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Effect of New Accounting Pronouncements - Additional Information (Detail) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Income tax benefit recognized |  | $ (121,100,000) | $ (88,100,000) | $ (95,600,000)
Reclassification of payments from investing activities to operating activities |  | 854,200,000 | 649,600,000 | 686,100,000
Reclassification of payments from investing activities to financing activities |  | (47,800,000) | (11,600,000) | (31,700,000)
Cash paid for acquisitions, net of cash and restricted cash |  | 376,100,000 | 243,400,000 | 249,600,000
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash |  | $ 72,000,000 | (107,600,000) | (75,000,000)
Description of contracts renewal period |  | One year or less |  |
Minimum [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Cumulative effect on retained earnings | $ 100,000,000 |  |  |
Maximum [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Cumulative effect on retained earnings | $ 180,000,000 |  |  |
Restatement Adjustment [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Reclassification of payments from investing activities to operating activities |  |  | 22,800,000 | 12,100,000
Reclassification of payments from investing activities to financing activities |  |  | 45,500,000 | 21,800,000
Accounting Standards Update 2016-09 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Income tax benefit recognized |  | $ 15,100,000 | 6,500,000 | 5,300,000
Accounting Standards Update 2016-18 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Net cash provided by operating activities |  |  | 50,300,000 | 45,600,000
Cash paid for acquisitions, net of cash and restricted cash |  |  | 15,600,000 | 58,800,000
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash |  |  | $ 85,900,000 | $ 59,900,000

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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/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 830 -SubTopic 230 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906 + Details
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