Debt - Summary of Debt Instruments (Detail) $ in Millions, ¥ in Billions	Mar. 31, 2018 USD ($)	Mar. 31, 2018 JPY (¥)	Mar. 19, 2018 USD ($)	Dec. 31, 2017 USD ($)
Current portion of long-term debt
Total current portion of long-term debt	$ 1,625.0			$ 1,225.0
Long-term debt
Senior Notes due	9,100.0
Other long-term debt	4.1			4.1
Debt discount and issuance costs	(55.3)			(53.2)
Adjustment related to interest rate swaps	21.0			23.1
Total long-term debt	9,486.9			8,917.5
Senior Notes [Member]
Long-term debt
Senior Notes due			$ 300.0
Senior Notes [Member] | 2.0% [Member] | Due in 2018 [Member]
Current portion of long-term debt
Total current portion of long-term debt	1,150.0			1,150.0
Senior Notes [Member] | 4.625% [Member] | Due in 2019 [Member]
Long-term debt
Senior Notes due	500.0			500.0
Senior Notes [Member] | 2.7% [Member] | Due in 2020 [Member]
Long-term debt
Senior Notes due	1,500.0			1,500.0
Senior Notes [Member] | 3.375% [Member] | Due in 2021 [Member]
Long-term debt
Senior Notes due	300.0			300.0
Senior Notes [Member] | 3.150% [Member] | Due in 2022 [Member]
Long-term debt
Senior Notes due	750.0			750.0
Senior Notes [Member] | 3.7% [Member] | Due in 2023 [Member]
Long-term debt
Senior Notes due	300.0
Senior Notes [Member] | 3.550% [Member] | Due in 2025 [Member]
Long-term debt
Senior Notes due	2,000.0			2,000.0
Senior Notes [Member] | 4.250% [Member] | Due in 2035 [Member]
Long-term debt
Senior Notes due	253.4			253.4
Senior Notes [Member] | 5.750% [Member] | Due in 2039 [Member]
Long-term debt
Senior Notes due	317.8			317.8
Senior Notes [Member] | 4.450% [Member] | Due in 2045 [Member]
Long-term debt
Senior Notes due	395.4			395.4
Multicurrency Revolving Facility [Member]
Current portion of long-term debt
Total current portion of long-term debt	400.0
Floating Rate Notes [Member]
Long-term debt
Senior Notes due			$ 450.0
Floating Rate Notes [Member] | Due in 2021 [Member]
Long-term debt
Senior Notes due	450.0
Euro Notes [Member]
Long-term debt
Term loan	1,200.0
Euro Notes [Member] | 1.414% [Member] | Due in 2022 [Member]
Long-term debt
Term loan	614.9			600.4
Euro Notes [Member] | 2.425% [Member] | Due in 2026 [Member]
Long-term debt
Term loan	614.9			600.4
U.S. Term Loan A [Member]
Long-term debt
Term loan	610.0			835.0
U.S. Term Loan B [Member]
Current portion of long-term debt
Total current portion of long-term debt	75.0			75.0
Long-term debt
Term loan	600.0			600.0
Japan Term Loan A [Member]
Long-term debt
Term loan	110.2	¥ 11.7		103.2
Japan Term Loan B [Member]
Long-term debt
Term loan	$ 200.5	¥ 21.3		$ 187.9