Revenue - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Monthly resident fees	$ 58.3	$ 58.3	$ 49.7
Revenue recognized		68.9
Additions for allowance for doubtful accounts	4.4	8.9
Deferred Revenue and Credits
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 115.6	$ 115.6	$ 112.4

Contract With Customer, Liability, Deferred Revenue

No definition available.

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- Definition

Contract With Customer, Liability, Deferred Revenue, Monthly Resident Fees

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in the allowance for doubtful accounts.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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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.

+ Details

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