PPG Industries (PPG) 10-K/A 28 Jun 18 2017 FY Annual report (amended) Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Jan. 31, 2018	Jun. 30, 2017
Document Documentand Entity Information [Abstract]
Document Type	10-K/A
Amendment Flag	true
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	PPG
Entity Registrant Name	PPG INDUSTRIES INC
Entity Central Index Key	79,879
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		249,880,613
Entity Public Float			$ 28,173
Amendment Description	PPG is filing this Amendment No. 1 (this “Form 10-K/A”) to amend our Annual Report on Form 10-K for the year ended December 31, 2017 filed with the Securities and Exchange Commission (the “SEC”) on February 15, 2018 (the “Original Filing”) to restate our audited consolidated financial statements for the years ended December 31, 2017 and 2016 and to amend related disclosures, including those regarding our disclosure controls and procedures. We have also restated certain unaudited quarterly results related to the quarters ended December 31, 2016, March 31, 2017, June 30, 2017, September 30, 2017 and December 31, 2017. This Form 10-K/A also amends certain other items in the Original Filing, as listed in “Items Amended in this Filing” in the Explanatory Note.

Consolidated Statement of Incom

Consolidated Statement of Income - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	2,119	2,101	2,082	1,905	1,910	1,978	1,988	1,817	3,987		6,088		8,207	7,693	7,786
Selling, general and administrative	908	902	872	882	868	893	930	897	1,754		2,656		3,564	3,588	3,584
Depreciation	86	85	81	79	79	82	79	79	160		245		331	319	314
Amortization	34	32	32	31	30	31	30	30	63		95		129	121	132
Research and development, net	116	114	113	110	115	115	115	114	223		337		453	459	466
Interest expense	27	27	26	25	29	34	31	31	51		78		105	125	125
Interest income	(7)	(5)	(4)	(4)	(6)	(6)	(7)	(7)	(8)		(13)		(20)	(26)	(39)
Asbestos settlement, net					0	0	2	3					0	5	12
Business restructuring					191	0	0	0					0	191	136
Pension settlement charges	38	0	0	22	0	968	0	0	22	$ 0	22	$ 968	60	968	0
Other charges	25	13	12	14	117	12	29	17	26		39		64	175	90
Other income	(41)	(16)	(69)	(24)	(47)	(21)	(45)	(14)	(93)		(109)		(150)	(127)	(110)
Income before income taxes	377	523	659	446	131	(426)	630	444	1,105	$ 1,074	1,628	$ 648	2,005	779	1,745
Income tax expense	224	124	157	110	40	(220)	285	109	267		391		615	214	413
Income from continuing operations	153	399	502	336	91	(206)	345	335	838		1,237		1,390	565	1,332
Income from discontinued operations, net of tax	3	217	(1)	6	253	27	31	19	5		222		225	330	95
Net income attributable to the controlling and noncontrolling interests	156	616	501	342	344	(179)	376	354	843		1,459		1,615	895	1,427
Less: net income attributable to noncontrolling interests	5	6	5	5	4	5	6	7	10		16		21	22	21
Net income (attributable to PPG)	151	610	496	337	340	(184)	370	347	833		1,443		1,594	873	1,406
Continuing operations	148	393	497	331	87	(211)	339	328	828		1,221		1,369	543	1,311
Discontinued operations	$ 3	$ 217	$ (1)	$ 6	$ 253	$ 27	$ 31	$ 19	$ 5		$ 222		$ 225	$ 330	$ 95
Earnings per common share
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22		$ 4.75		$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.88	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24		5.61		6.22	3.29	5.18
Earnings per common share - assuming dilution
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19		4.72		5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.87	1.23	0.35
Net Income (attributable to PPG) (in dollars per share)	$ 0.59	$ 2.36	$ 1.92	$ 1.30	$ 1.29	$ (0.69)	$ 1.37	$ 1.29	$ 3.21		$ 5.58		$ 6.18	$ 3.27	$ 5.14

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 156	$ 616	$ 501	$ 342	$ 344	$ (179)	$ 376	$ 354	$ 843	$ 1,459	$ 1,615	$ 895	$ 1,427
Unrealized foreign currency translation gains/(losses)		(29)	(55)	21					(34)	(63)	248	(476)	(717)
Defined benefit pension and other postretirement benefit adjustments		26	82	279					361	387	78	808	113
Unrealized (losses)/gains – derivative financial instruments		1	(4)	(13)					(17)	(16)	(10)	4	5
Other comprehensive income/(loss), net of tax		(2)	23	287					310	308	316	336	(599)
Total comprehensive income		614	524	629					1,153	1,767	1,931	1,231	828
Less: amounts attributable to noncontrolling interests:
Net income	$ (5)	(6)	(5)	(5)	$ (4)	$ (5)	$ (6)	$ (7)	(10)	(16)	(21)	(22)	(21)
Unrealized foreign currency translation (losses)/gains		(2)	(6)	(7)					(13)	(15)	(17)	10	13
Comprehensive income attributable to PPG		$ 606	$ 513	$ 617					$ 1,130	$ 1,736	$ 1,893	$ 1,219	$ 820

Consolidated Balance Sheet

Consolidated Balance Sheet - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 1,436	$ 2,287	$ 1,569	$ 1,349	$ 1,820	$ 1,311	$ 686
Short-term investments	55	41	48	40	43
Receivables	2,903	3,155	3,191	3,013	2,654
Inventories	1,730	1,805	1,766	1,699	1,514
Assets held-for-sale	0	0	177	223	223
Other	353	350	390	439	320
Total current assets	6,477	7,638	7,141	6,763	6,574
Property, plant and equipment, net	2,824	2,730	2,710	2,659	2,608	2,608
Goodwill	3,942	3,881	3,845	3,720	3,572	3,625
Identifiable intangible assets, net	2,045	2,099	2,118	2,080	1,983
Deferred income taxes	305	422	321	170	186
Investments	268	261	256	175	179
Other assets	677	585	582	587	669
Total	16,538	17,616	16,973	16,154	15,771
Current liabilities
Accounts payable and accrued liabilities	3,781	3,900	3,656	3,517	3,460
Restructuring reserves	102	107	115	95	100
Short-term debt and current portion of long-term debt	12	616	619	604	629
Liabilities held-for-sale	0	0	54	69	64
Total current liabilities	3,895	4,623	4,444	4,285	4,253
Long-term debt	4,134	4,089	3,998	3,817	3,787
Accrued pensions	729	759	748	712	740
Other postretirement benefits	699	767	755	720	724
Deferred income taxes	442				417
Other liabilities	967	928	910	934	935
Total liabilities	10,866	11,611	11,245	10,868	10,856
Commitments and contingent liabilities (See Note 14)
Shareholders’ equity
Common stock	969	969	969	969	969
Additional paid-in capital	756	745	723	711	707
Retained earnings	17,140	17,101	16,606	16,214	15,980
Treasury stock, at cost	(11,251)	(10,855)	(10,616)	(10,626)	(10,472)
Accumulated other comprehensive loss	(2,057)	(2,063)	(2,059)	(2,076)	(2,356)
Total PPG shareholders’ equity	5,557	5,897	5,623	5,192	4,828
Noncontrolling interests	115	108	105	94	87
Total shareholders’ equity	5,672	6,005	5,728	5,286	4,915	$ 5,069	$ 5,265
Total	$ 16,538	$ 17,616	$ 16,973	$ 16,154	$ 15,771

Consolidated Statement of Share

Consolidated Statement of Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income/(Loss)	Total PPG	Non-controlling Interests
Beginning balance at Dec. 31, 2014	$ 5,265	$ 484	$ 1,028	$ 14,498	$ (8,714)	$ (2,116)	$ 5,180	$ 85
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	1,427			1,406			1,406	21
Other comprehensive loss, net of tax	(599)					(586)	(586)	(13)
Cash dividends	(383)			(383)			(383)
2:1 Stock split	0	485	(485)	0	0	0	0	0
Purchase of treasury stock	(751)				(751)		(751)
Issuance of treasury stock	71		46		25		71
Stock-based compensation activity	46		46				46
Dividends paid on subsidiary common stock to noncontrolling interests	(4)							(4)
Reductions in noncontrolling interests	(3)							(3)
Ending balance at Dec. 31, 2015	5,069	969	635	15,521	(9,440)	(2,702)	4,983	86
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	895			873			873	22
Other comprehensive loss, net of tax	336					346	346	(10)
Cash dividends	(414)			(414)			(414)
Purchase of treasury stock	(1,050)				(1,050)		(1,050)
Issuance of treasury stock	55		37		18		55
Stock-based compensation activity	35		35				35
Dividends paid on subsidiary common stock to noncontrolling interests	(4)							(4)
Reductions in noncontrolling interests	(7)		0				0	(7)
Ending balance at Dec. 31, 2016	4,915	969	707	15,980	(10,472)	(2,356)	4,828	87
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	342						337	5
Other comprehensive loss, net of tax	287						280	7
Cash dividends	(103)						(103)	0
Issuance of treasury stock	34						34	0
Stock-based compensation activity	(21)						(21)	0
Ending balance at Mar. 31, 2017	5,286						5,192	94
Beginning balance at Dec. 31, 2016	4,915	969	707	15,980	(10,472)	(2,356)	4,828	87
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	843						833	10
Other comprehensive loss, net of tax	310						297	13
Cash dividends	(205)						(205)	0
Issuance of treasury stock	49						49	0
Stock-based compensation activity	(16)						(16)	0
Ending balance at Jun. 30, 2017	5,728						5,623	105
Beginning balance at Dec. 31, 2016	4,915	969	707	15,980	(10,472)	(2,356)	4,828	87
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	1,459						1,443	16
Other comprehensive loss, net of tax	308						293	15
Cash dividends	(321)						(321)	0
Issuance of treasury stock	75						75	0
Stock-based compensation activity	(8)						(8)	0
Dividends paid on subsidiary common stock to noncontrolling interests	(5)							(5)
Ending balance at Sep. 30, 2017	6,005						5,897	108
Beginning balance at Dec. 31, 2016	4,915	969	707	15,980	(10,472)	(2,356)	4,828	87
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	1,615			1,594			1,594	21
Other comprehensive loss, net of tax	316					299	299	17
Cash dividends	(434)			(434)			(434)
Purchase of treasury stock	(813)				(813)		(813)
Issuance of treasury stock	83		49		34		83
Dividends paid on subsidiary common stock to noncontrolling interests	(5)							(5)
Reductions in noncontrolling interests	(5)		0				0	(5)
Ending balance at Dec. 31, 2017	5,672	969	756	17,140	(11,251)	(2,057)	5,557	115
Beginning balance at Mar. 31, 2017	5,286						5,192	94
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	501
Other comprehensive loss, net of tax	23
Ending balance at Jun. 30, 2017	5,728						5,623	105
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	616
Other comprehensive loss, net of tax	(2)
Ending balance at Sep. 30, 2017	6,005						5,897	108
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the controlling and noncontrolling interests	156
Ending balance at Dec. 31, 2017	$ 5,672	$ 969	$ 756	$ 17,140	$ (11,251)	$ (2,057)	$ 5,557	$ 115

Consolidated Statement of Cash

Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2017	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities
Net income attributable to the controlling and noncontrolling interests	$ 342	$ 843	$ 1,459	$ 1,615	$ 895	$ 1,427
Income from discontinued operations, net of tax	6	5	222	225	330	95
Income from continuing operations	336	838	1,237	1,390	565	1,332
Adjustments to reconcile to cash from operations:
Depreciation and amortization	110	223	340	460	440	446
Defined benefit pension expense	18	34	52	65	85	88
Pension settlement charge	22	22	22	60	968	0
Business restructuring				0	191	136
Environmental remediation charge				0	82	0
Stock-based compensation expense	9	17	26	35	45	54
Net gain, from sale of businesses	0	(25)	(25)	(25)	(39)	0
Equity affiliate (income)/loss, net of dividends	(1)	3	0	(4)	(6)	66
Deferred income taxes	6	(40)	(53)	38	171	0
Cash contributions to pension plans	(34)	(37)	(43)	(87)	(188)	(263)
Restructuring cash expenditures	(10)	(20)	(31)	(49)	(76)	(47)
Funding of asbestos settlement trust				0	(813)	0
Change in certain asset and liability accounts (net of acquisitions):
Receivables	(296)	(406)	(350)	(76)	(68)	(125)
Inventories	(157)	(185)	(200)	(116)	56	37
Other current assets	(47)	(49)	(40)	(43)	21	(81)
Accounts payable and accrued liabilities	62	147	229	188	169	152
Noncurrent assets and liabilities, net	39	(14)	(102)	(170)	(53)	79
Taxes and interest payable	(82)	(128)	(115)	(129)	(268)	(96)
Other	24	52	71	14	(64)	(19)
Cash from operating activities - continuing operations	(1)	432	1,018	1,551	1,218	1,759
Cash from operating activities - discontinued operations	10	14	14	17	133	136
Cash from operating activities	9	446	1,032	1,568	1,351	1,895
Investing activities
Additions to property and investments	(63)	(135)	(207)	(360)	(380)	(430)
Business acquisitions, net of cash balances acquired (See Note 2)	(61)	(62)	(69)	(225)	(349)	(320)
Payments for acquisition of equity investment	0	(100)	(100)	(100)	0	0
Net proceeds from the sale of businesses	0	52	593	593	1,094	47
Proceeds from maturity of short-term investments				0	92	402
Purchase of short-term investments	0	0	0	(1)	0	(97)
Payments for the settlement of cross currency swap contracts	(34)	(34)	(34)	(34)	(36)	(34)
Proceeds from the settlement of cross currency swap contracts	19	19	37	37	37	37
(Payments on) / Proceeds from net investment hedges				0	(13)	19
Other	2	2	0	27	27	27
Cash (used for)/from investing activities - continuing operations	(137)	(258)	220	(63)	472	(349)
Cash used for investing activities - discontinued operations	(1)	(3)	(4)	(4)	(36)	(46)
Cash (used for)/from investing activities	(138)	(261)	216	(67)	436	(395)
Financing activities
Net change in borrowings with maturities of three months or less	(7)	(3)	(6)	(7)	(15)	(32)
Net payments on commercial paper and short-term debt	(32)	(61)	(81)	(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)	(7)	(8)	(9)	(588)	(379)	(340)
Payments related to tax withholding on stock-based compensation awards	(16)	(20)	(25)	(28)	(26)	(58)
Purchase of treasury stock	(163)	(163)	(413)	(813)	(1,050)	(751)
Issuance of treasury stock	9	20	45	52	31	53
Dividends paid on PPG common stock	(103)	(205)	(321)	(434)	(414)	(383)
Other	(53)	(50)	(41)	(43)	16	(15)
Cash used for financing activities	(372)	(490)	(851)	(1,954)	(1,210)	(812)
Effect of currency exchange rate changes on cash and cash equivalents	30	54	70	69	(68)	(63)
Net (decrease) increase in cash and cash equivalents	(471)	(251)	467	(384)	509	625
Cash and cash equivalents, beginning of year	1,820	1,820	1,820	1,820	1,311	686
Cash and cash equivalents, end of year	1,349	1,569	2,287	1,436	1,820	1,311
Supplemental disclosures of cash flow information:
Interest paid, net of amount capitalized	23	52	60	100	118	115
Taxes paid, net of refunds	$ 90	$ 326	$ 481	$ 648	$ 349	$ 383

