Goodwill and intangible assets (Schedule of indefinite life assets not subject to amortization) (Details) - Tradenames [Member] $ in Thousands	6 Months Ended
Jul. 04, 2015 USD ($)
Indefinite-lived Intangible Assets [Roll Forward]
Indefinite life assets not subject to amortization, beginning balance	$ 622,691
Intangible assets acquired during the period	48,563
Currency translation during the year	(26,358)
Indefinite life assets not subject to amortization, ending balance	$ 644,896

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

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

- 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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Period Type:	duration

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

- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

+ References

No definition available.

+ Details

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

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