Segment reporting (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2016 USD ($)	Jul. 04, 2015 USD ($)	Jul. 02, 2016 USD ($) segment	Jul. 04, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment			3
Segment Reporting Information [Line Items]
Net sales	$ 2,310,336	$ 2,041,733	$ 4,482,382	$ 3,922,910
Operating income (loss)	350,692	255,816	596,364	299,590
Assets	10,312,831		10,312,831		$ 9,934,400
Operating Segments [Member] | Global Ceramic Segment [Member]
Segment Reporting Information [Line Items]
Net sales	829,794	789,802	1,603,520	1,509,630
Operating income (loss)	140,606	121,189	240,383	206,516
Assets	4,054,351		4,054,351		3,846,133
Operating Segments [Member] | Flooring NA Segment [Member]
Segment Reporting Information [Line Items]
Net sales	980,693	920,337	1,887,057	1,767,248
Operating income (loss)	118,946	95,143	194,297	19,951
Assets	3,316,048		3,316,048		3,164,525
Operating Segments [Member] | Flooring ROW Segment [Member]
Segment Reporting Information [Line Items]
Net sales	499,849	331,622	991,805	646,364
Operating income (loss)	101,062	53,052	180,599	97,693
Assets	2,835,497		2,835,497		2,805,246
Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	0	(28)	0	(332)
Corporate And Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	(9,922)	$ (13,568)	(18,915)	$ (24,570)
Assets	$ 106,935		$ 106,935		$ 118,496