GOODWILL (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 03, 2021	Apr. 04, 2020
Goodwill [Roll Forward]
Beginning balance	$ 1,194,729	$ 1,669,594
Goodwill recognized from acquisition	122	12,539
Impairment	0	(503,171)
Currency translation	1,132	13,991
Purchase accounting adjustments		1,776
Ending balance	1,195,983
Windows
Goodwill [Roll Forward]
Beginning balance	397,024	714,023
Goodwill recognized from acquisition	0	0
Impairment		(320,990)
Currency translation	648	3,991
Purchase accounting adjustments		0
Ending balance	397,672
Siding
Goodwill [Roll Forward]
Beginning balance	654,821	807,280
Goodwill recognized from acquisition	122	12,539
Impairment		(176,774)
Currency translation	484	10,000
Purchase accounting adjustments		1,776
Ending balance	655,427
Commercial
Goodwill [Roll Forward]
Beginning balance	142,884	148,291
Goodwill recognized from acquisition	0	0
Impairment		(5,407)
Currency translation	0	0
Purchase accounting adjustments		$ 0
Ending balance	$ 142,884

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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