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation The accompanying consolidated financial statements include the accounts of PPG Industries, Inc. (“PPG” or the “Company”) and all subsidiaries, both U.S. and non-U.S., that it controls. PPG owns more than 50% of the voting stock of most of the subsidiaries that it controls. For those consolidated subsidiaries in which the Company’s ownership is less than 100% , the outside shareholders’ interests are shown as noncontrolling interests. Investments in companies in which PPG owns 20% to 50% of the voting stock and has the ability to exercise significant influence over operating and financial policies of the investee are accounted for using the equity method of accounting. As a result, PPG’s share of income or losses from such equity affiliates is included in the accompanying consolidated statement of income and PPG’s share of these companies’ shareholders’ equity is included in “Investments” in the accompanying consolidated balance sheet. Transactions between PPG and its subsidiaries are eliminated in consolidation. Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of income and expenses during the reporting period. Such estimates also include the fair value of assets acquired and liabilities assumed resulting from the allocation of the purchase price related to business combinations consummated. Actual outcomes could differ from those estimates. Revenue Recognition The Company recognizes revenue when the earnings process is complete. Revenue is recognized by all operating segments when goods are shipped and title to inventory and risk of loss passes to the customer or when services have been rendered. Shipping and Handling Costs Amounts billed to customers for shipping and handling are reported in “Net sales” in the accompanying consolidated statement of income. Shipping and handling costs incurred by the Company for the delivery of goods to customers are included in “Cost of sales, exclusive of depreciation and amortization” in the accompanying consolidated statement of income. Selling, General and Administrative Costs Amounts presented as “Selling, general and administrative” in the accompanying consolidated statement of income are comprised of selling, customer service, distribution and advertising costs, as well as the costs of providing corporate-wide functional support in such areas as finance, law, human resources and planning. Distribution costs pertain to the movement and storage of finished goods inventory at company-owned and leased warehouses and other distribution facilities. Advertising Costs Advertising costs are expensed as incurred and totaled $313 million , $ 322 million and $ 324 million in 2017 , 2016 and 2015 , respectively. Research and Development Research and development costs, which consist primarily of employee related costs, are charged to expense as incurred. ($ in millions) 2017 2016 2015 Research and development – total $474 $479 $484 Less depreciation on research facilities 21 20 18 Research and development, net $453 $459 $466 Legal Costs Legal costs, primarily include costs associated with acquisition and divestiture transactions, general litigation, environmental regulation compliance, patent and trademark protection and other general corporate purposes, are charged to expense as incurred. Foreign Currency Translation The functional currency of most significant non-U.S. operations is their local currency. Assets and liabilities of those operations are translated into U.S. dollars using year-end exchange rates; income and expenses are translated using the average exchange rates for the reporting period. Unrealized foreign currency translation gains and losses are deferred in accumulated other comprehensive loss, a separate component of shareholders’ equity. Cash Equivalents Cash equivalents are highly liquid investments (valued at cost, which approximates fair value) acquired with an original maturity of three months or less. Short-term Investments Short-term investments are highly liquid, high credit quality investments (valued at cost plus accrued interest) that have stated maturities of greater than three months to one year. The purchases and sales of these investments are classified as investing activities in the consolidated statement of cash flows. Marketable Equity Securities The Company’s investment in marketable equity securities is recorded at fair market value and reported in “Other current assets” and “Investments” in the accompanying consolidated balance sheet with changes in fair market value recorded in income for those securities designated as trading securities and in other comprehensive income, net of tax, for those securities designated as available for sale. Inventories Inventories are stated at the lower of cost or net realizable value. Most U.S. inventories are stated at cost, using the last-in, first-out (“LIFO”) method of accounting, which does not exceed net realizable value. All other inventories are stated at cost, using the first-in, first-out (“FIFO”) method of accounting, which does not exceed net realizable value. PPG determines cost using either average or standard factory costs, which approximate actual costs, excluding certain fixed costs such as depreciation and property taxes. See Note 4, “Working Capital Detail” for further information concerning the Company’s inventory. Derivative Financial Instruments The Company recognizes all derivative financial instruments (a “derivative”) as either assets or liabilities at fair value on the consolidated balance sheet. The accounting for changes in the fair value of a derivative depends on the use of the instrument. For a derivative that is considered “effective” as a hedge of an exposure to variability in expected future cash flows (cash flow hedge), the effective portion of the gain or loss on the derivative is recorded in other comprehensive income (“OCI”) and the ineffective portion, if any, is reported in income from continuing operations. Amounts accumulated in OCI are reclassified into income from continuing operations in the same period or periods during which the hedged transactions are recorded in income from continuing operations. For a derivative that is considered “effective” as a hedge of an exposure to changes in the fair value (fair value hedge) of an asset, a liability or a firm commitment, the change in the derivative’s fair value is reported in income from continuing operations, offsetting the gain or loss recognized for the change in fair value of the asset, liability, or firm commitment that is being hedged. For a derivative, debt or other financial instrument that is considered “effective” as a hedge of a net investment in a foreign operation, the gain or loss associated with the financial instrument is reported as a translation gain or loss in accumulated other comprehensive income (“AOCI”). Gains and losses in AOCI related to hedges of the Company’s net investments in foreign operations are reclassified out of AOCI and recognized in income from continuing operations upon a substantial liquidation, sale or partial sale of such investments or upon impairment of all or a portion of such investments. The cash flow impact of these instruments have been and will be classified as investing activities in the consolidated statement of cash flows. Changes in the fair value of derivative instruments not designated as hedges for hedge accounting purposes are recognized in income from continuing operations in the period of change. Property, Plant and Equipment Property, plant and equipment is recorded at cost. Depreciation is computed on a straight-line method based on the estimated useful lives of related assets. Additional depreciation expense is recorded when facilities or equipment are subject to abnormal economic conditions or obsolescence. The cost of significant improvements that add to productive capacity or extend the lives of properties are capitalized. Costs for repairs and maintenance are charged to expense as incurred. When a capitalized asset is retired or otherwise disposed of, the original cost and related accumulated depreciation balance are removed from the accounts and any related gain or loss is recorded in income from continuing operations. The amortization cost of capitalized leased assets is recorded in depreciation expense. Property and other long-lived assets are reviewed for impairment whenever events or circumstances indicate that their carrying amounts may not be recoverable. See Note 5, “Property, Plant and Equipment” for further details. Goodwill and Identifiable Intangible Assets Goodwill represents the excess of the cost over the fair value of acquired identifiable tangible and intangible assets less liabilities assumed from acquired businesses. Identifiable intangible assets acquired in business combinations are recorded based upon their fair value at the date of acquisition. The Company tests goodwill of each reporting unit for impairment at least annually in connection with PPG’s strategic planning process. The Company tests goodwill for impairment by either performing a qualitative evaluation or a quantitative test. The qualitative evaluation is an assessment of factors, including reporting unit specific operating results as well as industry, market and general economic conditions, to determine whether it is more likely than not that the fair values of a reporting unit is less than its carrying amount, including goodwill. The Company may elect to bypass this qualitative assessment for some or all of its reporting units and perform a quantitative test. The quantitative goodwill impairment test is performed during the fourth quarter by comparing the estimated fair value of the associated reporting unit as of September 30 to its carrying value. The Company’s reporting units are its operating segments. (See Note 20, “Reportable Business Segment Information,” for further information concerning the Company’s operating segments.) Fair value is estimated using discounted cash flow methodologies. The Company has determined that certain acquired trademarks have indefinite useful lives. The Company tests the carrying value of these trademarks for impairment at least annually, or as needed whenever events and circumstances indicate that their carrying amount may not be recoverable. The annual assessment takes place in the fourth quarter of each year either by completing a qualitative assessment or quantitatively by comparing the estimated fair value of each trademark as of September 30 to its carrying value. Fair value is estimated by using the relief from royalty method (a discounted cash flow methodology). The qualitative assessment includes consideration of factors, including revenue relative to the asset being assessed, the operating results of the related business as well as industry, market and general economic conditions, to determine whether it is more likely than not that the fair value of the asset is less than its carrying amount. Identifiable intangible assets with finite lives are amortized on a straight-line basis over their estimated useful lives ( 1 to 30 years) and are reviewed for impairment whenever events or circumstances indicate that their carrying amount may not be recoverable. Receivables and Allowances All trade receivables are reported on the balance sheet at the outstanding principal adjusted for any allowance for credit losses and any charge offs. The Company provides an allowance for doubtful accounts to reduce receivables to their estimated net realizable value when it is probable that a loss will be incurred. Those estimates are based on historical collection experience, current economic and market conditions, a review of the aging of accounts receivable and the assessments of current creditworthiness of customers. Product Warranties The Company accrues for product warranties at the time the associated products are sold based on historical claims experience. The reserve, pre-tax charges against income and cash outlays for product warranties were not significant to the consolidated financial statements of the Company for any year presented. Asset Retirement Obligations An asset retirement obligation represents a legal obligation associated with the retirement of a tangible long-lived asset that is incurred upon the acquisition, construction, development or normal operation of that long-lived asset. PPG recognizes asset retirement obligations in the period in which they are incurred, if a reasonable estimate of fair value can be made. The asset retirement obligation is subsequently adjusted for changes in fair value. The associated estimated asset retirement costs are capitalized as part of the carrying amount of the long-lived asset and depreciated over its useful life. PPG’s asset retirement obligations are primarily associated with the retirement or closure of certain assets used in PPG’s manufacturing process. The accrued asset retirement obligation recorded on PPG’s balance sheet was $19 million and $18 million as of December 31, 2017 and 2016 , respectively. PPG’s only conditional asset retirement obligation relates to the possible future abatement of asbestos contained in certain PPG production facilities. The asbestos in PPG’s production facilities arises from the application of normal and customary building practices in the past when the facilities were constructed. This asbestos is encapsulated in place and, as a result, there is no current legal requirement to abate it. Inasmuch as there is no requirement to abate, the Company does not have any current plans or an intention to abate and therefore the timing, method and cost of future abatement, if any, are not known. The Company has not recorded an asset retirement obligation associated with asbestos abatement, given the uncertainty concerning the timing of future abatement, if any. Reclassifications Certain reclassifications of prior years’ data have been made to conform to the current year presentation. These reclassifications had no impact on our previously reported net income, cash flows or shareholders’ equity. Accounting Standards Adopted in 2017 PPG’s adoption of the following accounting standard updates (“ASU”) in 2017 did not have a material impact on PPG's consolidated financial position, results of operations or cash flows: Accounting Standard Update 2017-04 Simplifying the Test for Goodwill Impairment 2016-18 Restricted Cash 2016-09 Improvements to Employee Share-Based Payment Accounting Accounting Standards to be Adopted in Future Years In February 2018, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2018-2, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” This ASU allows a reclassification from Accumulated other comprehensive income to Retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. Early adoption of this ASU is permitted. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging - Targeted Improvements to Accounting for Hedging Activities." This ASU modifies the presentation and disclosure of hedging results. Further, it provides partial relief on the timing of certain aspects of hedge documentation and eliminates the requirement to recognize hedge ineffectiveness separately in income. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. Early adoption of this ASU is permitted. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In May 2017, the FASB issued ASU No. 2017-09, "Stock Compensation - Scope of Modification Accounting." This ASU requires all equity award modifications to be accounted for as a modification unless the fair value, vesting conditions and classification of the award as equity or liability are the same as the classification of the original award immediately before the original award is modified. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In March 2017, the FASB issued ASU No. 2017-07, "Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost." This ASU requires the service cost component of net benefit costs to be disaggregated from all other components and be reported in the same line item or items as other compensation costs. The other components of net benefit cost are required to be presented in the income statement separately from the service cost. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operation or cash flows. Beginning January 1, 2018, in connection with the adoption of this new ASU, PPG will change the method by which pension costs are allocated to its strategic business units. Namely, only service costs will be attributed to the strategic business units and all other components will remain in unallocated corporate overhead. PPG will recast its statement of operations and segment income for this change in allocation. In August 2016, the FASB issued ASU No. 2016-15, "Classification of Certain Cash Receipts and Cash Payments." This ASU addresses eight specific cash flow issues with the objective of eliminating the existing diversity in practice. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses.” This ASU requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. The amendments in this ASU are effective for fiscal years beginning after December 15, 2019 and for interim periods therein. Entities may chose to adopt the new ASU as of its fiscal year beginning after December 15, 2018. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In February 2016, the FASB issued ASU No. 2016-02, “Leases.” This ASU requires all lessees to recognize on the balance sheet right to use assets and lease liabilities for the rights and obligations created by lease arrangements with terms greater than 12 months. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. PPG is in the process of assessing the impact the adoption of this ASU will have on its consolidated financial position, results of operations and cash flows. At a minimum, total assets and total liabilities will increase in the period the ASU is adopted. Early adoption of this ASU is permitted. At December 31, 2017, PPG’s undiscounted future minimum payments outstanding for lease obligations were approximately $840 million . In January 2016, the FASB issued ASU No. 2016-01, “Recognition and Measurement of Financial Assets and Liabilities.” This ASU simplifies the accounting and disclosures related to equity investments. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. Adoption of this ASU will not have a material impact on PPG’s consolidated financial position, results of operations or cash flows. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers: Topic 606.” This ASU replaces nearly all existing U.S. GAAP guidance on revenue recognition. The standard prescribes a five-step model for recognizing revenue, the application of which will require significant judgment. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017, and for interim periods therein. The provisions of this ASU may be applied retroactively or on a modified retrospective (cumulative effect) basis. PPG will adopt the standard using the modified retrospective approach in January 2018. PPG believes the preponderance of the Company’s contracts with customers are standard ship and bill arrangements where revenue is recognized at the time of shipment. Under the provisions of this ASU, PPG believes certain costs currently reported in Selling, general and administrative costs will be reclassified to Cost of sales, exclusive of depreciation and amortization on the Consolidated Statement of Income, as they represent costs incurred in satisfaction of performance obligations. In addition, PPG expects the cost of certain customer incentives to be recorded as a reduction of Net sales rather than Cost of sales, exclusive of depreciation and amortization or Selling, general and administrative costs. Adoption of this ASU will not have a significant impact on PPG’s consolidated financial position, results of operations and cash flows.

Acquisitions and Dispositions

Acquisitions and Dispositions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions and Dispositions	Acquisitions and Divestitures (As Restated) Acquisitions The Crown Group On October 2, 2017, PPG acquired The Crown Group (“Crown”), a U.S.-based coatings application services business, which is reported as part of PPG's Industrial Coatings reportable segment. Crown is one of the leading component and product finishers in North America. Crown applies coatings to customers’ manufactured parts and assembled products at 11 U.S. sites. Most of Crown’s facilities, which also provide assembly, warehousing and sequencing services, are located at customer facilities or positioned near customer manufacturing sites. The company serves manufacturers in the automotive, agriculture, construction, heavy truck and alternative energy industries. Crown has annual sales of approximately $125 million . Taiwan Chlorine Industries Taiwan Chlorine Industries (“TCI”) was established in 1986 as a joint venture between PPG and China Petrochemical Development Corporation (“CPDC”) to produce chlorine-based products in Taiwan, at which time PPG owned 60 percent of the venture. In conjunction with the 2013 separation of its commodity chemicals business, PPG conveyed to Axiall Corporation ("Axiall") its 60% ownership interest in TCI. Under PPG’s agreement with CPDC, if certain post-closing conditions were not met following the three year anniversary of the separation, CPDC had the option to sell its 40% ownership interest in TCI to Axiall for $100 million . In turn, Axiall had a right to designate PPG as its designee to purchase the 40% ownership interest of CPDC. In April 2016, Axiall announced that CPDC had decided to sell its ownership interest in TCI to Axiall. In June 2016, Axiall formally designated PPG to purchase the 40% ownership interest in TCI. In August 2016, Westlake Chemical Corporation acquired Axiall, which became a wholly-owned subsidiary of Westlake. On April 11, 2017, PPG finalized its purchase of CPDC’s 40% ownership interest in TCI. The difference between the acquisition date fair value and the purchase price of PPG’s 40% ownership interest in TCI has been recorded as a loss in discontinued operations during the year-ended December 31, 2017. MetoKote Corporation In July 2016, PPG completed the acquisition of MetoKote Corporation ("MetoKote"), a U.S.-based coatings application services business. MetoKote applies coatings to customers' manufactured parts and assembled products. It operates on-site coatings services within several customer manufacturing locations, as well as at regional service centers, located throughout the U.S., Canada, Mexico, the United Kingdom, Germany, Hungary and the Czech Republic. Customers ship parts to MetoKote service centers where they are treated to enhance paint adhesion and painted with electrocoat, powder or liquid coatings technologies. Coated parts are then shipped to the customer’s next stage of assembly. MetoKote coats an average of more than 1.5 million parts per day. The following table summarizes the estimated fair value of assets acquired and liabilities assumed as reflected in the final purchase price allocation for MetoKote. ($ in millions) Current assets $38 Property, plant, and equipment 73 Identifiable intangible assets with finite lives 86 Goodwill 166 Deferred income taxes (a) (12 ) Total assets $351 Current liabilities (23 ) Other long-term liabilities (22 ) Total liabilities ($45 ) Total purchase price, net of cash acquired $306 (a) The net deferred income tax liability is included in assets due to the Company's tax jurisdictional netting. The pro-forma impact on PPG's sales and results of operations, including the pro forma effect of events that are directly attributable to the acquisition, was not significant. While calculating this impact, no cost savings or operating synergies that may result from the acquisition were included. Since the acquisition, the results of this acquired business comprise the coatings services operating segment, included within the Industrial Coatings reportable segment. Other Acquisitions In 2017 , 2016 , and 2015 , the Company completed several smaller business acquisitions. The total consideration paid for these acquisitions, net of cash acquired, debt assumed and other post closing adjustments, was $74 million , $43 million and $371 million , respectively. In January 2018, PPG acquired ProCoatings, a leading architectural paint and coatings wholesaler located in The Netherlands. ProCoatings, established in 2001, distributes a large portfolio of well-known professional paint brands through its network of 23 multi-brand stores. The company employs nearly 100 people. Divestitures Glass Segment (As Restated) In 2017, PPG completed a multi-year strategic shift in the Company's business portfolio, resulting in the exit of all glass operations which consisted of the global fiber glass business, PPG's ownership interest in two Asian fiber glass joint ventures and the flat glass business. Accordingly, the results of operations, including the gains on the divestitures, and cash flows have been recast as discontinued operations for all periods presented. PPG now has two reportable business segments. The net sales and income from discontinued operations related to the former Glass segment for the three years ended December 31, 2017 , 2016 , and 2015 were as follows: ($ in millions) 2017 2016 2015 As Restated Net sales $217 $908 $1,089 Income from operations $30 $111 $137 Net gains on the divestitures of businesses 343 421 — Income tax expense 140 202 42 Income from discontinued operations, net of tax $233 $330 $95 North American Fiber Glass Business On September 1, 2017, PPG completed the sale of its North American fiber glass business to Nippon Electric Glass Co. Ltd. (“NEG”). Cash proceeds from the sale were $541 million , resulting in a pre-tax gain of $343 million , net of certain accruals and contingencies established in conjunction with the divestiture. PPG’s fiber glass operations included manufacturing facilities in Chester, South Carolina, and Lexington and Shelby, North Carolina; and administrative and research-and-development operations in Shelby and in Harmar, Pennsylvania, near Pittsburgh. The business, which employed more than 1,000 people and had net sales of approximately $350 million in 2016, supplies the transportation, energy, infrastructure and consumer markets. The Company's December 31, 2016 consolidated balance sheet has been recast to present the assets and liabilities of the North American fiber glass business as held for sale. The major classes of assets and liabilities of the Glass segment included in the PPG consolidated balance sheet at December 31, 2016 were as follows: ($ in millions) December 31, 2016 Receivables. net $38 Inventory 32 Other current assets 1 Property, plant, and equipment, net 151 Deferred income taxes (a) (30 ) Other non-current assets 1 Assets held for sale $193 Accounts payable and accrued liabilities 52 Long-term liabilities 12 Liabilities held for sale $64 (a) The net deferred income tax liability is included in assets held for sale due to the Company's tax jurisdictional netting. Flat Glass Business In October 2016, PPG completed the sale of its flat glass manufacturing and glass coatings operations to Vitro S.A.B. de C.V. PPG received approximately $740 million in cash proceeds and recorded a pre-tax gain of $421 million on the sale. Under the terms of the agreement, PPG divested its entire flat glass manufacturing and glass coatings operations, including production sites located in Fresno, California; Salem, Oregon; Carlisle, Pennsylvania; and Wichita Falls, Texas; four distribution/fabrication facilities located across Canada; and a research-and-development center located in Harmar, Pennsylvania. PPG’s flat glass business included approximately 1,200 employees. The business manufactures glass that is fabricated into products used primarily in commercial and residential construction. European Fiber Glass Business In October 2016, PPG completed the sale of its European fiber glass business to glass manufacturer NEG. PPG recorded a pre-tax loss of $42 million , consisting predominately of a $46 million pension settlement charge. The European fiber glass business manufactures reinforcement materials for thermoset and thermoplastic composite applications for the transportation, energy, infrastructure and consumer markets. Manufacturing facilities in Hoogezand, Netherlands, and Wigan, England, and a research and development facility in Hoogezand were included in the transaction. PFG Fiber Glass Joint Ventures In November 2016, PPG sold its 50% ownership interests in its two PFG fiber glass joint ventures to its joint venture partner Nan Ya Plastics Corporation (“Nan Ya”). Nan Ya is affiliated with Taiwan-based Formosa Plastics Group. The PFG fiber glass joint ventures supply electronic yarn fibers used in integrated electronic circuit boards and fiber glass reinforcement products for automotive applications. PPG recorded a net pre-tax gain of $36 million on the sale. Other Divestitures Plaka Business In June 2017, PPG completed the sale of the assets of its Mexico-based Plaka plasterboard and cement-board business to Knauf International GmbH and recorded a $25 million pre-tax gain on the sale. The Company's consolidated balance sheet presents the assets and liabilities of the Plaka business as held for sale as of December 31, 2016. Pittsburgh Glass Works In April 2016, PPG sold its minority ownership interest in Pittsburgh Glass Works LLC ("PGW") to LKQ Corporation concurrent with the majority partner’s sale of its ownership interest. PPG recorded a pre-tax gain on the sale of $20 million . PPG accounted for its interest in PGW under the equity method of accounting. PPG’s share of net earnings from PGW are reported in “Other income” in the Consolidated Statement of Income for all periods presented and have not been reclassified as discontinued operations, as the divestiture of PGW does not represent a strategic shift in PPG’s operations and PGW did not have a major impact on PPG's ongoing results of operations.

