Long-Term and Other Debt - Gain (Loss) on Debt Financing Transactions (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Feb. 28, 2018	Aug. 31, 2017	Feb. 28, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Repurchase and cancellation of principal balance at premium (discount)				$ 110.3	$ 0.0	$ (26.0)
Unamortized debt (premium) discount and deferred financing costs. net				(29.8)	26.4	0.8
Third party debt issuance fees				12.7	11.7	0.0
Loss (gain) on debt financing transactions	$ 93.2	$ 8.4	$ 29.7	$ 93.2	$ 38.1	$ (25.2)

Repurchase And Cancellation Of Principal Balance At Premium (Discount)

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- Definition

Write Off Of Deferred Debt Issuance Costs And Discount (Premium)

+ References

No definition available.

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- References

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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