Summary of Significant Accounting Policies - Schedule of Future Minimum Payments to be Received (Details) $ in Millions	Dec. 31, 2017 USD ($)
Accounting Policies [Abstract]
Total	$ 1,026.9
Less than 1 year	106.3
Years 2 to 3	212.6
Years 4 to 5	212.6
More than 5 years	$ 495.4

Operating Leases, Future Minimum Payments Receivable, In Four And Five Years

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- Definition

Operating Leases, Future Minimum Payments Receivable, In Two And Three Years

+ References

No definition available.

+ Details

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- Definition

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

+ Details

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

+ References

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