Goodwill and intangible assets - Schedule of indefinite life assets not subject to amortization (Details) - USD ($) $ in Thousands	9 Months Ended
Oct. 01, 2016	Oct. 03, 2015
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets impaired during the period	$ (47,905)	$ 0
Tradenames [Member]
Indefinite-lived Intangible Assets [Roll Forward]
Indefinite life assets not subject to amortization, beginning balance	632,349
Intangible assets impaired during the period	(47,905)
Currency translation during the period	14,751
Indefinite life assets not subject to amortization, ending balance	$ 599,195

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit, from foreign currency translation and purchase accounting adjustments.

+ References

No definition available.

+ Details

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