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, 2021	$ 6,411	$ 969	$ 1,081	$ 20,372	$ (13,386)	$ (2,750)	$ 6,286	$ 125
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	23			18			18	5
Other comprehensive loss, net of tax	33					36	36	(3)
Cash dividends	(139)			(139)			(139)
Issuance of treasury stock	29		24		5		29
Stock-based compensation activity	(12)		(12)				(12)
Dividends paid on subsidiary common stock to noncontrolling interests	(1)							(1)
Reductions in noncontrolling interests	(11)							(11)
Ending balance at Mar. 31, 2022	6,333	969	1,093	20,251	(13,381)	(2,714)	6,218	115
Beginning balance at Dec. 31, 2021	6,411	969	1,081	20,372	(13,386)	(2,750)	6,286	125
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	808
Other comprehensive loss, net of tax	(532)
Ending balance at Sep. 30, 2022	6,144	969	1,122	20,736	(13,527)	(3,266)	6,034	110
Beginning balance at Mar. 31, 2022	6,333	969	1,093	20,251	(13,381)	(2,714)	6,218	115
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	446			441			441	5
Other comprehensive loss, net of tax	(214)					(208)	(208)	(6)
Cash dividends	(140)			(140)			(140)
Treasury Stock, Value, Acquired, Cost Method	150				150		150
Issuance of treasury stock	9		6		3		9
Stock-based compensation activity	9		9				9
Dividends paid on subsidiary common stock to noncontrolling interests	(6)							(6)
Stockholders' Equity, Other	4		3				3	1
Ending balance at Jun. 30, 2022	6,291	969	1,111	20,552	(13,528)	(2,922)	6,182	109
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	339			329			329	10
Other comprehensive loss, net of tax	(351)					(344)	(344)	(7)
Cash dividends	(145)			(145)			(145)
Issuance of treasury stock	3		2		1		3
Stock-based compensation activity	9		9				9
Dividends paid on subsidiary common stock to noncontrolling interests	(1)							(1)
Stockholders' Equity, Other	(1)							(1)
Ending balance at Sep. 30, 2022	6,144	969	1,122	20,736	(13,527)	(3,266)	6,034	110
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)
Acquisition of 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