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Effect of New Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 01, 2016 | Sep. 30, 2018 | Sep. 30, 2017 | [1] | Sep. 30, 2018 | Sep. 30, 2017 | [1] | Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Corporate income tax rate |  |  |  | 21.00% |  | 35.00%
Benefit for income taxes |  | $ (48.1) | $ (41.2) | $ (111.9) | $ (107.8) |
Net cash provided by operating activities |  |  |  | 504.6 | 593.2 |
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash |  |  |  | (52.1) | $ 98.5 |
Accounting Standards Update 2016-18 [Member] |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Net cash provided by operating activities |  |  |  | 134.1 |  |
Cash paid for acquisitions, net of cash and restricted cash |  |  |  | 17.8 |  |
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash |  |  |  | 71.6 |  |
Accounting Standards Update 2014-09 [Member] |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Cumulative effect of adoption recognized as an increase to retained earnings | $ 125.3 |  |  |  |  |
Accounting Standards Update 2018-02 [Member] |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Increase in retained earnings |  |  |  | $ 6.6 |  |
Accounting Standards Update 2018-05 [Member] |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Benefit for income taxes |  | $ 4.7 |  |  |  |
[1] | See Note 3 - Revenues from Contracts with Customers for additional information about the restatements related to Topic 606.

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- Definition Amount of increase (decrease) from effect of exchange rate changes on cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; held in foreign currencies. Excludes amounts 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/disclosureRef -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 + Details
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