Goodwill and intangible assets - Schedule of goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	$ 3,601,851
Accumulated impairment losses	(1,327,425)
Goodwill, net, beginning balance	2,274,426
Goodwill recognized or adjusted during the period	60,493
Currency translation during the period	119,441
Goodwill, gross, ending balance	3,781,785
Accumulated impairment losses	(1,327,425)
Goodwill, net, ending balance	2,454,360
Operating segments | Global Ceramic segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	1,482,226
Accumulated impairment losses	(531,930)
Goodwill, net, beginning balance	950,296
Goodwill recognized or adjusted during the period	60,493
Currency translation during the period	21,952
Goodwill, gross, ending balance	1,564,671
Accumulated impairment losses	(531,930)
Goodwill, net, ending balance	1,032,741
Operating segments | Flooring NA segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	869,764
Accumulated impairment losses	(343,054)
Goodwill, net, beginning balance	526,710
Goodwill recognized or adjusted during the period	0
Currency translation during the period	0
Goodwill, gross, ending balance	869,764
Accumulated impairment losses	(343,054)
Goodwill, net, ending balance	526,710
Operating segments | Flooring ROW segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	1,249,861
Accumulated impairment losses	(452,441)
Goodwill, net, beginning balance	797,420
Goodwill recognized or adjusted during the period	0
Currency translation during the period	97,489
Goodwill, gross, ending balance	1,347,350
Accumulated impairment losses	(452,441)
Goodwill, net, ending balance	$ 894,909