Goodwill and intangible assets (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 28, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill	$ 1,730,713	$ 1,736,092
Laminate and Wood Segment [Member]
Goodwill [Line Items]
Enterprise value	303
Goodwill	810,096	808,210
Unidentified Wood Business [Member] \| Laminate and Wood Segment [Member]
Goodwill [Line Items]
Goodwill	$ 6,662

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

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