Restatement of Previously Repor

Restatement of Previously Reported Consolidated Annual Financial Statements	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Restatement of Previously Reported Consolidated Annual Financial Statements	Restatement of Previously Reported Consolidated Annual Financial Statements Background On April 16, 2018, PPG received a report through the Company’s internal reporting system alleging violations of the Company’s accounting policies and procedures regarding the failure to accrue certain specified expenses in the first quarter of 2018. Based on the Company’s initial review at that time, the Company identified approximately $1.4 million of expenses (including legal fees, property taxes and performance-based compensation) that should have been accrued in the first quarter of 2018 and that were then reflected in PPG’s earnings for the quarter ended March 31, 2018, released on April 19, 2018. In addition, the report alleged that there may have been other unspecified expenses, potentially up to $5 million in the aggregate, that were improperly not accrued in the first quarter. The Audit Committee oversaw an investigation of the matters set forth in the internal report, with the assistance of outside counsel and forensic accountants. The investigation identified the following items with respect to the quarter ended March 31, 2018, in addition to the approximately $1.4 million of expenses described above: (1) failure to record amortization expense in the amount of $1.4 million to correct for amortization of an intangible asset that was inadvertently not recorded over a three-year period and discovered in March 2018; (2) understatement of a health insurance accrued liability in the amount of $0.5 million ; and (3) failure to record an adjustment increasing the value of inventory in PPG’s Europe, Middle East and Africa region in the amount of $2.2 million due to inflation of raw materials costs which, when corrected, had a positive effect on income in the first quarter of 2018. These three items resulted in a net increase to income from continuing operations before income taxes of approximately $0.3 million . The investigation also identified certain inadvertent errors with respect to the quarter ended March 31, 2018. Correction of such inadvertent errors, together with the matters discussed in the immediately preceding paragraph, resulted in a net decrease in income from continuing operations before income taxes of $5.7 million for the quarter ended March 31, 2018. The correction of these inadvertent errors also resulted in a net decrease in income from continuing operations before income taxes of $2.3 million for the year ended December 31, 2017. The investigation identified the following items with respect to the year ended December 31, 2017: (1) improper reclassifications of gains from income from discontinued operations to income from continuing operations, in total pre-tax amounts of $2.5 million in the quarter ended June 30, 2017 and $4.7 million in the quarter ended December 31, 2017; (2) improper shifting of pre-tax expenses between quarterly periods in 2017, including a total of $3.5 million in compensation expense recorded in the third and fourth quarters of 2017 that should have been recorded in the quarter ended June 30, 2017; an additional expense accrual for health care claims in the amount of $3.5 million recorded in the third quarter of 2017 that should have been recorded in the quarter ended June 30, 2017; additional expense for paid vacation in the amount of $2.2 million recorded in the quarter ended December 31, 2017 that should have been recorded in the second and third quarters of 2017; and additional pension expense in the amount of $1.0 million recorded in the fourth quarter of 2017 that should have been recorded in the quarter ended September 30. 2017. On May 10, 2018, management, in consultation with the Audit Committee and the Company’s independent registered public accounting firm, PwC, concluded that the Company’s consolidated financial statements for the year ended December 31, 2017 included in the Original Filing and the related report of PwC, and for the quarterly and year-to-date periods in 2017, should no longer be relied upon because of certain misstatements contained in those financial statements. The investigation identified the following items with respect to the year ended December 31, 2016: (1) improper classification in the consolidated statement of income of the release of a reserve related to the Company’s 2015 business restructuring program in the amount of $3.4 million and (2) an improper reduction in the payout assumption for certain performance-based restricted stock units that had the impact of recognizing a $6.8 million reduction in stock-based compensation expense in the fourth quarter of 2016. In the first quarter of 2017, the payout assumption for these same performance-based restricted stock units was increased, resulting in $6.8 million of stock-based compensation expense in the first quarter of 2017 that would not have been recorded if the payout assumption had not been reduced in the fourth quarter of 2016. On June 27, 2018, management, in consultation with the Audit Committee and PwC, concluded that the Company’s consolidated financial statements for the year ended December 31, 2016 included in the Original Filing and the related report of PwC, and for the final quarterly and year-to-date period in 2016, should no longer be relied upon because of certain misstatements contained in those financial statements. On June 27, 2018, the Audit Committee determined that its investigation was complete, and authorized the filing of our restated audited consolidated financial statements for the years ended December 31, 2017 and 2016 and certain quarterly periods within those fiscal years in order to correct our previously issued financial statements. Impact of the Restatement Annual As a result of the restatement, reported net income from continuing operations was decreased by $2 million , or $0.01 per diluted share, and income from discontinued operations, net of tax, was increased by $5 million , or $0.02 per diluted share, for the year ended December 31, 2017. Reported net income from continuing operations decreased by $4 million , or $0.01 per diluted share, and there was no impact to income from discontinued operations, net of tax, for the year ended December 31, 2016. The categories of misstatements and their impact on previously reported consolidated financial statements for the 2017 and 2016 annual periods are described below: (a) Customer Rebates The Company did not properly recognize expense associated with certain customer rebates, resulting in a misstatement of Net sales in 2017. The misstatement overstated previously reported Income before taxes by $1.8 million for the year ended December 31, 2017. (b) Classification of Continuing Operations and Discontinued Operations Certain items of income related to PPG’s former Glass segment were inappropriately recorded in continuing operations rather than in discontinued operations. The misstatements overstated previously reported Income before income taxes from continuing operations by $7.2 million for the year ended December 31, 2017. The misstatement understated previously recorded Income from discontinued operations, net of tax, by $4.5 million for the year ended December 31, 2017. (c) Stock-Based Compensation In the fourth quarter of 2016, the Company improperly reduced the payout assumption for the 2015 grant of performance-based restricted stock units from 150% to 100% , which had the effect of reducing stock-based compensation expense in that period by $6.8 million . In the first quarter of 2017, the Company increased the payout assumption for these same restricted stock units from 100% back to 150% . These improper changes to the payout assumption for these restricted stock units resulted in a misstatement of stock-based compensation expense in both 2016 and 2017. (See Note 18, “Stock-Based Compensation (As Restated),” for further information concerning the Company’s accounting for Restricted Stock Units.) The misstatements overstated previously reported Income before income taxes by $6.8 million for the year ended December 31, 2016 and understated previously reported Income before income taxes by $6.8 million for the year ended December 31, 2017. (d) Environmental Reserve In 2017, the Company failed to appropriately update the discount rate used to calculate a long-term environmental remediation reserve, which had the effect of understating Other expense by $0.5 million . The misstatement overstated previously reported Income before taxes by $0.5 million for the year ended December 31, 2017. (e) Classification of Business Restructuring Expense The Company misclassified the release of the unused portion of the reserve related to the 2015 business restructuring program in 2016 of $3.4 million . The income associated with the release of the reserve was classified as Other income rather than as a reduction to Business restructuring in the Consolidated Statement of Income. The misclassification had no impact on Income before taxes. (f) Income Taxes Adjustments related to the income tax effects of other restatement adjustments noted above. The financial statements included in this Form 10-K/A have been restated to reflect the adjustments described above. The tables below summarize the effects of the restatement on PPG’s Consolidated Statements of Income for the years ended December 31, 2017 and 2016, Consolidated Statements of Comprehensive Income for the years ended December 31, 2017 and 2016, and Consolidated Balance Sheets at December 31, 2017 and 2016. In addition to the restatement of the financial statements, certain information within the following notes to the financial statements and financial statement schedule has been restated to reflect the corrections of misstatements discussed above as well as to add disclosure language as appropriate: Note 3. Acquisitions and Divestitures Note 4. Working Capital Detail Note 8. Business Restructuring Note 11. Earnings Per Common Share Note 12. Income Taxes Note 17. Other Income Note 18. Stock-Based Compensation Note 20. Reportable Business Segment Information Additionally, see Note 19 “Quarterly Financial Information (unaudited) (As Restated)” for the Condensed Consolidated financial statements and notes to the condensed consolidated financial statements (unaudited) as well as tables that summarize the effects of the restatement on the Condensed Consolidated Statements of Income, Condensed Consolidated Statements of Comprehensive Income and Condensed Consolidated Balance Sheets for the appropriate quarterly periods within 2017 and 2016.

Working Capital Detail

Working Capital Detail	12 Months Ended
	Dec. 31, 2017
Disclosure Components Of Working Capital Detail [Abstract]
Working Capital Detail	Working Capital Detail (As Restated) ($ in millions) 2017 2016 As Restated Receivables Trade - net (1) $2,559 $2,288 Equity affiliates 5 2 Other - net 339 364 Total $2,903 $2,654 Inventories (2) Finished products $1,083 $947 Work in process 177 165 Raw materials 437 370 Supplies 33 32 Total $1,730 $1,514 Accounts payable and accrued liabilities Trade $2,321 $1,907 Accrued payroll 441 443 Customer rebates 261 235 Other postretirement and pension benefits 78 124 Income taxes 100 94 Other 580 657 Total $3,781 $3,460 (1) Allowance for Doubtful Accounts was $25 million and $36 million as of December 31, 2017 and 2016 , respectively. (2) Inventories valued using the LIFO method of inventory valuation comprised 34% and 38% of total gross inventory values as of December 31, 2017 and 2016 , respectively. If the FIFO method of inventory valuation had been used, inventories would have been $103 million and $106 million higher as of December 31, 2017 and 2016 , respectively. During the years ended December 31, 2017 and 2016 , certain inventories accounted for on the LIFO method of accounting were reduced, which resulted in the liquidation of certain quantities carried at costs prevailing in prior years. The effect on income from continuing operations was zero and income of $2 million for the years ended December 31, 2017 and 2016 , respectively.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment ($ in millions) Useful Lives (years) 2017 2016 Land and land improvements 1-30 $487 $451 Buildings 20-40 1,488 1,324 Machinery and equipment 5-25 3,432 3,076 Other 3-20 958 774 Construction in progress 229 380 Total (1) $6,594 $6,005 Less: accumulated depreciation 3,770 3,397 Net $2,824 $2,608 (1) Interest capitalized in 2017 , 2016 and 2015 was $7 million , $8 million and $9 million , respectively.

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Investments	Investments ($ in millions) 2017 2016 Investments in equity affiliates $135 $46 Marketable equity securities - Trading (See Note 9) 79 78 Other 54 55 Total $268 $179 The Company’s investments in equity affiliates are comprised principally of 50% ownership interests in a number of joint ventures that manufacture and sell coatings. In 2017, PPG purchased a 40% ownership interest in TCI. Refer to Note 3, “Acquisitions and Divestitures” for additional information. PPG’s share of undistributed net earnings of equity affiliates was $12 million and $7 million as of December 31, 2017 and December 31, 2016 , respectively. Dividends received from equity affiliates were $8 million , $7 million and $77 million in 2017 , 2016 and 2015 , respectively.

Goodwill and Other Identifiable

Goodwill and Other Identifiable Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Identifiable Intangible Assets	Goodwill and Other Identifiable Intangible Assets Goodwill ($ in millions) Performance Coatings Industrial Coatings Total January 1, 2016 $3,073 $552 $3,625 Acquisitions 6 168 174 Foreign currency translation (209 ) (18 ) (227 ) December 31, 2016 $2,870 $702 $3,572 Acquisitions 23 89 112 Foreign currency translation 211 47 258 December 31, 2017 $3,104 $838 $3,942 Identifiable Intangible Assets December 31, 2017 December 31, 2016 ($ in millions) Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Indefinite-Lived Identifiable Intangible Assets Trademarks $1,158 $— $1,158 $1,107 $— $1,107 Definite-Lived Identifiable Intangible Assets Acquired technology $613 ($489 ) $124 $587 ($446 ) $141 Customer-related 1,437 (762 ) 675 1,272 (618 ) 654 Tradenames 166 (87 ) 79 142 (71 ) 71 Other 44 (35 ) 9 38 (28 ) 10 Total Definite Lived Intangible Assets $2,260 ($1,373 ) $887 $2,039 ($1,163 ) $876 Total Identifiable Intangible Assets $3,418 ($1,373 ) $2,045 $3,146 ($1,163 ) $1,983 The Company’s identifiable intangible assets with definite lives are being amortized over their estimated useful lives. Aggregate amortization expense was $129 million , $121 million and $132 million in 2017 , 2016 and 2015 , respectively. ($ in millions) 2018 2019 2020 2021 2022 Estimated future amortization expense $125 $115 $105 $100 $100

Business Restructuring

Business Restructuring	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Business Restructuring	Business Restructuring (As Restated) The Company records restructuring liabilities that represent charges incurred in connection with consolidations of certain operations, including operations from acquisitions, as well as headcount reduction programs. These charges consist primarily of severance costs and asset write-downs. In December 2016, PPG’s Board of Directors approved a business restructuring program which includes actions necessary to reduce its global cost structure. The program is focused on certain regions and end-use markets where business conditions are the weakest, as well as reductions in production capacity and various global functional and administrative costs. A pre-tax restructuring charge of $191 million (as restated) was recorded in December 2016, representing $195 million of restructuring actions, net of the reversal of the remaining reserve of $4 million related to the 2015 restructuring program that was completed in 2016. Related to the $195 million of new restructuring actions approved in December 2016, approximately $136 million represents employee severance and other cash costs and $59 million is related to the write-down of certain assets held for sale and other non-cash costs. The restructuring actions will result in the net reduction of approximately 1,700 positions, with substantially all actions to be completed in the first half of 2018. 2016 Restructuring and Associated Reserve Activity ($ in millions, except no. of employees) Severance and Other Costs Asset Write-offs Total Reserve Employees Impacted Performance Coatings $77 $45 $122 1,069 Industrial Coatings 52 14 66 804 Corporate 7 — 7 85 Total 2016 restructuring charge $136 $59 $195 1,958 2016 Activity (6 ) (59 ) (65 ) (40 ) December 31, 2016 $130 $— $130 1,918 2017 Activity (46 ) — (46 ) (969 ) Foreign currency impact 18 — 18 — December 31, 2017 $102 $— $102 949

