Income Taxes - Components of Deferred Taxes (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Inventory	$ 275.1us-gaap_DeferredTaxAssetsInventory	$ 271.1us-gaap_DeferredTaxAssetsInventory
Net operating loss carryover	116.9	26.4
Tax credit carryover	185.5	187.1
Capital loss carryover	7.4	7.8
Accrued liabilities	106.7	72.0
Share-based compensation	59.9	74.6
Unremitted earnings of foreign subsidiaries	32.3	25.6
Other	50.3us-gaap_DeferredTaxAssetsOther	11.2us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	834.1us-gaap_DeferredTaxAssetsGross	675.8us-gaap_DeferredTaxAssetsGross
Less: Valuation allowances	(122.8)	(42.7)
Total deferred tax assets after valuation	711.3us-gaap_DeferredTaxAssetsNet	633.1us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Fixed assets	(104.3)	(97.7)
Intangible assets	(95.9)	(106.4)
Other		(1.2)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	(200.2)us-gaap_DeferredIncomeTaxLiabilities	(205.3)us-gaap_DeferredIncomeTaxLiabilities
Total net deferred tax assets	$ 511.1us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 427.8us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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