Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 35
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82918529&loc=d3e30304-110892

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (b,d)
-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32211-110900

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Name:	us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Financial Instruments Financial Instruments - Foreign Currency Exchange Rate Risk and Concentration of Credit Risk (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) Entity	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Derivative [Line Items]
Concentration Risk, Percentage	99.00%
Sales Revenue, Goods, Net [Member]
Derivative [Line Items]
Concentration Risk, Percentage	23.70%	27.20%	26.70%
Number of customers \| Entity	3
Accounts Receivable [Member]
Derivative [Line Items]
Concentration Risk, Percentage	6.20%	12.40%
Accumulated Translation Adjustment [Member]
Derivative [Line Items]
Foreign currency (losses) gains of net investment hedges included in accumulated other comprehensive loss \| $	$ (46.1)	$ 7.6	$ 26.6