Borrowings and Lines of Credit

Borrowings and Lines of Credit	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Borrowings and Lines of Credit	Borrowings and Lines of Credit Long-term Debt Obligations ($ in millions) Maturity Date 2017 2016 3-year variable rate bank loan (€500) 2017 $— $526 0.00% note (€300) 2019 358 313 2.3% notes 2019 299 298 3.6% notes 2020 497 496 9% non-callable debentures (1) 2021 133 133 0.875% notes (€600) 2022 716 626 0.875% note (€600) 2025 710 621 1.4% notes (€600) 2027 711 620 2.5% note (€80) 2029 95 83 7.70% notes 2038 174 174 5.5% notes 2040 247 247 3% note (€120) 2044 137 118 Various other non-U.S. debt (2) Various 43 41 Capital lease obligations Various 15 18 Impact of derivatives on debt (1) N/A 3 3 Total $4,138 $4,317 Less payments due within one year N/A 4 530 Long-term debt $4,134 $3,787 (1) PPG entered into several interest rate swaps which had the effect of converting fixed rate notes to variable rates, based on the three-month London Interbank Offered Rate (LIBOR). There were no interest rate swaps outstanding related to these instruments as of December 31, 2017 and 2016 . The impact of the derivatives on debt represents the fair value adjustment of the debt while the interest rate swaps were outstanding, which is being amortized as a reduction to interest expense over the remaining term of the debt. The weighted average effective interest rate for these borrowings, including the effects of the swaps, was 8.4% and 8.4% for the years ended December 31, 2017 and 2016 , respectively. Refer to Note 10, “Financial Instruments, Hedging Activities, and Fair Value Measurements” for additional information. (2) Weighted average interest rate of 3.7% and 3.8% as of December 31, 2017 and 2016 , respectively. 2017 Activities In November 2017, PPG’s €500 million 3-year variable rate bank loan matured and the Company repaid this obligation using $587 million cash on hand. 2016 Activities In December 2016, PPG’s $125 million 6.65% notes, due 2018, were redeemed using $133 million cash on hand. Also, the Company prepaid its $250 million Term Loan Credit Agreements, one with the Bank of Tokyo-Mitsubishi UFJ, Ltd. and the other with BNP Paribas, which PPG entered into during May 2016. The Bank of Tokyo-Mitsubishi UFJ, Ltd. Term Loan would have originally terminated and all amounts outstanding would have been payable in March 2017. The BNP Paribas Term Loan would have originally terminated and all amounts outstanding would have been payable in May 2017. In November 2016, PPG completed a public offering of €300 million 0.000% Notes due 2019 and €600 million 0.875% Notes due 2025. These notes were issued pursuant to PPG’s existing shelf registration statement and pursuant to an indenture between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee, as supplemented. The Indenture governing these notes contains covenants that limit the Company’s ability to, among other things, incur certain liens securing indebtedness, engage in certain sale-leaseback transactions, and enter into certain consolidations, mergers, conveyances, transfers or leases of all or substantially all the Company’s assets. The terms of these notes also require the Company to make an offer to repurchase Notes upon a Change of Control Triggering Event (as defined in the Indenture) at a price equal to 101% of their principal amount plus accrued and unpaid interest. The Company may issue additional debt from time to time pursuant to the Indenture. The aggregate cash proceeds from the notes, net of discounts and fees, was $987 million . The notes are denominated in euro and have been designated as hedges of net investments in the Company’s European operations. For more information, refer to Note 10 “Financial Instruments, Hedging Activities and Fair Value Measurements.” In January 2016, PPG’s $250 million 1.9% notes matured, and the Company repaid these obligations using cash on hand. 2015 Activities In December 2015, PPG entered into a five -year credit agreement (the “Credit Agreement”) with several banks and financial institutions. The Credit Agreement replaced the Company's Five Year Credit Agreement dated as of September 12, 2012. The Credit Agreement provides for a $1.8 billion unsecured revolving credit facility. The Company has the ability to increase the size of the Credit Agreement by up to an additional $500 million , subject to the receipt of lender commitments and other conditions. The Credit Agreement will terminate on December 18, 2020. The Company has the right, subject to certain conditions set forth in the Credit Agreement, to designate certain subsidiaries of the Company as borrowers under the Credit Agreement. In connection with any such designation, the Company is required to guarantee the obligations of any such subsidiaries under the Credit Agreement. There were no amounts outstanding under the Credit Agreement during the years ended December 31, 2017 and 2016. The available borrowing rate on a one month, U.S. dollar denominated borrowing was 2.56% at December 31, 2017 . Borrowings under the Credit Agreement may be made in U.S. dollars or in euros. The Credit Agreement provides that loans will bear interest at rates based, at the Company’s option, on one of two specified base rates plus a margin based on certain formulas defined in the Credit Agreement. Additionally, the Credit Agreement contains a Commitment Fee, as defined in the Credit Agreement, on the amount of unused commitments under the Credit Agreement ranging from 0.080% to 0.225% per annum. The average Commitment Fee in 2017 was 0.09% , and PPG is committed to pay 0.09% in 2018 . The Credit Agreement also supports the Company’s commercial paper borrowings. There were no commercial paper borrowings outstanding as of December 31, 2017 and 2016. The Credit Agreement contains usual and customary restrictive covenants for facilities of its type, which include, with specified exceptions, limitations on the Company’s ability to create liens or other encumbrances, to enter into sale and leaseback transactions and to enter into consolidations, mergers or transfers of all or substantially all of its assets. The Credit Agreement maintains the same restrictive covenant as the prior credit agreement whereby the Company must maintain a ratio of Total Indebtedness to Total Capitalization, as defined in the Credit Agreement, of 60% or less. As of December 31, 2017 , total indebtedness was 41% of the Company’s total capitalization. The Credit Agreement also contains customary events of default, including the failure to make timely payments when due under the Credit Agreement or other material indebtedness, the failure to satisfy covenants contained in the Credit Agreement, a change in control of the Company and specified events of bankruptcy and insolvency that would permit the lenders to accelerate the repayment of any loans. In June 2015, PPG’s €300 million 3.875% notes matured and the Company repaid these obligations using $336 million of cash on hand. In March 2015, PPG completed a public offering of €600 million 0.875% notes due 2022 and €600 million 1.400% Notes due 2027, or €1.2 billion ( $1.26 billion ) in aggregate principal amount. These notes were issued pursuant to PPG’s existing shelf registration statement and pursuant to an indenture between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee, as supplemented. The Indenture governing these notes contains covenants that limit the Company’s ability to, among other things, incur certain liens securing indebtedness, engage in certain sale-leaseback transactions, and enter into certain consolidations, mergers, conveyances, transfers or leases of all or substantially all the Company’s assets. The terms of these notes also require the Company to make an offer to repurchase notes upon a Change of Control Triggering Event (as defined in the Indenture) at a price equal to 101% of their principal amount plus accrued and unpaid interest. The Company may issue additional debt from time to time pursuant to the Indenture. The aggregate cash proceeds from the notes, net of discounts and fees, was $1.24 billion . The notes are denominated in euro and have been designated as hedges of net investments in the Company’s European operations. For more information, refer to Note 10 “Financial Instruments, Hedging Activities and Fair Value Measurements.” Restrictive Covenants and Cross-Default Provisions As of December 31, 2017 , PPG was in full compliance with the restrictive covenants under its various credit agreements, loan agreements and indentures. Additionally, the Company’s Credit Agreement contains customary cross-default provisions. These provisions provide that a default on a debt service payment of $50 million or more for longer than the grace period provided under another agreement may result in an event of default under this agreement. The Company’s 9% non-callable debentures also contain a customary cross default provision triggered by the Company’s default on a debt service payment of $10 million or more. None of the Company’s primary debt obligations are secured or guaranteed by the Company’s affiliates. Long-term Debt Maturities ($ in millions) Maturity per year 2018 $4 2019 659 2020 497 2021 133 2022 718 Thereafter $2,127 Short-term Debt Obligations ($ in millions) 2017 2016 Various, weighted average 1.9% and 5.8% as of December 31, 2017 and 2016, respectively. $8 $99 Lease Obligations Rental expense for operating leases was $288 million , $273 million and $260 million in 2017 , 2016 and 2015 , respectively. The primary leased assets include paint stores, transportation equipment, warehouses and other distribution facilities, and office space, including the Company’s corporate headquarters located in Pittsburgh, Pa. Minimum lease commitments for operating leases that have initial or remaining lease terms in excess of one year are as follows: ($ in millions) As of December 31, 2017 2018 $212 2019 167 2020 138 2021 86 2022 63 Beyond 2022 $174 Lines of Credit, Letters of Credit, Surety Bonds and Guarantees PPG’s non-U.S. operations have uncommitted lines of credit totaling $589 million of which $2 million was used as of December 31, 2017 . These uncommitted lines of credit are subject to cancellation at any time and are generally not subject to any commitment fees. The Company had outstanding letters of credit and surety bonds of $163 million and $160 million as of December 31, 2017 and 2016 , respectively. The letters of credit secure the Company’s performance to third parties under certain self-insurance programs and other commitments made in the ordinary course of business. As of December 31, 2017 and 2016 , guarantees outstanding were $14 million and $12 million , respectively. The guarantees relate primarily to debt of certain entities in which PPG has an ownership interest and selected customers of certain PPG businesses. A portion of such debt is secured by the assets of the related entities. The carrying value of these guarantees were $1 million at December 31, 2017 and 2016 and the fair values of these guarantees were $1 million at December 31, 2017 and 2016 . The fair value of each guarantee was estimated by comparing the net present value of two hypothetical cash flow streams, one based on PPG’s incremental borrowing rate and the other based on the borrower’s incremental borrowing rate, as of the effective date of the guarantee. Both streams were discounted at a risk free rate of return. The Company does not believe any loss related to these letters of credit, surety bonds or guarantees is likely.

Financial Instruments, Hedging

Financial Instruments, Hedging Activities and Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments, Hedging Activities and Fair Value Measurements	Financial Instruments, Hedging Activities and Fair Value Measurements Financial instruments include cash and cash equivalents, short-term investments, cash held in escrow, marketable equity securities, accounts receivable, company-owned life insurance, accounts payable, short-term and long-term debt instruments, and derivatives. The fair values of these financial instruments approximated their carrying values at December 31, 2017 and 2016 , in the aggregate, except for long-term debt instruments. Hedging Activities The Company has exposure to market risk from changes in foreign currency exchange rates and interest rates and had exposure to PPG’s stock price changes. As a result, financial instruments, including derivatives, have been used to hedge these underlying economic exposures. Certain of these instruments qualify as cash flow, fair value and net investment hedges upon meeting the requisite criteria, including effectiveness of offsetting hedged or underlying exposures. Changes in the fair value of derivatives that do not qualify for hedge accounting are recognized in income from continuing operations in the period incurred. PPG’s policies do not permit speculative use of derivative financial instruments. PPG enters into derivative financial instruments with high credit quality counterparties and diversifies its positions among such counterparties in order to reduce its exposure to credit losses. The Company did not realize a credit loss on derivatives during the three-year period ended December 31, 2017 . All of PPG’s outstanding derivative instruments are subject to accelerated settlement in the event of PPG’s failure to meet its debt or payment obligations under the terms of the instruments’ contractual provisions. In addition, should the Company be acquired and its payment obligations under the derivative instruments’ contractual arrangements not be assumed by the acquirer, or should PPG enter into bankruptcy, receivership or reorganization proceedings, the instruments would also be subject to accelerated settlement. In 2017 and 2016 , there were no derivative instruments de-designated or discontinued as a hedging instrument. There were no gains or losses deferred in AOCI that were reclassified to income from continuing operations during the three-year period ended December 31, 2017 related to hedges of anticipated transactions that were no longer expected to occur. Fair Value Hedges In prior years, PPG designated certain foreign currency forward contracts as hedges against the Company’s exposure to future changes in fair value of certain firm sales commitments denominated in foreign currencies. Prior to June 2016, PPG entered into renewable equity forward arrangements to hedge the impact to PPG's income from continuing operations for changes in the fair value of 2,777,778 shares of PPG stock that were contributed to the asbestos settlement trust as discussed in Note 14, “Commitments and Contingent Liabilities.” These financial instruments were recorded at fair value as assets or liabilities and changes in the fair value of these financial instruments are reflected in the “Asbestos settlement – net” caption of the accompanying consolidated statement of income. The total principal amount paid for these shares was approximately $60 million . During the terms of these equity forward arrangements, PPG paid to the counterparty interest based on the principal amount and the counterparty paid to PPG an amount equal to the dividends paid on these shares which reduced the transaction price by approximately $10 million , net. The difference between the principal amount and any amounts related to unpaid interest or dividends and the market price for these shares, adjusted for credit risk, represented the fair value of these financial instruments as well as the amount that PPG received when the counterparty chose to settle these financial instruments. In conjunction with the funding of the asbestos settlement trust, the equity forward arrangements were settled. At settlement, in June 2016, the fair value of the equity forward arrangement was an asset of $258 million . The Company has used interest rate swaps from time to time to manage it’s exposure to changing interest rates. When outstanding, the interest rate swaps were designated as fair value hedges of certain outstanding debt obligations of the Company and were recorded at fair value. There were no interest rate swaps outstanding as of December 31, 2017 and 2016 . However, in prior years, PPG settled interest rate swaps and received cash. The fair value adjustment of the debt at the time the interest rate swaps were settled is still being amortized as a reduction to interest expense over the remaining term of the related debt, the impact of which is insignificant. Cash Flow Hedges PPG designates certain foreign currency forward contracts as cash flow hedges of the Company’s exposure to variability in exchange rates on intercompany and third party transactions denominated in foreign currencies. As of December 31, 2017 and 2016 , the fair value of all foreign currency forward contracts designated as cash flow hedges was a net asset of $3 million and $13 million , respectively. Net Investment Hedges PPG uses cross currency swaps, foreign currency forward contracts and euro-denominated debt to hedge a significant portion of its net investment in its European operations, as follows: As of December 31, 2017 and 2016 , U.S. dollar to euro cross currency swap contracts with a total notional amount of $560 million were outstanding and are scheduled to expire in March 2018. On settlement of the remaining outstanding contracts, PPG will receive $560 million U.S. dollars and pay euros to the counterparties. During the term of these contracts, PPG receives semiannual payments in March and September of each year based on a U.S. dollar, long-term interest rate fixed as of the contract inception date, and PPG makes annual payments in March of each year to the counterparties based on a euro, long-term interest rate fixed as of the contract inception date. As of December 31, 2017 and 2016 , the fair value of these contracts was an asset of $2 million and $65 million , respectively. At December 31, 2017 and 2016 , PPG had designated €2.3 billion and €2.8 billion , respectively, of euro-denominated borrowings as hedges of a portion of its net investment in the Company’s European operations. The carrying value of these instruments at December 31, 2017 and 2016 was $2.7 billion and $2.9 billion , respectively. During 2017, 2016 and 2015 , PPG used foreign currency forward contracts to hedge a portion of its net investment in its European operations. Changes in the fair value of these derivative instruments were recorded in AOCI as gains or losses. As of December 31, 2017 , 2016 and 2015 , none of these contracts remained outstanding. The Company paid $3 million to settle a foreign currency forward contract in 2017. In 2016, no cash proceeds were received from the settlement of these contracts and, in 2015, PPG received cash proceeds of $19 million from the settlement of these contracts. Other Financial Instruments PPG uses foreign currency forward contracts to manage net transaction exposures that do not qualify for hedge accounting; therefore, the change in the fair value of these instruments is recorded in “Other charges” in the accompanying consolidated statement of income in the period of change. As of December 31, 2017 and 2016, the fair value of these contracts were a liability of $20 million and an asset of $2 million , respectively. Gains/Losses Deferred in AOCI As of December 31, 2017 and 2016 , the Company had accumulated pre-tax unrealized translation gains in AOCI related to the euro-denominated borrowings, foreign currency forward contracts, and the cross currency swaps of $16 million and $482 million , respectively. The following tables summarize the location and amount of gains (losses) related to derivative and debt financial instruments for the years ended December 31, 2017 , 2016 and 2015 . All dollar amounts are shown on a pre-tax basis. 2017 2016 2015 Caption in Consolidated Statement of Income ($ in millions) Loss Deferred in OCI Gain Recognized Gain (Loss) Deferred in OCI (Loss)/Gain Recognized Gain Deferred in OCI (Loss)/Gain Recognized Fair Value Foreign currency forward contracts — — — — — ($2 ) Sales Equity forward arrangements — — — — — (44 ) Asbestos - net Total Fair Value — — — — — ($46 ) Cash Flow Foreign currency forward contracts (a) ($7 ) $9 $1 ($5 ) $57 $50 Other charges and Cost of sales Total Cash Flow ($7 ) $9 $1 ($5 ) $57 $50 Net Investment Cross currency swaps ($61 ) $25 $77 Foreign denominated debt (403 ) 122 85 Foreign currency forward contracts — (14 ) 19 Total Net Investment ($464 ) $133 $181 Economic Foreign currency forward contracts $14 $14 $18 Other charges (a) The ineffective portion related to this item was $7 million , $9 million and $7 million of expense for the years ended December 31, 2017 , 2016 and 2015 , respectively. Fair Value Measurements The Company follows a fair value measurement hierarchy to measure its assets and liabilities. As of December 31, 2017 and 2016 , respectively, the assets and liabilities measured at fair value on a recurring basis were cash equivalents, equity securities and derivatives. In addition, the Company measures its pension plan assets at fair value (see Note 13, “Employee Benefit Plans” for further details). The Company’s financial assets and liabilities are measured using inputs from the following three levels: Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets and liabilities that the Company has the ability to access at the measurement date. Level 1 inputs are considered to be the most reliable evidence of fair value as they are based on unadjusted quoted market prices from various financial information service providers and securities exchanges. Level 2 inputs are directly or indirectly observable prices that are not quoted on active exchanges, which include quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means. The fair values of the derivative instruments reflect the instruments’ contractual terms, including the period to maturity, and uses observable market-based inputs, including forward curves. Level 3 inputs are unobservable inputs employed for measuring the fair value of assets or liabilities. The Company does not have any recurring financial assets or liabilities that are recorded in its consolidated balance sheets as of December 31, 2017 and 2016 that are classified as Level 3 inputs. Assets and liabilities reported at fair value on a recurring basis December 31, 2017 December 31, 2016 ($ in millions) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Other current assets: Marketable equity securities $4 $— — $4 $— — Foreign currency forward contracts — 6 — — 22 — Cross currency swaps — 2 — — — — Other assets: Cross currency swaps — — — — $65 — Investments: Marketable equity securities $79 — — $78 — — Liabilities: Accounts payable and accrued liabilities: Foreign currency forward contracts — $23 — — $9 — Long-Term Debt ($ in millions) December 31, 2017 (a) December 31, 2016 (b) Long-term debt - carrying value $4,123 $4,299 Long-term debt - fair value $4,341 $4,502 (a) Excluding capital lease obligations of $15 million and short term borrowings of $8 million as of December 31, 2017 . (b) Excluding capital lease obligations of $18 million and short term borrowings of $99 million as of December 31, 2016 . The fair values of the debt instruments were based on discounted cash flows and interest rates then currently available to the Company for instruments of the same remaining maturities and were measured using level 2 inputs. Assets and liabilities reported at fair value on a nonrecurring basis There were no significant adjustments to the fair value of nonmonetary assets or liabilities during the year ended December 31, 2017 . In conjunction with the 2016 restructuring actions, certain nonmonetary assets were written down to their fair value. Refer to Note 8, “Business Restructuring” for further details associated with these actions.” Call and put option on noncontrolling interest PPG owns a majority interest in a coatings business whose financial results are included in PPG’s consolidated financial statements. PPG has recorded the noncontrolling interest in this consolidated affiliate as a liability instead of equity in its consolidated balance sheets due to call and put option provisions associated with the noncontrolling interest, which have similar terms. This liability was $44 million and $38 million at December 31, 2017 and 2016 , respectively.

