Restructuring - Summary of Restructuring Activities (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 50.2	$ 44.3	$ 44.2
Charges	81.1	107.0	75.4
Utilization, Cash	(53.6)	(100.6)	(66.1)
Utilization, Non-cash	(5.9)	(0.5)	(9.2)
Accrual as of end of period	71.8	50.2	44.3
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	45.1	38.7	38.5
Charges	70.0	88.6	54.1
Utilization, Cash	(48.6)	(82.2)	(53.9)
Utilization, Non-cash	0.0	0.0	0.0
Accrual as of end of period	66.5	45.1	38.7
Asset impairments
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0	0.0	0.0
Charges	3.9	0.5	9.2
Utilization, Cash	0.0	0.0	0.0
Utilization, Non-cash	(3.9)	(0.5)	(9.2)
Accrual as of end of period	0.0	0.0	0.0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	5.1	5.6	5.7
Charges	1.7	0.5	0.3
Utilization, Cash	(1.5)	(1.0)	(0.4)
Utilization, Non-cash	0.0	0.0	0.0
Accrual as of end of period	5.3	5.1	5.6
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0	0.0	0.0
Charges	5.5	17.4	11.8
Utilization, Cash	(3.5)	(17.4)	(11.8)
Utilization, Non-cash	(2.0)	0.0	0.0
Accrual as of end of period	$ 0.0	$ 0.0	$ 0.0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of consideration other than cash used to fully or partially settle an accrued restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
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