Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities
Net income attributable to the controlling and noncontrolling interests	$ 1,612	$ 899	$ 1,427
Income from discontinued operations, net of tax	220	330	95
Income from continuing operations	1,392	569	1,332
Adjustments to reconcile to cash from operations:
Depreciation and amortization	460	440	446
Defined benefit pension expense	65	85	88
Pension Settlement Charges	60	968	0
Business restructuring	0	195	136
Environmental remediation charge	0	82	0
Stock-based compensation expense	42	38	54
Gain (Loss) on Sale of Equity Investments	(25)	(39)	0
Equity affiliate (income)/loss, net of dividends	(4)	(6)	66
Deferred income taxes	36	174	0
Cash contributions to pension plans	(87)	(188)	(263)
Restructuring cash expenditures	(49)	(76)	(47)
Cash Paid for Asbestos Settlement Funding	0	(813)	0
Change in certain asset and liability accounts (net of acquisitions):
Receivables	(76)	(68)	(125)
Inventories	(116)	56	37
Other current assets	(43)	21	(81)
Accounts payable and accrued liabilities	186	169	152
Noncurrent assets and liabilities, net	(170)	(53)	79
Taxes and interest payable	(124)	(270)	(96)
Other	9	(66)	(19)
Cash from operating activities - continuing operations	1,556	1,218	1,759
Cash from operating activities - discontinued operations	12	133	136
Cash from operating activities	1,568	1,351	1,895
Investing activities
Additions to property and investments	(360)	(380)	(430)
Business acquisitions, net of cash balances acquired (See Note 2)	(225)	(349)	(320)
Payments to Acquire Equity Method Investments	(100)	0	0
Net proceeds from the sale of businesses	593	1,094	47
Proceeds from maturity of short-term investments	0	92	402
Purchase of short-term investments	(1)	0	(97)
Payments for the settlement of cross currency swap contracts	(34)	(36)	(34)
Proceeds from the settlement of cross currency swap contracts	37	37	37
(Payments on) / Proceeds from net investment hedges	0	(13)	19
Other	27	27	27
Cash (used for)/from investing activities - continuing operations	(63)	472	(349)
Cash used for investing activities - discontinued operations	(4)	(36)	(46)
Cash (used for)/from investing activities	(67)	436	(395)
Financing activities
Net change in borrowings with maturities of three months or less	(7)	(15)	(32)
Net payments on commercial paper and short-term debt	(93)	(361)	(528)
Proceeds from long term debt (net of discount and issuance costs) (See Note 8)	0	988	1,242
Repayment of long-term debt (See Note 8)	(588)	(379)	(340)
Payments Related to Tax Withholding for Share-based Compensation	(28)	(26)	(58)
Purchase of treasury stock	(813)	(1,050)	(751)
Issuance of treasury stock	52	31	53
Dividends paid on PPG common stock	(434)	(414)	(383)
Other	(43)	16	(15)
Cash used for financing activities	(1,954)	(1,210)	(812)
Effect of currency exchange rate changes on cash and cash equivalents	69	(68)	(63)
Net increase in cash and cash equivalents	(384)	509	625
Cash and cash equivalents, beginning of year	1,820	1,311	686
Cash and cash equivalents, end of year	1,436	1,820	1,311
Supplemental disclosures of cash flow information:
Interest paid, net of amount capitalized	100	118	115
Taxes paid, net of refunds	$ 648	$ 349	$ 383