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share (As Restated) ($ in millions, except per share amounts) 2017 2016 2015 As Restated As Restated Earnings per common share (attributable to PPG) Income from continuing operations, net of tax $1,369 $543 $1,311 Income from discontinued operations, net of tax 225 330 95 Net income (attributable to PPG) $1,594 $873 $1,406 Weighted average common shares outstanding 256.1 265.6 271.4 Effect of dilutive securities: Stock options 0.9 0.8 1.0 Other stock compensation plans 0.8 1.0 1.2 Potentially dilutive common shares 1.7 1.8 2.2 Adjusted weighted average common shares outstanding 257.8 267.4 273.6 Earnings per common share (attributable to PPG): Income from continuing operations, net of tax $5.34 $2.05 $4.83 Income from discontinued operations, net of tax 0.88 1.24 0.35 Net income (attributable to PPG) $6.22 $3.29 $5.18 Earnings per common share - assuming dilution (attributable to PPG) Income from continuing operations, net of tax $5.31 $2.04 $4.79 Income from discontinued operations, net of tax 0.87 1.23 0.35 Net income (attributable to PPG) $6.18 $3.27 $5.14 There were 0.6 million outstanding stock options excluded in 2017 , 2016 and 2015 from the computation of earnings per diluted common share due to their anti-dilutive effect.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes (As Restated) The provision for income taxes by taxing jurisdiction and by significant components consisted of the following: ($ in millions) 2017 2016 2015 As Restated As Restated Current U.S. federal $179 ($251 ) $132 U.S. state and local 49 (12 ) 20 Foreign 349 306 261 Total current income tax expense $577 $43 $413 Deferred U.S. federal $107 $173 $31 U.S. state and local (16 ) (10 ) 6 Foreign (53 ) 8 (37 ) Total deferred income tax expense $38 $171 $— Total income tax expense $615 $214 $413 A reconciliation of the statutory U.S. corporate federal income tax rate to the Company’s effective tax rate follows: 2017 2016 2015 As Restated As Restated U.S. federal income tax rate 35.0 % 35.0 % 35.0 % Changes in rate due to: U.S. tax cost - Tax Cuts & Jobs Act 11.0 — — U.S./foreign tax differential (9.3 ) (17.7 ) (8.2 ) U.S. current tax benefit on foreign exchange realization (4.9 ) (3.0 ) — U.S. tax incentives (2.3 ) (3.7 ) (1.9 ) U.S. tax (benefit) cost on foreign dividends (1.9 ) 0.4 (1.0 ) U.S. state and local taxes 1.1 (1.8 ) 1.0 U.S. deferred tax benefit on foreign income (0.6 ) (3.1 ) (4.1 ) Asbestos charge — 19.1 — Other 2.6 2.3 2.9 Effective income tax rate 30.7 % 27.5 % 23.7 % On December 22, 2017, the U.S. enacted the Tax Cuts and Jobs Act (the “Act”) which, among other things lowered the U.S. corporate statutory income tax rate from 35% to 21% , eliminated certain deductible items and added other deductible items for corporations, imposed a tax on unrepatriated foreign earnings and eliminated U.S. taxes on most future foreign earnings. In December 2017, the Company recorded a net tax charge of $134 million related to the Act. The net charge consists of the tax on unrepatriated foreign earnings of approximately $250 million and a charge of approximately $125 million related to the remeasurement of PPG’s U.S. deferred tax assets and liabilities at the new enacted statutory rate. These charges were partially offset by a benefit from the reversal of an existing deferred tax liability on repatriated foreign earnings of approximately $150 million and a benefit resulting from PPG’s decision to accelerate recognition of certain U.S. tax attributes during the fourth quarter. The net charge recorded as a provisional amount as of December 31, 2017 represents the Company’s best estimate using information available as of February 1, 2018. The Company anticipates U.S. regulatory agencies will issue further regulations during 2018, which may alter this estimate. The Company is still evaluating among other things, its position with respect to permanent reinvestment of foreign earnings overseas and other related outside basis difference considerations and the amount of tax owed on unrepatriated earnings by subsidiaries. The Company believes its remeasurement of the U.S deferred tax assets and liabilities is complete, except for changes in estimates that can result from finalizing the filing of our 2017 U.S. income tax return, which are not anticipated to be material, and changes that may be a direct impact of other provisional amounts recorded due to the enactment of the Act. The Company will refine its estimates to incorporate new or better information as it comes available through the filing date of its 2017 U.S. income tax returns in the fourth quarter of 2018. The tax owed by PPG on its unrepatriated foreign earnings is payable over eight years and is subject to a prescriptive calculation to determine the portion payable in 2018 and beyond. PPG’s current estimate, using this prescriptive method, indicates its tax payable will be increased by approximately $1 million to $3 million per year through 2025. As such, the portion of the tax on unrepatriated foreign earnings not payable within the next 12 months is presented within “Other liabilities” on the consolidated balance sheet. The total tax expense for 2017 also includes a deferred tax benefit of $22 million related to the $60 million of pre-tax pension settlement charges discussed in Note 13, “Employee Benefit Plans.” During 2016, the Company recorded a $151 million net tax charge associated with the funding of the Pittsburgh Corning (“PC”) asbestos settlement trust (the “Trust”) described in Note 14, "Commitments and Contingent Liabilities." Further, in conjunction with the funding of the Trust, PPG provided taxes on the earnings of certain foreign subsidiaries and recorded one-time book tax benefits for its contribution of the Company's ownership interest in PC's European subsidiary to the Trust and for a change in the measurement of certain deferred tax liabilities. In 2017 and 2016 , U.S. deferred tax on foreign earnings includes the remeasurement of a U.S. deferred tax liability to repatriate foreign earnings on which PPG has not asserted permanent reinvestment in the foreign jurisdiction. Income (Loss) before income taxes of the Company’s U.S. operations for 2017 , 2016 and 2015 was $713 million , $(210) million and $693 million , respectively. Income before income taxes of the Company’s foreign operations for 2017 , 2016 and 2015 was $1,292 million , $889 million and $1,052 million , respectively. Deferred income taxes Deferred income taxes are provided for the effect of temporary differences that arise because there are certain items treated differently for financial accounting than for income tax reporting purposes. The deferred tax assets and liabilities are determined by applying the enacted tax rate in the year in which the temporary difference is expected to reverse. ($ in millions) 2017 2016 As Restated Deferred income tax assets related to Employee benefits $399 $606 Contingent and accrued liabilities 164 263 Operating loss and other carry-forwards 221 197 Inventories 6 14 Property 51 49 Other 135 100 Valuation allowance (173 ) (119 ) Total $803 $1,110 Deferred income tax liabilities related to Property $314 $349 Intangibles 578 647 Employee benefits 11 4 Derivatives 1 6 Undistributed foreign earnings 24 189 Other 20 146 Total $948 $1,341 Deferred income tax (liabilities) assets – net ($145 ) ($231 ) Net operating loss and credit carryforwards ($ in millions) 2017 2016 Expiration Available net operating loss carryforwards: Indefinite expiration $447 $376 NA Definite expiration 247 118 2018 - 2030 Total $694 $494 NA Net operating loss carryforwards, tax effected $210 $140 NA Income tax credit carryforwards $9 $57 2018 - 2027 A valuation allowance of $170 million and $119 million has been established for carry-forwards at December 31, 2017 and 2016, when the ability to utilize them is not likely. Undistributed foreign earnings The Company had $3.4 billion and $5.3 billion of undistributed earnings of non-U.S. subsidiaries as of December 31, 2017 and 2016, respectively. These amounts relate to approximately 250 subsidiaries in approximately 75 taxable jurisdictions. The Company estimates repatriation of undistributed earnings of non-U.S. subsidiaries as of December 31, 2017 and 2016 would have resulted in a U.S. tax cost of approximately $ 30 million (assuming tax reform) and $ 350 million , respectively. Over the past several years, PPG has established deferred tax liabilities on certain undistributed earnings, namely in connection with divestitures and the funding of the Pittsburgh Corning Asbestos Trust (refer to Note 14, “Commitments and Contingent Liabilities”). At December 31, 2016, the expected future tax cost to repatriate these foreign earnings which were not permanently reinvested totaled $189 million . At December 31, 2016, no significant deferred U.S. income taxes had been provided on the remaining $3.5 billion of PPG’s undistributed earnings as they were considered to be reinvested for an indefinite period of time or will be repatriated when it is tax effective to do so. In 2017, in conjunction with the enactment of the Act, PPG owes U.S. tax on substantially all unrepatriated earnings. As of December 31, 2017, the Company has provisionally not changed its intention to reinvest foreign earnings indefinitely or repatriate when it is tax effective to do so, and as such has not established a liability for foreign withholding taxes or other costs that would be incurred if the earnings were repatriated. Unrecognized tax benefits The Company files federal, state and local income tax returns in numerous domestic and foreign jurisdictions. In most tax jurisdictions, returns are subject to examination by the relevant tax authorities for a number of years after the returns have been filed. The Company is no longer subject to examinations by tax authorities in any major tax jurisdiction for years before 2006. Additionally, the Internal Revenue Service has completed its examination of the Company’s U.S. federal income tax returns filed for years through 2011. The examinations of the Company’s U.S. federal income tax returns for 2012 through 2013 are currently underway. A reconciliation of the total amounts of unrecognized tax benefits (excluding interest and penalties) as of December 31 follows: ($ in millions) 2017 2016 2015 January 1 $94 $82 $71 Current year tax positions - additions 37 25 14 Prior year tax positions - additions 26 8 5 Pre-acquisition unrecognized tax benefits — — 4 Prior year tax positions - reductions — (11 ) (3 ) Statute of limitations expirations (8 ) (8 ) (1 ) Settlements (10 ) — (3 ) Foreign currency translation 9 (2 ) (5 ) December 31 $148 $94 $82 The Company expects that any reasonably possible change in the amount of unrecognized tax benefits in the next 12 months would not be significant. The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate was $140 million as of December 31, 2017 . Interest and penalties ($ in millions) 2017 2016 2015 Accrued interest and penalties related to unrecognized tax benefits $15 $9 $8 Loss recognized in income tax expense related to interest and penalties $4 $1 $2 The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans Defined Benefit Plans PPG has defined benefit pension plans that cover certain employees worldwide. The principal defined benefit pension plans are those in the U.S., Canada, the Netherlands and the U.K. These plans in the aggregate represent approximately 93% of the projected benefit obligation at December 31, 2017 , of which the U.S. defined benefit pension plans represent the largest component. U.S. defined benefit plans As of January 1, 2006, the Company closed the salaried defined benefit plans to new entrants. The defined benefit plan of certain hourly employees was closed to new entrants in 2006 or thereafter. Eligible employees participate in a defined contribution retirement plan. In 2011, the Company approved amendments related to certain U.S. defined benefit plans so that depending upon the affected employee’s combined age and years of service to PPG, certain employees stopped or will stop accruing benefits either during 2011 or in 2020. The affected employees will participate in the Company’s defined contribution retirement plans from the date their benefits under their respective defined benefit plans are frozen. The Company has amended other defined benefit plans in other countries in a similar way and plans to continue reviewing and potentially changing other PPG defined benefit plans in the future. U.S. pension annuity contracts In June 2016, the Company entered into a Definitive Purchase Agreement by and among the Company, Massachusetts Mutual Life Insurance Company (“MassMutual”) and State Street Bank & Trust Company (“State Street”), as independent fiduciary to the Company’s United States defined benefit pension plans (the “Plans”), and a Definitive Purchase Agreement by and among the Company, Metropolitan Life Insurance Company (“MetLife”) and State Street. In August 2016, pursuant to the two Definitive Purchase Agreements, the Plans purchased group annuity contracts that irrevocably transferred to the two insurance companies certain pension benefit obligations for approximately 13,200 of the Company’s retirees in the United States who started receiving their monthly retirement benefit payments on or before April 1, 2016. The value of the benefit obligation of each affected former salaried employee’s retirement benefit obligation is irrevocably guaranteed by, and split equally between, MassMutual and MetLife. Pursuant to these Definitive Purchase Agreements, MassMutual serves as the lead administrator. The value of each affected former hourly employee’s retirement benefit obligation is irrevocably guaranteed by MetLife, and MetLife will serve as the administrator. The amount of each affected retiree’s annuity payment is equal to the amount of such individual’s pension benefit. The purchase of group annuity contracts was funded directly by the assets of the Plans. By irrevocably transferring the obligations and assets to MassMutual and MetLife, the Company reduced its overall pension projected benefit obligation by approximately $1.6 billion and recognized a non-cash pension settlement charge of approximately $535 million after-tax ( $857 million pre-tax). Following the transfer of the aforementioned U.S. retiree obligations and assets to third party insurers, PPG contributed $29 million and $146 million to its U.S. plans in 2017 and 2016, respectively. These contributions were funded using cash on hand. During 2016, as a result of the purchase of group annuity contracts, PPG merged two of its qualified defined benefit pension plans that contained retired plan participants into one surviving plan. In conjunction with the merger and purchase of group annuity contracts, PPG remeasured its qualified pension plan benefit obligations using prevailing discount rates as of July 31, 2016 which averaged 3.6% as compared to a 4.5% discount rate as of December 31, 2015. The remeasurement increased the Company's cumulative pension benefit obligation of its remaining plans by $306 million and increased the Company's full year 2016 qualified defined benefit pension expense by approximately $10 million . Canadian pension annuity contracts In 2016, the Company purchased group annuity contracts that transferred pension benefit obligations for certain of the Company’s retirees and terminated vested participants in Canada who started receiving their monthly retirement benefit payments on or before April 1, 2016 to Sun Life Assurance Company of Canada (“Sun Life”) and The Canada Life Assurance Company (“Canada Life”). The amount of each affected retiree’s annuity payment is equal to the amount of such individual’s pension benefit. The purchase of group annuity contracts was funded directly by the assets of the Canadian plans. By transferring the obligations and assets to Sun Life and Canada Life, the Company reduced its overall pension projected benefit obligation by approximately $200 million and recognized a non-cash pension settlement charge of $47 million after-tax ( $64 million pre-tax). The Company made voluntary contributions aggregating $7 million to the Canadian plans in 2016 related to the pension annuity contracts. These contributions were funded using cash on hand. Sale of the flat glass business In 2016, PPG completed the sale of its flat glass business as discussed in Note 3, “Acquisitions and Divestitures.” PPG transferred to Vitro certain defined benefit pension liabilities resulting in a settlement charge of $11 million which is included in the net gain on the sale of the flat glass business. This transaction lowered the projected benefit obligation of PPG’s defined benefit pension plan by approximately $100 million . PPG transferred pension assets of $55 million in 2016 in connection with the sale and expects to transfer an additional $5 million to $10 million of pension assets in 2018. Sale of the European fiber glass business In 2016, PPG completed the sale of its European fiber glass business as discussed in Note 3, “Acquisitions and Divestitures.” PPG transferred to NEG certain defined benefit pension liabilities resulting in a net settlement charge of $46 million . This amount is included in Income from discontinued operations, net of tax in 2016.This transaction lowered the projected benefit obligation of PPG’s defined benefit pension plans by approximately $340 million . PPG transferred pension assets of approximately $250 million in connection with the sale. Postretirement medical PPG sponsors welfare benefit plans that provide postretirement medical and life insurance benefits for certain U.S. and Canadian employees and their dependents of which the U.S. welfare benefit plans represent approximately 85% of the projected benefit obligation at December 31, 2017. Salaried and certain hourly employees in the U.S. hired on or after October 1, 2004, or rehired on or after October 1, 2012 are not eligible for postretirement medical benefits. The U.S. welfare benefit plans include an Employee Group Waiver Plan (“EGWP”) for certain Medicare-eligible retirees and their dependents which includes a fully-insured Medicare Part D prescription drug plan. As such, PPG is not eligible to receive the federal subsidy provided under the Medicare Act of 2003 for these retirees and their dependents. These plans in the U.S. and Canada require retiree contributions based on retiree-selected coverage levels for certain retirees and their dependents and provide for sharing of future benefit cost increases between PPG and participants based on management discretion. The Company has the right to modify, amend or terminate certain of these benefit plans in the future. In 2016, the Company communicated plan design changes to certain Medicare-eligible retiree plan participants. Effective January 1, 2017, the Company-sponsored Medicare-eligible plans were replaced by a Medicare private exchange. By offering retiree health coverage through a private Medicare exchange, PPG is able to provide Medicare-eligible participants with more choice of plans and plan designs, greater flexibility, and different price points for coverage. Beginning January 1, 2017, PPG’s contribution for health care coverage related to Medicare-eligible retirees is in the form of a tax-free account known as a Health Reimbursement Arrangement (HRA). The HRA can be used to pay for health care and prescription drug plan premiums and certain out-of-pocket medical costs; unused funds can be carried over to future years. The announcement of these plan design changes triggered a remeasurement of PPG’s retiree medical benefit obligation using prevailing interest rates. The plan design change resulted in a $306 million reduction in the Company's postretirement benefit obligation. PPG accounted for the plan design change prospectively, and the plan design change will be amortized to periodic postretirement benefit cost over a 5.6 year period. The following table sets forth the changes in projected benefit obligations (“PBO”) (as calculated as of December 31), plan assets, the funded status and the amounts recognized in the accompanying consolidated balance sheet for the Company’s defined benefit pension and other postretirement benefit plans: Pensions Other Postretirement Benefits ($ in millions) 2017 2016 2017 2016 Projected benefit obligation, January 1 $3,252 $5,349 $792 $1,084 Service cost 33 48 10 15 Interest cost 98 142 24 31 Plan amendments — — — (306 ) Actuarial losses (gains) - net 185 538 (27 ) 13 Benefits paid (167 ) (233 ) (48 ) (53 ) Foreign currency translation adjustments 165 (141 ) 8 2 Settlements and curtailments (85 ) (2,354 ) — — Former glass business changes, net (1 ) (96 ) (8 ) 6 Other (18 ) (1 ) 2 — Projected benefit obligation, December 31 $3,462 $3,252 $753 $792 Market value of plan assets, January 1 $2,561 $4,627 Actual return on plan assets 289 470 Company contributions 87 204 Participant contributions 1 1 Benefits paid (109 ) (205 ) Plan transfers — (3 ) Plan settlements (95 ) (2,338 ) Plan expenses and other-net — — Foreign currency translation adjustments 149 (134 ) Former glass business changes, net — (61 ) Market value of plan assets, December 31 $2,883 $2,561 Funded Status ($579 ) ($691 ) ($753 ) ($792 ) Amounts recognized in the Consolidated Balance Sheet: Other assets (long-term) 173 110 — — Accounts payable and accrued liabilities (23 ) (61 ) (54 ) (61 ) Accrued pensions (729 ) (740 ) — — Other postretirement benefits — — (699 ) (724 ) Liabilities held for sale — — — (7 ) Net liability recognized ($579 ) ($691 ) ($753 ) ($792 ) The PBO is the actuarial present value of benefits attributable to employee service rendered to date, including the effects of estimated future pay increases. The accumulated benefit obligation (“ABO”) is the actuarial present value of benefits attributable to employee service rendered to date, but does not include the effects of estimated future pay increases. The ABO for all defined benefit pension plans as of December 31, 2017 and 2016 was $3,382 million and $3,171 million , respectively. The following table details the pension plans where the benefit liability exceeds the fair value of the plan assets: Pensions ($ in millions) 2017 2016 Plans with PBO in Excess of Plan Assets: Projected benefit obligation $2,544 $2,406 Fair value of plan assets $1,792 $1,609 Plans with ABO in Excess of Plan Assets: Accumulated benefit obligation $2,434 $2,302 Fair value of plan assets $1,749 $1,575 Net actuarial losses and prior service cost/(credit) deferred in accumulated other comprehensive loss ($ in millions) Pensions Other Postretirement Benefits 2017 2016 2017 2016 Accumulated net actuarial losses $835 $918 $180 $226 Accumulated prior service cost (credit) — 1 (239 ) (298 ) Total $835 $919 ($59 ) ($72 ) The accumulated net actuarial losses for pensions and other postretirement benefits relate primarily to historical declines in the discount rate as well as updated mortality assumptions. The accumulated net actuarial losses exceed 10% of the higher of the market value of plan assets or the PBO at the beginning of the year, therefore, amortization of such excess has been included in net periodic benefit costs for pension and other postretirement benefits in each of the last three years. The amortization period is the average remaining service period of active employees expected to receive benefits unless a plan is mostly inactive in which case the amortization period is the average remaining life expectancy of the plan participants. Accumulated prior service cost (credit) is amortized over the future service periods of those employees who are active at the dates of the plan amendments and who are expected to receive benefits. The net decrease in accumulated other comprehensive loss (pre-tax) in 2017 relating to defined benefit pension and other postretirement benefits is primarily attributable to pension settlement charges and other postretirement plan design changes, as follows: ($ in millions) Pensions Other Postretirement Benefits Net actuarial loss (gain) arising during the year $38 ($35 ) New prior service cost (credit) (2 ) 1 Amortization of actuarial loss (75 ) (12 ) Amortization of prior service (cost) credit (1 ) 59 Foreign currency translation adjustments 19 — Impact of settlements and curtailments (63 ) — Net change ($84 ) $13 The 2017 net actuarial loss related to the Company’s pension and other postretirement benefit plans of $3 million was primarily due to a decrease in the weighted average discount rate used to determine the benefit obligation at December 31, 2017, partially offset by asset performance gains in excess of the expected return on plan assets for the year. The estimated amount of accumulated net actuarial loss for the defined benefit pension plans that will be amortized from accumulated other comprehensive income into net periodic benefit cost in 2018 is $68 million . The estimated amounts of accumulated net actuarial loss and prior service (credit) for the other postretirement benefit plans that will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost in 2018 are $17 million and $(60) million , respectively. Net periodic benefit cost Pensions Other Postretirement Benefits ($ in millions) 2017 2016 2015 2017 2016 2015 Service cost $33 $48 $57 $10 $15 $16 Interest cost 98 142 196 24 31 45 Expected return on plan assets (141 ) (213 ) (287 ) — — — Amortization of prior service credit — (1 ) (2 ) (59 ) (31 ) (9 ) Amortization of actuarial losses 75 110 119 12 19 32 Settlements, curtailments, and special termination benefits 60 1,015 8 — — — Net periodic benefit cost/(income) $125 $1,101 $91 ($13 ) $34 $84 Net periodic benefit cost/(income) is included in Cost of sales, exclusive of depreciation and amortization, Selling, general and administrative, Research and development, and Income from discontinued operations, net of tax in the accompanying consolidated statements of income. Key assumptions The following weighted average assumptions were used to determine the benefit obligation for the Company’s defined benefit pension and other postretirement plans as of December 31, 2017 and 2016 : 2017 2016 Discount rate (1) 3.2 % 3.7 % Rate of compensation increase 1.3 % 1.6 % (1) The discount rate for U.S. defined benefit pension and other postretirement plans was 3.7% and 4.3% as of December 31, 2017 and 2016 , respectively. The following weighted average assumptions were used to determine the net periodic benefit cost for the Company’s defined benefit pension and other postretirement benefit plans for the three years in the period ended December 31, 2017 : 2017 2016 2015 Discount rate 3.6 % 3.6 % 3.8 % Expected return on assets 5.4 % 6.1 % 6.1 % Rate of compensation increase 1.3 % 1.6 % 2.0 % These assumptions for each plan are reviewed on an annual basis. In determining the expected return on plan asset assumption, the Company evaluates the mix of investments that comprise each plan’s assets and external forecasts of future long-term investment returns. The Company compares the expected return on plan assets assumption to actual historic returns to ensure reasonability. For 2017, the return on plan assets assumption for PPG’s U.S. defined benefit pension plans was 7.5% . A change in the rate of return of 1 percentage point, with other assumptions held constant, would impact 2017 net periodic pension expense by $11 million . The global expected return on plan assets assumption to be used in determining 2018 net periodic pension expense will be 5.30% ( 7.40% for the U.S. plans only). The discount rate used in accounting for pensions and other postretirement benefits is determined by reference to a current yield curve and by considering the timing and amount of projected future benefit payments. In 2016, the Company changed the method it uses to estimate the service and interest cost components of net periodic benefit cost for pension and other postretirement benefit costs for substantially all of its U.S. and foreign plans. Historically, the service and interest cost components were estimated using a single weighted-average discount rate derived from the yield curve used to measure the projected benefit obligation at the beginning of the period. The Company has elected to use a full yield curve approach (“Split-rate” method) in the estimation of these components of benefit cost by applying specific spot rates along the yield curve used in the determination of the benefit obligation to the relevant projected cash flows. The Company made this change to improve the correlation between projected benefit cash flows and the corresponding yield curve spot rates and to provide a more precise measurement of service and interest costs. This change does not affect the measurement of the Company’s total benefit obligations. The Company accounted for this change as a change in estimate and, accordingly, began recognizing its effect in fiscal year 2016. A change in the discount rate of 1 percentage point, with all other assumptions held constant, would impact 2018 net periodic benefit expense for our defined benefit pension and other postretirement benefit plans by $22 million and $26 million , respectively. In 2017, the Company updated mortality tables used to calculate its U.S. defined benefit pension and other postretirement benefit liabilities. The Company considered the available mortality tables released by the Society of Actuaries’ Retirement Plans Experience Committee and performed a review of its own mortality history, as well the industry in which the Company operates to assess future improvements in mortality rates based on its U.S. population. The Company chose to value its U.S. defined benefit pension and other postretirement benefit liabilities using a slightly modified assumption of future mortality which better approximates our plan participant population. The weighted-average healthcare cost trend rate (inflation) used for 2017 was 6.1% declining to a projected 4.5% in the year 2024 . For 2018 , the assumed weighted-average healthcare cost trend rate used will be 5.8% declining to a projected 4.5% between 2019 and 2039 for medical and prescription drug costs, respectively. These assumptions are reviewed on an annual basis. In selecting rates for current and long-term health care cost assumptions, the Company takes into consideration a number of factors, including the Company’s actual health care cost increases, the design of the Company’s benefit programs, the demographics of the Company’s active and retiree populations and external expectations of future medical cost inflation rates. If these 2018 health care cost trend rates were increased or decreased by one percentage point per year, such increase or decrease would have the following effects: One-Percentage Point ($ in millions) Increase Decrease Increase (decrease) in the aggregate of service and interest cost components of annual expense $1 ($1 ) Increase (decrease) in the benefit obligation $25 ($15 ) Contributions to defined benefit pension plans ($ in millions) 2017 2016 2015 U.S. defined benefit pension plans (a) $54 $134 $224 Non-U.S. defined benefit pension plans (b) $33 $54 $39 (a) During 2016 and 2015, U.S. contributions totaling $12 million and $26 million associated with the former glass segment were recast as cash flows from operations - discontinued operations and are excluded from the table above. (b) During 2016 non-U.S. contributions totaling $4 million associated with the former European fiberglass business were recast as cash flows from operations - discontinued operations and are excluded from the table above. Substantially all contributions made to PPG’s non-U.S. defined benefit pension plans in 2017 and 2016 were required by local funding requirements. PPG expects to make mandatory contributions to its non-U.S. plans in the range of $20 million to $30 million in 2018 . PPG contributed $25 million to its U.S. defined benefit pension plans in January 2018. PPG may make voluntary contributions to its defined benefit pension plans in 2018 and beyond. Benefit payments The estimated benefits expected to be paid under the Company’s defined benefit pension and other postretirement benefit plans are: ($ in millions) Pensions Other Postretirement Benefits 2018 $147 $54 2019 $147 $54 2020 $156 $53 2021 $161 $53 2022 $166 $52 2023 to 2027 $901 $231 U.S. Qualified Pension Beginning in 2012, the Company initiated a lump sum payout program that gave certain terminated vested participants in certain U.S. defined benefit pension plans the option to take a one-time lump sum cash payment in lieu of receiving a future monthly annuity. During 2017, PPG paid $87 million in lump sum benefits to terminated vested participants who elected to participate in the program. As the lump-sum payments were in excess of the expected 2017 service and interest costs for the qualified pension plans, PPG remeasured the periodic benefit obligation of the qualified plans and recorded a settlement charge totaling $35 million ( $22 million after-tax). U.S. Non-qualified Pension In the first quarter 2017, PPG made lump-sum payments to certain retirees who had participated in PPG's U.S. non-qualified pension plan (the "Nonqualified Plan") totaling approximately $40 million . As the lump-sum payments were in excess of the expected 2017 service and interest costs for the Nonqualified Plan, PPG remeasured the periodic benefit obligation of the Nonqualified Plan as of March 1, 2017 and recorded a settlement charge totaling $22 million ( $14 million after-tax). Plan assets Each PPG sponsored defined benefit pension plan is managed in accordance with the requirements of local laws and regulations governing defined benefit pension plans for the exclusive purpose of providing pension benefits to participants and their beneficiaries. Investment committees comprised of PPG managers have fiduciary responsibility to oversee the management of pension plan assets by third party asset managers. Pension plan assets are held in trust by financial institutions and managed on a day-to-day basis by the asset managers. The asset managers receive a mandate from each investment committee that is aligned with the asset allocation targets established by each investment committee to achieve the plan’s investment strategies. The performance of the asset managers is monitored and evaluated by the investment committees throughout the year. Pension plan assets are invested to generate investment earnings over an extended time horizon to help fund the cost of benefits promised under the plans while mitigating investment risk. The asset allocation targets established for each pension plan are intended to diversify the investments among a variety of asset categories and among a variety of individual securities within each asset category to mitigate investment risk and provide each plan with sufficient liquidity to fund the payment of pension benefits to retirees. The following summarizes the weighted average target pension plan asset allocation as of December 31, 2017 and 2016 for all PPG defined benefit plans: Asset Category 2017 2016 Equity securities 15-45% 30-65% Debt securities 30-65% 30-65% Real estate 0-10% 0-10% Other 20-40% 0-20% The fair values of the Company’s pension plan assets at December 31, 2017 and 2016 , by asset category, are as follows: December 31, 2017 December 31, 2016 ($ in millions) Level 1 (1) Level 2 (1) Level 3 (1) Total Level 1 (1) Level 2 (1) Level 3 (1) Total Asset Category Equity securities: U.S. Large cap $— $83 $— $83 $— $80 $— $80 Small cap 29 — — 29 — — — — PPG common stock — — — — 53 — — 53 Non-U.S. Developed and emerging markets (2) 115 79 — 194 80 75 — 155 Debt securities: Cash and cash equivalents — 11 — 11 — 6 — 6 Corporate (3) U.S. (4) — 201 86 287 — 5 86 91 Developed and emerging markets (2) — 43 — 43 — 42 — 42 Diversified (5) — 124 — 124 — 71 — 71 Government U.S. (4) 68 1 — 69 — — — — Developed markets — 101 — 101 — 78 — 78 Other (6) — 14 418 432 — — 15 15 Real estate, hedge funds, and other — 185 498 683 — 172 414 586 Total assets in the fair value hierarchy $212 $842 $1,002 $2,056 $133 $529 $515 $1,177 Common-collective trusts (7) — — — 827 — — — 1,384 Total Investments $212 $842 $1,002 $2,883 $133 $529 $515 $2,561 (1) These levels refer to the accounting guidance on fair value measurement described in Note 10, “Financial Instruments, Hedging Activities and Fair Value Measurements.” (2) These amounts represent holdings in investment grade debt or equity securities of issuers in both developed markets and emerging economies. (3) This category represents investment grade debt securities from a diverse set of industry issuers. (4) These investments are primarily long duration fixed income securities. (5) This category represents commingled funds invested in diverse portfolios of debt securities. (6) This category includes mortgage-backed and asset backed debt securities, municipal bonds and other debt securities including derivatives. (7) Certain investments that are measured at net asset value per share (or its equivalent) are not required to be classified in the fair value hierarchy. The change in the fair value of the Company’s Level 3 pension assets for the years ended December 31, 2017 and 2016 was as follows: ($ in millions) Real Estate Other Debt Securities Hedge Funds and Other Assets Total January 1, 2016 $209 $21 $405 $635 Realized gains 28 1 — 29 Unrealized losses (15 ) — (1 ) (16 ) Transfers (out)/in (88 ) (5 ) 16 (77 ) Foreign currency losses (5 ) (1 ) (50 ) (56 ) December 31, 2016 $129 $16 $370 $515 Realized gains 11 45 3 59 Unrealized losses — — 5 5 Transfers (out)/in (5 ) 355 36 386 Foreign currency loss 3 2 32 37 December 31, 2017 $138 $418 $446 $1,002 Real estate properties are externally appraised at least annually by reputable, independent appraisal firms. Property valuations are also reviewed on a regular basis and are adjusted if there has been a significant change in circumstances related to the property since the last valuation. Other debt securities consist of insurance contracts, which are externally valued by insurance companies based on the present value of the expected future cash flows. Hedge funds consist of a wide range of investments which target a relatively stable investment return. The underlying funds are valued at different frequencies, some monthly and some quarterly, based on the value of the underlying investments. Other assets consist primarily of small investments in private equity funds and senior secured debt obligations of non-investment grade borrowers. Retained liabilities and legacy settlement charges PPG has retained certain liabilities for defined benefit pension and postretirement benefits earned for service up to the date of sale of its former automotive glass and service business for employees who were active as of the divestiture date and for individuals who were retirees of the business as of the divestiture date, totaling $369 million and $342 million at December 31, 2017 and 2016 , respectively, for employees who were active as of the divestiture date and for individuals who were retirees of the business as of the divestiture date. PPG recognized expense of $2 million , $20 million and $17 million related to these obligations in 2017 , 2016 , and 2015 , respectively. There have been multiple PPG facility closures in Canada related to the former automotive glass and services business as well as other PPG businesses. These various plant closures have resulted in partial and full windups, and related settlement charges, of pension plans for various hourly and salary employees employed by these locations. The charges are recorded for the individual plans when a particular windup is approved by the Canadian pension authorities. The Company has made all contributions to the individual plan and has discharged the liability through either lump sum payments to participants or purchasing annuities. During 2016, PPG completed the wind-up of two legacy Canadian plans and recorded after-tax wind-up charges totaling $34 million ( $47 million pre-tax). Cash contributions made in conjunction with these windups were approximately $1 million . The Company recorded a settlement charge of $7 million in 2015 related to legacy plant closures. We expect limited additional settlement charges related to these legacy plant closures; although the Company retains the right to continue to review and potentially change other PPG defined benefit plans in the future. Other Plans Defined contribution plans The Company has defined contribution plans for certain employees in the U.S., China, United Kingdom, Australia, Italy, and other countries. For the years ended December 31, 2017 , 2016 , and 2015 , the Company recognized expense for its defined contribution retirement plans of $57 million , $70 million and $60 million , respectively. The Company’s annual cash contributions to its defined contribution retirement plans approximated the expense recognized in each year. As of December 31, 2017 and 2016 , the Company’s obligation for contributions to be made to its defined contribution retirement plans was $15 million and $11 million , respectively. Employee savings plan PPG’s Employee Savings Plan (“Savings Plan”) covers substantially all employees in the U.S., Puerto Rico and Canada. The Company makes matching contributions to the Savings Plan, at management’s discretion, based upon participants’ savings, subject to certain limitations. For most participants not covered by a collective bargaining agreement, Company-matching contributions are established each year at the discretion of the Company and are applied to participant savings up to a maximum of 6% of eligible participant compensation. For those participants whose employment is covered by a collective bargaining agreement, the level of Company-matching contribution, if any, is determined by the relevant collective bargaining agreement. The Company-matching contribution remained at 100% for 2017 . In 2016, the Company terminated its U.S. defined contribution plan and subsequently merged the plan into the Savings Plan. Under the combined plan, eligible employees will continue to receive a contribution equal to between 2% and 5% of annual compensation, based on age and years of service. Compensation expense and cash contributions related to the Company match of participant contributions to the Savings Plan for 2017 , 2016 , and 2015 totaled $46 million , $48 million and $44 million , respectively. A portion of the Savings Plan qualifies under the Internal Revenue Code as an Employee Stock Ownership Plan. Accordingly, dividends received on PPG shares held in that portion of the Savings Plan totaling $14 million , $14 million and $13 million for 2017 , 2016 , and 2015 , respectively, are deductible for U.S. Federal tax purposes. Deferred compensation plan The Company has a deferred compensation plan for certain key managers which allows them to defer a portion of their compensation in a phantom PPG stock account or other phantom investment accounts. The amount deferred earns a return based on the investment options selected by the participant. The amount owed to participants is an unfunded and unsecured general obligation of the Company. Upon retirement, death, disability, termination of employment, scheduled payment or unforeseen emergency, the compensation deferred and related accumulated earnings are distributed in accordance with the participant’s election in cash or in PPG stock, based on the accounts selected by the participant. The plan provides participants with investment alternatives and the ability to transfer amo

