Variable Interest Entities (Details) $ in Millions		3 Months Ended
Mar. 29, 2017 community	Mar. 31, 2018 USD ($) community joint_venture
CCRC Venture opco [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures		51.00%
Maximum Exposure to Loss		$ 31.3
Carrying Amount		$ 31.3
RIDEA Ventures [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures		10.00%
Number of joint ventures \| joint_venture		1
Maximum Exposure to Loss		$ 20.6
Carrying Amount		$ 20.6
Blackstone Venture [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures		15.00%
Number of communities managed \| community	60
Number of communities leased \| community	2	2
Lease payments		$ 2.6
Fair market value of communities		$ 33.8
HCP, Inc. [Member] \| CCRC Venture opco [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures		49.00%

Equity Method Investments, Number Of Communities Managed

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Number Of Joint Ventures

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- Definition

Operating Leases, Leasing Arrangement, Fair Market Value Of Communities

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Operating Leases, Number Of Communities

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5747-111685

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- Definition

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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Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

+ References

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