Contingencies - Additional Information (Detail) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021 USD ($) Project	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Environmental remediation reserve balance, current	$ 33		$ 29
Liabilities incurred	4	$ 2	7
Payments related to remediation expenses applied against the reserve	5	3	19
Reversals of previously recorded liabilities	7
Decrease in reserves due to effects of foreign currency translation		$ 6
Active or future remediation for significant sites	254		259
Accrued environmental reserves	$ 311		322	$ 335
Massena, New York [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Environmental remediation work completion period	4 years
Massena, New York [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Environmental remediation work completion period	8 years
Sherwin, Texas [Member]
Loss Contingencies [Line Items]
Beginning of expected term for reuse of residue bed	8 years
Ending of expected term for reuse of residue bed	10 years
Other Sites [Member]
Loss Contingencies [Line Items]
Number of remediation projects | Project	35
Accrued environmental reserves	$ 57		$ 63