Income Taxes (Additional Information) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) jurisdiction subsidiary	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Income Taxes [Line Items]
Effective income tax rate reconciliation, percent	25.60%	25.30%	23.60%
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	$ 327	$ 240
Undistributed earnings of foreign subsidiaries	$ 6,100
Number of PPG subsidiaries | subsidiary	245
Number of taxable jurisdictions | jurisdiction	65
Income tax, potential U.S. tax cost for repatriation of foreign earnings	$ 142
Unrecognized tax benefits that would affect the effective tax rate, if recognized	138
U.S.
Income Taxes [Line Items]
Income before income taxes of non-US operations	210	(129)	$ 290
Non United States
Income Taxes [Line Items]
Income before income taxes of non-US operations	$ 1,642	$ 1,819	$ 1,065