Condensed Consolidated Statement of Shareholders' Equity (Unaudited) Statement - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss	Total PPG	Non-controlling Interests
Beginning balance at Dec. 31, 2022	$ 6,709	$ 969	$ 1,130	$ 20,828	$ (13,525)	$ (2,810)	$ 6,592	$ 117
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	273			264			264	9
Other comprehensive loss, net of tax	403					402	402	1
Cash dividends	(146)			(146)			(146)
Issuance of treasury stock	31		21		10		31
Stock-based compensation activity	(1)		(1)				(1)
Dividends paid on subsidiary common stock to noncontrolling interests	(1)							(1)
Reductions in noncontrolling interests	(15)							(15)
Ending balance at Mar. 31, 2023	7,253	969	1,150	20,946	(13,515)	(2,408)	7,142	111
Beginning balance at Dec. 31, 2022	6,709	969	1,130	20,828	(13,525)	(2,810)	6,592	117
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	1,206
Other comprehensive loss, net of tax	337
Ending balance at Sep. 30, 2023	7,935	969	1,193	21,563	(13,502)	(2,472)	7,751	184
Beginning balance at Mar. 31, 2023	7,253	969	1,150	20,946	(13,515)	(2,408)	7,142	111
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	497			490			490	7
Other comprehensive loss, net of tax	109					109	109
Cash dividends	(146)			(146)			(146)
Issuance of treasury stock	10		7		3		10
Stock-based compensation activity	9		9				9
Dividends paid on subsidiary common stock to noncontrolling interests	(10)							(10)
Reductions in noncontrolling interests	70							70
Ending balance at Jun. 30, 2023	7,792	969	1,166	21,290	(13,512)	(2,299)	7,614	178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	436			426			426	10
Other comprehensive loss, net of tax	(175)					(173)	(173)	(2)
Cash dividends	(153)			(153)			(153)
Issuance of treasury stock	28		18		10		28
Stock-based compensation activity	9		9				9
Dividends paid on subsidiary common stock to noncontrolling interests	(2)							(2)
Ending balance at Sep. 30, 2023	7,935	969	1,193	21,563	(13,502)	(2,472)	7,751	184
Beginning balance at Dec. 31, 2023	8,023	969	1,202	21,500	(13,600)	(2,239)	7,832	191
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	409			400			400	9
Other comprehensive loss, net of tax	(14)					(12)	(12)	(2)
Cash dividends	(153)			(153)			(153)
Purchase of treasury stock	(152)				(152)		(152)
Issuance of treasury stock	37		31		6		37
Stock-based compensation activity	(11)		(11)				(11)
Dividends paid on subsidiary common stock to noncontrolling interests	(2)							2
Reductions in noncontrolling interests	(11)							(11)
Ending balance at Mar. 31, 2024	8,126	969	1,222	21,747	(13,746)	(2,251)	7,941	185
Beginning balance at Dec. 31, 2023	8,023	969	1,202	21,500	(13,600)	(2,239)	7,832	191
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	1,420
Other comprehensive loss, net of tax	(544)
Ending balance at Sep. 30, 2024	7,972	969	1,258	22,432	(14,091)	(2,780)	7,788	184
Beginning balance at Mar. 31, 2024	8,126	969	1,222	21,747	(13,746)	(2,251)	7,941	185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	537			528			528	9
Other comprehensive loss, net of tax	(414)					(412)	(412)	(2)
Cash dividends	(152)			(152)			(152)
Purchase of treasury stock	(152)				(152)		(152)
Issuance of treasury stock	4		3		1		4
Stock-based compensation activity	10		10				10
Dividends paid on subsidiary common stock to noncontrolling interests	(13)							(13)
Other	(1)							(1)
Ending balance at Jun. 30, 2024	7,945	969	1,235	22,123	(13,897)	(2,663)	7,767	178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	474			468			468	6
Other comprehensive loss, net of tax	(116)					(117)	(117)	1
Cash dividends	(159)			(159)			(159)
Purchase of treasury stock	(202)				(202)		(202)
Issuance of treasury stock	19		11		8		19
Stock-based compensation activity	12		12				12
Dividends paid on subsidiary common stock to noncontrolling interests	(1)							(1)
Ending balance at Sep. 30, 2024	$ 7,972	$ 969	$ 1,258	$ 22,432	$ (14,091)	$ (2,780)	$ 7,788	$ 184