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Equity Method Investments, Number Of Communities Managed

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Fair value portion of investments accounted under the equity method.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Acquisitions, Dispositions and Other Significant Transactions - Formation of Venture with Blackstone (Details) $ in Thousands		3 Months Ended				9 Months Ended
	Mar. 29, 2017 USD ($) community	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Business Acquisition [Line Items]
Payments to acquire joint venture						$ 8,946	$ 187,600
Goodwill and asset impairment		$ 5,500		$ 368,551		$ 451,966	390,816
Change in valuation allowance							86,600
HCP, Inc.
Business Acquisition [Line Items]
Term of lease	12 years
Formation of the Blackstone Venture
Business Acquisition [Line Items]
Change in valuation allowance					$ 85,000		$ 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
Percentage ownership	15.00%
Carrying value of investment	$ 66,800
Fair value of investment	$ 47,100
Goodwill and asset impairment			$ 33,400		$ 19,700
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