Present and Prospective Accounting Pronouncements Effect of change related to ASU 2016-18 (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash used in investing activities	$ (42.6)	$ (25.9)
Effect of exchange rate on cash, cash equivalents and restricted cash	1.2	0.7
Net decrease in cash, cash equivalents and restricted cash		(9.9)
Cash, cash equivalents and restricted cash at beginning of period	941.3	672.5
Cash, cash equivalents and restricted cash at end of period	$ 909.1	662.6
Scenario, Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash used in investing activities		(26.0)
Effect of exchange rate on cash, cash equivalents and restricted cash		0.9
Net decrease in cash, cash equivalents and restricted cash		(9.8)
Cash, cash equivalents and restricted cash at beginning of period		659.3
Cash, cash equivalents and restricted cash at end of period		649.5
Accounting Standards Update 2017-07 [Member] \| Scenario, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash used in investing activities		0.1
Effect of exchange rate on cash, cash equivalents and restricted cash		(0.2)
Net decrease in cash, cash equivalents and restricted cash		(0.1)
Cash, cash equivalents and restricted cash at beginning of period		13.2
Cash, cash equivalents and restricted cash at end of period		$ 13.1

Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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. Includes effect from exchange rate changes.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3044-108585

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 230
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

+ References

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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.

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