Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Indicates line item in statement of financial position that includes cash and cash equivalents restricted to withdrawal or usage, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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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.

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Indicates line item in statement of financial position that includes cash and cash equivalents restricted to withdrawal or usage, classified as noncurrent.

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Restricted Cash (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Restricted Cash
Current portion of restricted cash, balance sheet location	us-gaap:OtherAssetsCurrent
Non-current portion of restricted cash, balance sheet location	us-gaap:OtherAssetsNoncurrent
Cash and cash equivalents, including restricted cash	$ 302.6	$ 326.3	$ 287.8	$ 328.9
ASU 2016-18 - Restricted Cash
Restricted Cash
Cash and cash equivalents, including restricted cash	$ 3.8	$ 3.9	$ 3.9	$ 3.9