Gains (Losses) Recognized in AOCI and Reclassified from AOCI on Derivatives (Effective Portion) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	$ (3.8)	$ (16.5)
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	0.9	1.4
Net Investment Hedging [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	(3.6)	(17.7)
Net Investment Hedging [Member] \| Foreign Exchange Contract [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)		(4.6)
Net Investment Hedging [Member] \| Long Term Debt [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	(3.6)	(13.1)
Cash Flow Hedging [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	(0.2)	1.2
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	0.9	1.4
Cash Flow Hedging [Member] \| Treasury Rate Lock [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	(0.1)
Cash Flow Hedging [Member] \| Cross-Currency Swap [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	(0.2)	1.2
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	1.0	1.4
Cash Flow Hedging [Member] \| Cross-Currency Swap [Member] \| Other Nonoperating Income (Expense) [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	$ 1.5	$ 2.2

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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