Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts	$ 4.4	$ 3.8
Liability related to prepaid rental payments	19.8	16.7
Straight line rent receivable	53.8	$ 53.9
Difference between Revenue Guidance in Effect before and after Topic 606 \| Accounting Standards Update 2014-09
Summary Of Significant Accounting Policies [Line Items]
Retained earnings	$ 2.3

[Line Items] for Summary Of Significant Accounting Policies [Table]

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Amount at the balance sheet date that has been received by the entity that represents rents paid in advance.

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For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable is reduced by allowances attributable to, for instance, credit risk associated with a lessee.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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