RESTRUCTURING AND ACQUISITION-RELATED COSTS RESTRUCTURING (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1	$ 5	$ 2	$ 10
Restructuring cost, expected cost	3		3
2020 Insulation Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Restructuring costs			2
Restructuring reserve	1		1		$ 2
Payments			(1)
Accelerated depreciation and other non-cash items			2
Cumulative charges incurred	25		25
2020 Composites Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Restructuring costs			0
Restructuring reserve	0		0		2
Payments			(2)
Accelerated depreciation and other non-cash items			0
Cumulative charges incurred	13		13
Pittsburgh Corning Related Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring costs			(1)
Restructuring reserve	6		6		$ 9
Payments			(2)
Accelerated depreciation and other non-cash items			0
Cumulative charges incurred	28		28
Accelerated depreciation
Restructuring Cost and Reserve [Line Items]
Restructuring costs			2
Accelerated depreciation | Cost Reductions Actions 2017 | Cost of sales
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Accelerated Depreciation	1	0	2	1
Other exit costs | Cost Reductions Actions 2017 | Cost of sales
Restructuring Cost and Reserve [Line Items]
Restructuring costs	0	1	0	3
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	7		7
Restructuring reserve, noncurrent	2		2
Restructuring reserve, current	5		5
Severance | Cost Reductions Actions 2017 | Other (income) expenses, net
Restructuring Cost and Reserve [Line Items]
Restructuring costs	(2)	3	(2)	5
Other exit costs | Cost Reductions Actions 2017 | Marketing and administrative expenses
Restructuring Cost and Reserve [Line Items]
Restructuring costs	1	0	1	0
Other exit costs | Cost Reductions Actions 2017 | Other (income) expenses, net
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1	$ 1	$ 1	$ 1