$ 7,245	$ 293,246	19,273
HCP, Inc.
Business Acquisition [Line Items]
Number of communities acquired \| community	5
Term of lease		12 years
Formation of the Blackstone Venture
Business Acquisition [Line Items]
Change in valuation allowance											$ 85,000
Joint Venture \| Blackstone Venture
Business Acquisition [Line Items]
Number of community leasehold interests contributed \| community		62
Payments to acquire joint venture		$ 179,200
Ownership Percentage		15.00%
Investments in unconsolidated ventures		$ 66,800
Fair value of investment		47,100
Goodwill and asset impairment		$ 19,700					33,400
Payment to complete sale of joint venture interest							2,000
Gain (loss) on sale of assets, net							$ 3,800
Joint Venture \| Blackstone Venture \| Senior Housing Communities
Business Acquisition [Line Items]
Number of communities acquired \| community		64
Purchase price		$ 1,100,000
Number of communities managed by third party \| community		2
Blackstone Venture
Business Acquisition [Line Items]
Number of communities leased \| community		2
Number of communities managed \| community		60
2 Leased Communities Owned By Joint Venture Terminated
Business Acquisition [Line Items]
Number of communities managed by third party \| community							2						2
Termination Of Triple Net Leases
Business Acquisition [Line Items]
Gain (loss) on sale of assets, net														$ 11,400
Number of communities disposed through termination of lease \| community														26
Financing lease assets, carrying value														$ 145,300
Financing lease obligations, carrying value														$ 156,700
Number of communities previously subject to sale leaseback transactions \| community														21