Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Estimated period for the anticipated transfer of gain (loss), net, from accumulated other comprehensive income into earnings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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Derivative Financial Instruments - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2016 EUR (€)	Dec. 30, 2016 EUR (€)	Dec. 31, 2015 EUR (€)
Foreign Currency Exchange Contracts [Member]
Derivatives Fair Value [Line Items]
Notional amounts on foreign currency exchange contracts \| €		€ 0	€ 9,100,000	€ 0
Research and development [Member]
Derivatives Fair Value [Line Items]
Gain (loss) reclassification from accumulated other comprehensive income	12 months
Other Income (Expense) [Member]
Derivatives Fair Value [Line Items]
Gain (loss) on discontinuance of cash flow hedges \| $	$ 0
Maximum [Member]
Derivatives Fair Value [Line Items]
Derivative instruments maturity term	12 months