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Commitments and Contingent Liabilities PPG is involved in a number of lawsuits and claims, both actual and potential, including some that it has asserted against others, in which substantial monetary damages are sought. These lawsuits and claims may relate to contract, patent, environmental, product liability, antitrust, employment and other matters arising out of the conduct of PPG’s current and past business activities. To the extent that these lawsuits and claims involve personal injury and property damage, PPG believes it has adequate insurance; however, certain of PPG’s insurers are contesting coverage with respect to some of these claims, and other insurers, as they had prior to the asbestos settlement described below, may contest coverage with respect to some of the asbestos claims if the settlement is not implemented. PPG’s lawsuits and claims against others include claims against insurers and other third parties with respect to actual and contingent losses related to environmental, asbestos and other matters. The results of any current or future litigation and claims are inherently unpredictable. However, management believes that, in the aggregate, the outcome of all lawsuits and claims involving PPG will not have a material effect on PPG’s consolidated financial position or liquidity; however, such outcome may be material to the results of operations of any particular period in which costs, if any, are recognized. Asbestos matters Prior to 2000, the Company had been named as a defendant in numerous claims alleging bodily injury from (i) exposure to asbestos-containing products allegedly manufactured, sold or distributed by the Company, its subsidiaries, or for which they are otherwise alleged to be liable; (ii) exposure to asbestos allegedly present at a facility owned or leased by the Company; or (iii) exposure to asbestos-containing products of Pittsburgh Corning Corporation (“PC”) for which the Company was alleged to be liable under a variety of legal theories (the Company and Corning Incorporated were each 50% shareholders in PC). Pittsburgh Corning Corporation asbestos bankruptcy In 2000, PC filed for Chapter 11 in the U.S. Bankruptcy Court for the Western District of Pennsylvania in an effort to permanently and comprehensively resolve all of its pending and future asbestos-related liability claims. At the time of the bankruptcy filing, the Company had been named as one of many defendants in approximately 114,000 open claims. The Bankruptcy Court subsequently entered a series of orders preliminarily enjoining the prosecution of asbestos litigation against PPG until after the effective date of a confirmed PC plan of reorganization. During the pendency of this preliminary injunction staying asbestos litigation against PPG, PPG and certain of its historical liability insurers negotiated a settlement with representatives of present and future asbestos claimants. That settlement was incorporated into a PC plan of reorganization that was confirmed by the Bankruptcy Court on May 24, 2013 and ultimately became effective on April 27, 2016. With the effectiveness of the plan, the preliminary injunction staying the prosecution of asbestos litigation against PPG expired by its own terms on May 27, 2016. In accordance with the settlement, the Bankruptcy Court issued a permanent channeling injunction under Section 524(g) of the Bankruptcy Code that prohibits present and future claimants from asserting claims against PPG that arise, in whole or in part, out of exposure to asbestos or asbestos-containing products manufactured, sold and/or distributed by PC or asbestos on or emanating from any PC premises. The channeling injunction, by its terms, also prohibits codefendants in cases that are subject to the channeling injunction from asserting claims against PPG for contribution, indemnification or other recovery. The channeling injunction also precludes the prosecution of claims against PPG arising from alleged exposure to asbestos or asbestos-containing products to the extent that a claimant is alleging or seeking to impose liability, directly or indirectly, for the conduct of, claims against, or demands on PC by reason of PPG’s: (i) ownership of a financial interest in PC; (ii) involvement in the management of PC, or service as an officer, director or employee of PC or a related party; (iii) provision of insurance to PC or a related party; or (iv) involvement in a financial transaction affecting the financial condition of PC or a related party. The foregoing PC related claims are referred to as “PC Relationship Claims.” The channeling injunction channels the Company’s liability for PC Relationship Claims to a trust funded in part by PPG and its participating insurers for the benefit of current and future PC asbestos claimants (the “Trust”). The Trust is the sole recourse for holders of PC Relationship Claims. PPG and its affiliates have no further liability or responsibility for, and will be permanently protected from, pending and future PC Relationship Claims. The channeling injunction does not extend to present and future claims against PPG that arise out of alleged exposure to asbestos or asbestos-containing products historically manufactured, sold and/or distributed by PPG or its subsidiaries or for which they are alleged to be liable that are not PC Relationship Claims, and does not extend to claims against PPG alleging personal injury allegedly caused by asbestos on premises presently or formerly owned, leased or occupied by PPG. These claims are referred to as non-PC Relationship Claims. In accordance with the PC plan of reorganization, PPG's equity interest in PC was canceled. PPG satisfied its funding obligations to the Trust on June 9, 2016, when it conveyed to the Trust the stock it owned in Pittsburgh Corning Europe and 2,777,778 shares of PPG’s common stock and made a cash payment to the Trust in the amount of $764 million . PPG’s historical insurance carriers participating in the PC plan of reorganization are required to make cash payments to the Trust of approximately $1.7 billion , subject to a right of prepayment at a 5.5% discount rate. On October 13, 2016, the Bankruptcy Court issued an order entering a final decree and closing the Chapter 11 case. That order provided that the Bankruptcy Court retained jurisdiction to enforce any order issued in the case and any agreements approved by the court, enforce the terms and conditions or the modified third amended Plan, and consider any requests to reopen the case. The following table outlines the impact on PPG's financial statements for the year-ended December 31, 2016, including the change in fair value of the PPG stock contributed to the Trust, the equity forward instrument and the increase in the net present value of the payments made to the trust. Consolidated Balance Sheet Asbestos Settlement Liability Equity Forward (Asset) Liability Pre-tax Charge ($ in millions) Current Long-term Balance as of and Activity for the year ended December 31, 2015 $796 $252 ($223 ) $12 Change in fair value: PPG stock 34 — — 34 Equity forward instrument — (35 ) (35 ) Accretion of asbestos liability — 6 — 6 Settlement of equity forward instrument with counterparty (a) — — (49 ) — Contribution of PCE shares and relinquishment of PC investment (15 ) — — — Contribution of 2,777,778 shares of PPG stock to the PC Trust (308 ) 308 Contribution of cash to the PC Trust (a) (506 ) (258 ) — Reclassification (1 ) — (1 ) — Balance as of and Activity for the year ended December 31, 2016 $— $— $— $5 (a) Cash outflows related to the asbestos settlement funding totaled $813 million in 2016. Non-PC relationship asbestos claims At the time PC filed for bankruptcy, PPG had been named as one of many defendants in one or more of the categories of asbestos-related claims identified above. Over the course of the 16 years during which the PC bankruptcy proceedings, and corresponding preliminary injunction staying the prosecution of asbestos-related claims against PPG, were pending, certain plaintiffs alleging premises claims filed motions seeking to lift the stay with respect to more than 1,000 individually-identified premises. The Bankruptcy Court granted motions to lift the stay in respect to certain of these premises claims and directed PPG to engage in a process to address any additional premises claims that were the subject of pending or anticipated lift-stay motions. As a result of the overall process as directed by the Bankruptcy Court involving more than 1,000 premises claims between 2006 and May 27, 2016, hundreds of these claims were withdrawn or dismissed without payment and approximately 650 premises claims were dismissed upon agreements by PPG and its insurers to resolve such claims in exchange for monetary payments. With respect to the remaining claims not identified above and still reportable within the inventory of 114,000 asbestos-related claims at the time PC filed for bankruptcy, the Company considers such claims to fall within one or more of the following categories: (1) claims that have been closed or dismissed as a result of processes undertaken during the bankruptcy; (2) claims that may have been previously filed on the dockets of state and federal courts in various jurisdictions, but are inactive as to the Company; and (3) claims that are subject, in whole or in part, to the channeling injunction and thus will be resolved, in whole or in part, in accordance with the Trust procedures established under the PC bankruptcy reorganization plan. As a result of the foregoing, the Company does not consider these three categories of claims to be open or active litigation against it, although the Company cannot now determine whether, or the extent to which, any of these claims may in the future be reinstituted, reinstated, or revived such that they may become open and active asbestos-related claims against it. Current open and active claims post-Pittsburgh Corning bankruptcy The Company is aware of approximately 625 open and active asbestos-related claims pending against the Company and certain of its subsidiaries. These claims consist primarily of non-PC Relationship Claims and claims against a subsidiary of PPG. The Company is defending the remaining open and active claims vigorously. Since April 1, 2013, a subsidiary of PPG has been implicated in claims alleging death or injury caused by asbestos-containing products manufactured, distributed or sold by a North American architectural coatings business or its predecessors which was acquired by PPG. All such claims have been either served upon or tendered to the seller for defense and indemnity pursuant to obligations undertaken by the seller in connection with the Company’s purchase of the North American architectural coatings business. The seller has accepted the defense of these claims subject to the terms of various agreements between the Company and the seller. The seller’s defense and indemnity obligations in connection with newly filed claims will cease with respect to claims filed after April 1, 2018. PPG has established reserves totaling approximately $180 million for asbestos-related claims that would not be channeled to the Trust which, based on presently available information, we believe will be sufficient to encompass all of PPG’s current and potential future asbestos liabilities. These reserves include a $162 million reserve established in 2009 in connection with an amendment to the PC plan of reorganization. These reserves, which are included within "Other liabilities" on the accompanying consolidated balance sheets, represent PPG’s best estimate of its liability for these claims. PPG does not have sufficient current claim information or settlement history on which to base a better estimate of this liability in light of the fact that the Bankruptcy Court’s injunction staying most asbestos claims against the Company was in effect from April 2000 through May 2016. PPG will monitor the activity associated with its remaining asbestos claims and evaluate, on a periodic basis, its estimated liability for such claims, its insurance assets then available, and all underlying assumptions to determine whether any adjustment to the reserves for these claims is required. The amount reserved for asbestos-related claims by its nature is subject to many uncertainties that may change over time, including (i) the ultimate number of claims filed; (ii) the amounts required to resolve both currently known and future unknown claims; (iii) the amount of insurance, if any, available to cover such claims; (iv) the unpredictable aspects of the litigation process, including a changing trial docket and the jurisdictions in which trials are scheduled; (v) the outcome of any trials, including potential judgments or jury verdicts; (vi) the lack of specific information in many cases concerning exposure for which PPG is allegedly responsible, and the claimants’ alleged diseases resulting from such exposure; and (vii) potential changes in applicable federal and/or state tort liability law. All of these factors may have a material effect upon future asbestos-related liability estimates. As a potential offset to any future asbestos financial exposure, under the PC plan of reorganization PPG retained, for its own account, the right to pursue insurance coverage from certain of its historical insurers that did not participate in the PC plan of reorganization. While the ultimate outcome of PPG’s asbestos litigation cannot be predicted with certainty, PPG believes that any financial exposure resulting from its asbestos-related claims will not have a material adverse effect on PPG’s consolidated financial position, liquidity or results of operations. Environmental matters It is PPG’s policy to accrue expenses for environmental contingencies when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. Reserves for environmental contingencies are exclusive of claims against third parties and are generally not discounted. In management’s opinion, the Company operates in an environmentally sound manner and the outcome of the Company’s environmental contingencies will not have a material effect on PPG’s financial position or liquidity; however, any such outcome may be material to the results of operations of any particular period in which costs, if any, are recognized. Management anticipates that the resolution of the Company’s environmental contingencies will occur over an extended period of time. As of December 31, 2017 and 2016 , PPG had reserves for environmental contingencies associated with PPG’s former chromium manufacturing plant in Jersey City, N.J. (“New Jersey Chrome”) and for other environmental contingencies, including National Priority List sites and legacy glass and chemical manufacturing sites. These reserves are reported as “Accounts payable and accrued liabilities” and “Other liabilities” in the accompanying consolidated balance sheet. Environmental Reserves ($ in millions) 2017 2016 New Jersey Chrome $136 $163 Legacy glass and chemical 71 70 Other 51 52 Total $258 $285 Current Portion $73 $76 Pre-tax charges against income for environmental remediation costs are included in “Other charges” in the accompanying consolidated statement of income. The pre-tax charges and cash outlays related to such environmental remediation in 2017 , 2016 and 2015 , were as follows: ($ in millions) 2017 2016 2015 New Jersey Chrome $4 $60 $— Other 6 34 9 Total $10 $94 $9 Cash outlays for environmental spending $44 $47 $109 The Company continues to analyze, assess and remediate the environmental issues associated with New Jersey Chrome as further discussed below. During the past three years, charges for estimated environmental remediation costs were significantly higher than PPG’s historical range. Excluding the charges related to New Jersey Chrome, pre-tax charges against income for environmental remediation have ranged between approximately $5 million and $35 million per year for the past 10 years. Management expects cash outlays for environmental remediation costs to range from $25 million to $75 million annually from 2018 through 2022. It is possible that technological, regulatory and enforcement developments, the results of environmental studies and other factors could alter the Company’s expectations with respect to future charges against income and future cash outlays. Specifically, the level of expected future remediation costs and cash outlays is highly dependent upon activity related to New Jersey Chrome as discussed below. Remediation: New Jersey Chrome In June 2009, PPG entered into a settlement agreement with the New Jersey Department of Environmental Protection (“NJDEP”) and Jersey City, New Jersey (which had asserted claims against PPG for lost tax revenue) which was in the form of a Judicial Consent Order (the "JCO"). Under the JCO, PPG accepted sole responsibility for the remediation activities at its former chromium manufacturing location in Jersey City and 19 additional sites. The principal contaminant of concern is hexavalent chromium. The JCO also provided for the appointment of a court-approved Site Administrator who is responsible for establishing a master schedule for the remediation of the 20 PPG sites which existed at that time. One site was subsequently removed from the JCO process during 2014 and will be remediated separately at a future date. A total of 19 sites remain subject to the JCO process. The most significant assumptions underlying the estimate of remediation costs for all New Jersey Chrome sites are those related to the extent and concentration of chromium impacts in the soil, as these determine the quantity of soil that must be treated in place, the quantity that will have to be excavated and transported for offsite disposal, and the nature of disposal required. During 2016, PPG completed updated assessments of costs incurred to date versus current progress and the potential cost impacts of the most recent information, including the extent of impacted soils, percentage of hazardous versus non-hazardous soils, daily soil excavation rates, and engineering, administrative and other associated costs. Based on these assessments, a reserve adjustment of $60 million was recorded during 2016. Principal factors affecting costs included refinements in the estimate of the mix of hazardous to non-hazardous soils to be excavated, an overall increase in soil volumes to be excavated, enhanced water management requirements, decreased daily soil excavation rates due to site conditions, initial estimates for remedial actions related to groundwater, and increased oversight and management costs. The reserve adjustments for the estimated costs to remediate all New Jersey Chrome sites are exclusive of any third party indemnification, as the recovery of any such amounts is uncertain. In 2017, the cost of remediation activities reduced the reserve by $27 million . Groundwater remediation at the former Garfield Avenue chromium-manufacturing site and five adjacent sites is expected to occur over several years after NJDEP’s approval of the work plan. Ongoing groundwater monitoring will be utilized to develop a final groundwater remedial action work plan which is currently expected to be submitted to NJDEP in 2021. PPG’s financial reserve for remediation of all New Jersey Chrome sites is $136 million at December 31, 2017 . The major cost components of this liability continue to be related to excavation, transportation and disposal of impacted soil, as well as construction services. These components each account for approximately 29% , 27% and 23% of the accrued amount, respectively. There are multiple, future events yet to occur, including further remedy selection and design, remedy implementation and execution and applicable governmental agency or community organization approvals. Considerable uncertainty exists regarding the timing of these future events for the New Jersey Chrome sites. Final resolution of these events is expected to occur over the next several years. As these events occur and to the extent that the cost estimates of the environmental remediation remedies change, the existing reserve for this environmental remediation matter will be adjusted. Remediation: other sites Among other sites at which PPG is managing environmental liabilities, remedial actions are occurring at a legacy chemical manufacturing site in Barberton, Ohio, where PPG has completed a Facility Investigation and Corrective Measure Study under USEPA’s Resource Conservation and Recovery Act (“RCRA”) Corrective Action Program. PPG has also been addressing the impacts from a legacy plate glass manufacturing site in Kokomo, Indiana under the Voluntary Remediation Program of the Indiana Department of Environmental Management. PPG is currently performing additional investigation activities at this location. With respect to certain other waste sites, the financial condition of other potentially responsible parties also contributes to the uncertainty of estimating PPG’s final costs. Although contributors of waste to sites involving other potentially responsible parties may face governmental agency assertions of joint and several liability, in general, final allocations of costs are made based on the relative contributions of wastes to such sites. PPG is generally not a major contributor to such sites. Separation and merger of the commodity chemicals business As a result of the commodity chemicals business separation transaction in 2013, PPG has retained responsibility for potential environmental liabilities that may result from future Natural Resource Damage claims and any potential tort claims at the Calcasieu River Estuary associated with activities and historical operations of the Lake Charles, La. facility. In the fourth quarter of 2017, PPG signed a consent decree prepared by the US Department of Justice for settlement of potential natural resource damage claims at the Calcasieu River Estuary. Payment of PPG’s previously accrued for share of costs into an escrow account will be required within 30 days of lodging of the agreement with the court. Lodging is expected to occur in the first quarter of 2018. PPG retained additional responsibility for all liabilities relating to, arising out of or resulting from sediment contamination in the Ohio River resulting from historical activities and operations at the Natrium, W.Va. facility, exclusive of remedial activities, if any, that would have been required to have been performed on-site at the Natrium facility. PPG’s obligations with respect to the Ohio River sediment contamination terminated because PPG received no notice of any requirements to further assess or to remediate sediment contamination in the Ohio River, caused by PPG’s operation of the Natrium facility prior to the separation of the commodity chemicals business, during an indemnification period established in the agreement transferring the business to Axiall that ended on December 30, 2017. Remediation: reasonably possible matters In addition to the amounts currently reserved for environmental remediation, the Company may be subject to loss contingencies related to environmental matters estimated to be as much as $100 million to $200 million . Such unreserved losses are reasonably possible but are not currently considered to be probable of occurrence. These reasonably possible unreserved losses relate to environmental matters at a number of sites, none of which are individually significant. The loss contingencies related to these sites include significant unresolved issues such as the nature and extent of contamination at these sites and the methods that may have to be employed to remediate them. The impact of evolving programs, such as natural resource damage claims, industrial site re-use initiatives and domestic and international remediation programs, also adds to the present uncertainties with regard to the ultimate resolution of this unreserved exposure to future loss. The Company’s assessment of the potential impact of these environmental contingencies is subject to considerable uncertainty due to the complex, ongoing and evolving process of investigation and remediation, if necessary, of such environmental contingencies, and the potential for technological and regulatory developments.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity A class of 10 million shares of preferred stock, without par value, is authorized but unissued. Common stock has a par value of $1.66 2 / 3 per share; 1.2 billion shares are authorized. Common Stock Treasury Stock Shares Outstanding January 1, 2015 581,146,136 (309,181,570 ) 271,964,566 Purchases — (6,992,772 ) (6,992,772 ) Issuances — 1,904,215 1,904,215 December 31, 2015 581,146,136 (314,270,127 ) 266,876,009 Purchases — (10,725,869 ) (10,725,869 ) Issuances — 1,180,020 1,180,020 December 31, 2016 581,146,136 (323,815,976 ) 257,330,160 Purchases — (7,427,557 ) (7,427,557 ) Issuances — 1,271,796 1,271,796 December 31, 2017 581,146,136 (329,971,737 ) 251,174,399 Per share cash dividends paid were $1.70 in 2017 , $1.56 in 2016 and $1.41 in 2015 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss ($ in millions) Unrealized Foreign Currency Translation Adjustments Pension and Other Postretirement Benefit Adjustments, net of tax (c) Unrealized Gain (Loss) on Derivatives, net of tax (d) Accumulated Other Comprehensive (Loss) Income January 1, 2015 ($628 ) ($1,492 ) $4 ($2,116 ) Current year deferrals to AOCI (a) (630 ) — — (630 ) Current year deferrals to AOCI, tax effected (b) (74 ) 9 41 (24 ) Reclassifications from AOCI to net income — 104 (36 ) 68 Period change ($704 ) $113 $5 ($586 ) December 31, 2015 ($1,332 ) ($1,379 ) $9 ($2,702 ) Current year deferrals to AOCI (a) (299 ) — — (299 ) Current year deferrals to AOCI, tax effected (b) (167 ) 29 3 (135 ) Reclassifications from AOCI to net income — 779 1 780 Period change ($466 ) $808 $4 $346 December 31, 2016 ($1,798 ) ($571 ) $13 ($2,356 ) Current year deferrals to AOCI (a) 542 — — 542 Current year deferrals to AOCI, tax effected (b) (311 ) 20 (4 ) (295 ) Reclassifications from AOCI to net income 58 (6 ) 52 Period change 231 78 (10 ) 299 December 31, 2017 ($1,567 ) ($493 ) $3 ($2,057 ) (a) Unrealized foreign currency translation adjustments related to translation of foreign denominated balance sheets are not presented net of tax given that no deferred U.S. income taxes have been provided on undistributed earnings of non-U.S. subsidiaries because they are deemed to be reinvested for an indefinite period of time. (b) The tax benefit (cost) related to unrealized foreign currency translation adjustments on tax inter-branch transactions and net investment hedges for the years ended December 31, 2017 , 2016 and 2015 was $141 million , $(34) million and $(84) million , respectively. In 2015, the balance includes a remeasurement of the tax cost on the foreign proceeds from the sale of the Company’s interest in Transitions Optical which have not been permanently reinvested. Refer to Note 3, “Acquisitions and Divestitures” for additional information. (c) The tax cost related to the adjustment for pension and other postretirement benefits for the years ended December 31, 2017 , 2016 and 2015 was $(33) million , $(403) million and $(51) million , respectively. Reclassifications from AOCI are included in the computation of net periodic benefit costs (See Note 13, “Employee Benefit Plans”). The cumulative tax benefit related to the adjustment for pension and other postretirement benefits at December 31, 2017 and 2016 was $243 million and $276 million , respectively. (d) The tax cost (benefit) related to the change in the unrealized gain on derivatives for the years ended December 31, 2017 , 2016 and 2015 was $5 million , $2 million and $(2) million , respectively. Reclassifications from AOCI are included in the gain or loss recognized on cash flow hedges (See Note 10 “Financial Instruments, Hedging Activities and Fair Value Measurements”).

