Variable Interest Entities (Details)	6 Months Ended
Jun. 30, 2017 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	$ 50,700,000
Carrying Amount	$ 50,700,000
RIDEA Ventures [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures	10.00%
Number of joint ventures \| joint_venture	3
Maximum Exposure to Loss	$ 76,600,000
Carrying Amount	$ 76,600,000
Blackstone Venture [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures	15.00%
Number of communities managed \| community	60
Long term mortgage debt	$ 636,200,000
Number of communities leased \| community	2
Lease payments	$ 2,500,000
Fair market value of communities	33,800,000
Maximum Exposure to Loss	44,600,000
Carrying Amount	$ 44,600,000
HCP, Inc. [Member] \| CCRC Venture opco [Member]
Variable Interest Entity [Line Items]
Percentage ownership in unconsolidated joint ventures	49.00%
Mortgage Notes Payable [Member] \| Blackstone Venture [Member]
Variable Interest Entity [Line Items]
Mortgage debt payable	$ 66,800,000
Maximum amount to lend in case of refinancing short fall	$ 12,000,000.0

Debt Arrangement, Shortfall Amount, Maximum Amount To Lend

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- Definition

Equity Method Investments, Number Of Communities Managed

+ References

No definition available.

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- Definition

Number Of Joint Ventures

+ References

No definition available.

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- Definition

Operating Leases, Leasing Arrangement, Fair Market Value Of Communities

+ References

No definition available.

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- Definition

Operating Leases, Number Of Communities

+ References

No definition available.

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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

Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.12-29.6)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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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)
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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
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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.

+ References

No definition available.

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- Definition

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

No definition available.

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