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	Jun. 30, 2019	Dec. 31, 2018
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	$ 42.0	$ 37.9
Offset	8.3	9.6
Net Amount in Balance Sheet	33.7	28.3
Other Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	12.5	20.9
Offset	3.5	3.5
Net Amount in Balance Sheet	9.0	17.4
Other Current Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	8.5	9.9
Offset	8.3	9.6
Net Amount in Balance Sheet	0.2	0.3
Other Long-term Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	3.9	3.7
Offset	3.5	3.5
Net Amount in Balance Sheet	$ 0.4	$ 0.2