The effective portion of gain reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of losses on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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Derivative and Hedging Activities gain losses in Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2017	Sep. 30, 2016	Sep. 29, 2017	Sep. 30, 2016
Derivatives, Fair Value [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ 0		$ 0	$ (53)
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		$ 47
Other Comprehensive Income (Loss) [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion	0	121	0	279
Cost of Sales [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	0		0	(7)
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		6
Operating Expense [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	0		0	(46)
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		41
Other Nonoperating Income (Expense) [Member]
Derivatives, Fair Value [Line Items]
Losses recognized in income on derivatives (ineffectiveness portion and amount excluded from effectiveness testing)	0	(8)	0	(57)
Other Nonoperating Income (Expense) [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Gains (losses) recognized in income	$ 119	$ (162)	$ (66)	$ (496)