ACQUISITIONS - Schedule of Pro Forma Information (Details) - Environmental Stoneworks - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Apr. 29, 2018	Jun. 29, 2019	Apr. 29, 2018
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net sales	$ 1,295,457	$ 1,112,867	$ 2,376,385	$ 2,286,242
Net income (loss) applicable to common shares	$ 22,682	$ (58,308)	$ (18,200)	$ (162,686)
Net income (loss) per common share:
Basic (in dollars per share)	$ 0.18	$ (0.46)	$ (0.15)	$ (1.30)
Diluted (in dollars per share)	$ 0.18	$ (0.46)	$ (0.15)	$ (1.30)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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