Derivative Instruments and Hedging Activities - Schedule of Effects of Master Netting Agreements on Condensed Consolidated Balance Sheets (Detail) - Cash Flow Hedges [Member] - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	$ 46.7	$ 37.9
Offset	9.5	9.6
Net Amount in Balance Sheet	37.2	28.3
Other Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	20.1	20.9
Offset	3.1	3.5
Net Amount in Balance Sheet	17.0	17.4
Other Current Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	9.5	9.9
Offset	9.5	9.6
Net Amount in Balance Sheet		0.3
Other Long-term Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	3.1	3.7
Offset	$ 3.1	3.5
Net Amount in Balance Sheet		$ 0.2