Goodwill and intangible assets - Schedule of goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 27, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	$ 3,897,452
Accumulated impairment losses, beginning balance	(1,327,425)
Goodwill, net, beginning balance	2,570,027
Goodwill recognized during the period	(9,642)
Currency translation during the period	(18,479)
Goodwill, gross, ending balance	3,869,331
Accumulated impairment losses, ending balance	(1,327,425)
Goodwill, net, ending balance	2,541,906
Global Ceramic segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	1,583,576
Accumulated impairment losses, beginning balance	(531,930)
Goodwill, net, beginning balance	1,051,646
Goodwill recognized during the period	0
Currency translation during the period	(16,538)
Goodwill, gross, ending balance	1,567,038
Accumulated impairment losses, ending balance	(531,930)
Goodwill, net, ending balance	1,035,108
Flooring NA segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	874,198
Accumulated impairment losses, beginning balance	(343,054)
Goodwill, net, beginning balance	531,144
Goodwill recognized during the period	0
Currency translation during the period	0
Goodwill, gross, ending balance	874,198
Accumulated impairment losses, ending balance	(343,054)
Goodwill, net, ending balance	531,144
Flooring ROW segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	1,439,678
Accumulated impairment losses, beginning balance	(452,441)
Goodwill, net, beginning balance	987,237
Goodwill recognized during the period	(9,642)
Currency translation during the period	(1,941)
Goodwill, gross, ending balance	1,428,095
Accumulated impairment losses, ending balance	(452,441)
Goodwill, net, ending balance	$ 975,654