Equity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 25, 2015	Sep. 26, 2014	Sep. 25, 2015	Sep. 26, 2014
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ (100,736)
Ending balance	$ (100,499)		(100,499)
Pension and Post-retirement Medical
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(73,868)	$ (48,583)	(76,584)	$ (50,132)
Other comprehensive income before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income	1,700	973	4,416	2,522
Ending balance	(72,168)	(47,610)	(72,168)	(47,610)
Reclassification from AOCI
Reclassification before tax	2,537	1,463	6,894	3,876
Income tax (benefit)	(837)	(490)	(2,478)	(1,354)
Reclassification after tax	1,700	973	4,416	2,522
Cumulative Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(14,759)	1,789	(24,152)	3,783
Other comprehensive income before reclassifications	(13,572)	(12,888)	(4,179)	(14,882)
Amounts reclassified from accumulated other comprehensive income	0	0	0	0
Ending balance	(28,331)	(11,099)	(28,331)	(11,099)
Reclassification from AOCI
Reclassification after tax	0	0	0	0
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(88,627)	(46,794)	(100,736)	(46,349)
Other comprehensive income before reclassifications	(13,572)	(12,888)	(4,179)	(14,882)
Amounts reclassified from accumulated other comprehensive income	1,700	973	4,416	2,522
Ending balance	(100,499)	(58,709)	(100,499)	(58,709)
Reclassification from AOCI
Reclassification after tax	1,700	973	4,416	2,522
Cost of products sold \| Pension and Post-retirement Medical
Reclassification from AOCI
Reclassification before tax	959	536	2,604	1,412
Product development \| Pension and Post-retirement Medical
Reclassification from AOCI
Reclassification before tax	418	234	1,120	616
Selling, marketing and distribution \| Pension and Post-retirement Medical
Reclassification from AOCI
Reclassification before tax	718	427	1,950	1,116
General and administrative \| Pension and Post-retirement Medical
Reclassification from AOCI
Reclassification before tax	$ 442	$ 266	$ 1,220	$ 732

Tax effect of reclassification adjustments of other comprehensive income (loss).

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: 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=36458714&loc=d3e637-108580

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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