Financial Instruments Financial Instruments - Foreign Currency Exchange Rate Risk and Concentration of Credit Risk (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Entity	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Derivative [Line Items]
Concentration Risk, Percentage	99.00%
Sales Revenue, Goods, Net [Member]
Derivative [Line Items]
Concentration Risk, Percentage	27.20%	26.70%	26.20%
Number of customers | Entity	3
Accounts Receivable [Member]
Derivative [Line Items]
Concentration Risk, Percentage	12.40%	12.90%
Accumulated Translation Adjustment [Member]
Derivative [Line Items]
Foreign currency gains of net investment hedges included in accumulated other comprehensive loss | $	$ 7.6	$ 26.6	$ 37.4