Other Income

Other Income	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Other Earnings	Other Income (As Restated) ($ in millions) 2017 2016 2015 As Restated As Restated Gain on disposals of ownership interests in business affiliates $25 $46 $— Royalty income 11 12 15 Share of net earnings of equity affiliates (See Note 6) 12 8 4 Gain on sale of assets 28 6 4 Income from a legal settlement 18 — — Other 56 55 87 Total $150 $127 $110

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation (As Restated) The Company’s stock-based compensation includes stock options, restricted stock units (“RSUs”) and grants of contingent shares that are earned based on achieving targeted levels of total shareholder return. All current grants of stock options, RSUs and contingent shares are made under the PPG Industries, Inc. Amended and Restated Omnibus Incentive Plan (“PPG Amended Omnibus Plan”), which was amended and restated effective April 21, 2016. Shares available for future grants under the PPG Amended Omnibus Plan were 8.0 million as of December 31, 2017 . ($ in millions) 2017 2016 2015 As Restated As Restated Total stock-based compensation $35 $45 $54 Income tax benefit recognized $12 $17 $18 Stock Options PPG has outstanding stock option awards that have been granted under the PPG Amended Omnibus Plan. Under the PPG Amended Omnibus Plan, certain employees of the Company have been granted options to purchase shares of common stock at prices equal to the fair market value of the shares on the date the options were granted. The options are generally exercisable 36 months after being granted and have a maximum term of 10 years. Upon exercise of a stock option, shares of Company stock are issued from treasury stock. The fair value of stock options issued to employees is measured on the date of grant and is recognized as expense over the requisite service period. PPG estimates the fair value of stock options using the Black-Scholes option pricing model. The risk-free interest rate is determined by using the U.S. Treasury yield curve at the date of the grant and using a maturity equal to the expected life of the option. The expected life of options is calculated using the average of the vesting term and the maximum term, as prescribed by accounting guidance on the use of the simplified method for determining the expected term of an employee share option. The expected dividend yield and volatility are based on historical stock prices and dividend amounts over past time periods equal in length to the expected life of the options. The following weighted average assumptions were used to calculate the fair values of stock option grants in each year: 2017 2016 2015 Weighted average exercise price $101.53 $95.29 $118.02 Risk free interest rate 2.4 % 1.6 % 1.9 % Expected life of option in years 6.5 6.5 6.5 Expected dividend yield 1.8 % 2.1 % 2.7 % Expected volatility 22.0 % 22.8 % 29.2 % The weighted average fair value of options granted was $21.15 per share, $17.94 per share and $26.94 per share for the years ended December 31, 2017 , 2016 , and 2015 , respectively. Stock Options Outstanding and Exercisable Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Intrinsic Value (in millions) Outstanding, January 1, 2016 3,881,566 $75.84 6.5 $86 Granted 642,037 $101.53 Exercised (856,900 ) $61.10 Forfeited/Expired (91,078 ) $101.36 Outstanding, December 31, 2017 3,575,625 $83.34 6.4 $120 Vested or expected to vest, December 31, 2017 3,530,023 $83.05 6.4 $120 Exercisable, December 31, 2017 1,677,087 $60.13 4.4 $95 At December 31, 2017 , unrecognized compensation cost related to outstanding stock options that have not yet vested totaled $7 million . This cost is expected to be recognized as expense over a weighted average period of 1.5 years. The following table presents stock option activity for the years ended December 31, 2017 , 2016 and 2015 : ($ in millions) 2017 2016 2015 Total intrinsic value of stock options exercised $40 $34 $92 Cash received from stock option exercises $52 $32 $53 Income tax benefit from the exercise of stock options $15 $12 $31 Total fair value of stock options vested $13 $16 $13 Restricted Stock Units (“RSUs”) Long-term incentive value is delivered to selected key management employees by granting RSUs, which have either time or performance-based vesting features. The fair value of an RSU is equal to the market value of a share of PPG stock on the date of grant. Time-based RSUs vest over the three -year period following the date of grant, unless forfeited, and will be paid out in the form of stock, cash or a combination of both at the Company’s discretion at the end of the three year vesting period. Performance-based RSUs vest based on achieving specific annual performance targets for earnings per share growth and cash flow return on capital over the three calendar year-end periods following the date of grant. Unless forfeited, the performance-based RSUs will be paid out in the form of stock, cash or a combination of both at the Company’s discretion at the end of the three -year performance period if PPG meets the performance targets. The amount paid for performance-based awards may range from 0% to 180% of the original grant, based upon the frequency with which the annual earnings per share growth and cash flow return on capital performance targets are met over the three calendar year periods comprising the vesting period. For the purposes of expense recognition, PPG has assumed that performance-based RSUs granted in 2015 will vest at the 150% level and those granted in 2016 and 2017 will vest at the 100% level. As of December 31, 2017 , four of the six possible performance targets had been met for the 2015 grant, two of the four possible performance targets had been met for the 2016 grant, and one of two possible performance targets had been met for the 2017 grant. RSU Activity Number of Shares Weighted Average Fair Value Intrinsic Value (in millions) Outstanding, January 1, 2017 721,924 $95.65 $69 Granted 229,667 $102.71 Additional shares vested 70,525 $114.08 Released from restrictions (349,871 ) $103.09 Forfeited (56,638 ) $89.16 Outstanding, December 31, 2017 615,607 $101.73 $63 Vested or expected to vest, December 31, 2017 595,462 $101.89 $60 There was $14 million of total unrecognized compensation cost related to unvested RSUs outstanding as of December 31, 2017 . This cost is expected to be recognized as expense over a weighted average period of 1.7 years. Contingent Share Grants The Company also provides grants of contingent shares to selected key executives that may be earned based on PPG total shareholder return (“TSR”) over the three -year period following the date of grant. Contingent share grants (referred to as “TSR awards”) are made annually and are paid out at the end of each three -year period based on the Company’s performance. Performance is measured by determining the percentile rank of the total shareholder return of PPG common stock in relation to the total shareholder return of the S&P 500 for the three -year period following the date of grant. This comparison group represents the entire S&P 500 Index as it existed at the beginning of the performance period, excluding any companies that have been removed from the index because they ceased to be publicly traded. The payment of awards following the three -year award period will be based on performance achieved in accordance with the scale set forth in the plan agreement and may range from 0% to 220% of the initial grant. A payout of 100% is earned if the target performance is achieved. Contingent share awards for the 2015-2017, 2016-2018, and 2017-2019 periods earn dividend equivalents for the award period, which will be paid to participants or credited to the participants’ deferred compensation plan accounts with the award payout at the end of the period based on the actual number of contingent shares that are earned. Any payments made at the end of the award period may be in the form of stock, cash or a combination of both. The TSR awards qualify as liability awards, and compensation expense is recognized over the three -year award period based on the fair value of the awards (giving consideration to the Company’s percentile rank of total shareholder return) remeasured in each reporting period until settlement of the awards. As of December 31, 2017 , there was $3 million of total unrecognized compensation cost related to outstanding TSR awards based on the current estimate of fair value. This cost is expected to be recognized as expense over a weighted average period of 1.7 years.

Quarterly Financial Information

Quarterly Financial Information (unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (unaudited)	Quarterly Financial Information (unaudited) (As Restated) As further described in the Explanatory Note, in lieu of filing amended quarterly reports on Form 10-Q for 2017 and 2016, quarterly financial data for 2017 and 2016 (As Restated) is included in this Annual Report in the tables that follow. The following provides the condensed consolidated financial statements and notes (unaudited) as restated for the three months ended December 31, 2016 and the three months ended March 31, 2017, June 30, 2017 (and the six months ended), September 30, 2017 (and the nine months ended) and December 31, 2017. In addition to the restatement of the financial statements, certain information within the following notes to the financial statements and financial statement schedule has been restated to reflect the corrections of misstatements discussed previously: Acquisitions and Divestitures Stock-based Compensation Shareholders’ Equity Reportable Business Segment Information Impact of the Restatement As a result of the restatement, reported net income from continuing operations and earnings per diluted share from continuing operations was adjusted for the appropriate quarterly periods within 2016 and 2017 as follows: • For the quarter ended December 31, 2016, net income from continuing operations decreased $4 million , or $0.01 per diluted share, and there was no impact to income from discontinued operations, net of tax. • For the quarter ended March 31, 2017, net income from continuing operations increased $3 million , or $0.01 per diluted share, and there was no impact to income from discontinued operations, net of tax. • For the quarter ended June 30, 2017, net income from continuing operations decreased $7 million , or $0.03 per diluted share, and income from discontinued operations, net of tax, increased by $2 million , or $0.01 per diluted share; and for the six months ended June 30, 2017, net income from continuing operations decreased $4 million , or $0.02 per diluted share, and income from discontinued operations, net of tax, increased by $2 million , or $0.01 per diluted share. • For the quarter ended September 30, 2017, net income from continuing operations increased $1 million , or zero cents per diluted share, and there was no impact to income from discontinued operations, net of tax; and for the nine months ended September 30, 2017, net income from continuing operations decreased $3 million , or $0.01 per diluted share, and income from discontinued operations, net of tax, increased by $2 million , or $0.01 per diluted share. • For the quarter ended December 31, 2017, net income from continuing operations increased $1 million or zero cents per diluted share, and income from discontinued operations, net of tax, increased by $3 million , or $0.01 per diluted share. The categories of misstatements and their impact on previously reported consolidated financial statements for the 2017 and 2016 quarterly periods are described below: (a) Customer Rebates The Company did not properly recognize expense associated with certain customer rebates, resulting in a misstatement of Net sales in the first and second quarters of 2017. The misstatements overstated previously reported Income before income taxes by $0.4 million and $1.4 million for the quarters ended March 31, 2017 and June 30, 2017, respectively. (b) Classification of Continuing Operations and Discontinued Operations Certain items of income related to PPG’s former Glass segment were inappropriately recorded in continuing operations rather than in discontinued operations. The misstatements overstated previously reported Income before income taxes by $2.5 million and $4.7 million for the quarters ended June 30, 2017 and December 31, 2017, respectively. The misstatements understated previously recorded Income from discontinued operations, net of tax, by $1.5 million and $2.9 million for the quarters ended June 30, 2017 and December 31, 2017, respectively. (c) Stock-Based Compensation In the fourth quarter of 2016, the Company improperly reduced the payout assumption for the 2015 grant of performance-based restricted stock units from 150% to 100% , which had the effect of reducing stock-based compensation expense in that period by $6.8 million . In the first quarter of 2017, the Company increased the payout assumption for these same restricted stock units from 100% back to 150% . These improper changes to the payout assumption for these restricted stock units resulted in a misstatement of stock-based compensation expense in both the fourth quarter of 2016 and the first quarter of 2017. (See Note 18, “Stock-Based Compensation (As Restated),” for further information concerning the Company’s accounting for Restricted Stock Units.) The misstatements overstated previously reported Income before income taxes by $6.8 million for the quarter ended December 31, 2016 and understated previously reported Income before income taxes by $6.8 million for the quarter ended March 31, 2017. (d) Classification of Business Restructuring Expense The Company misclassified the release of the unused portion of the reserve related to the 2015 business restructuring program in the fourth quarter of 2016 of $3.4 million . The income associated with the release of the reserve was classified as Other income rather than as a reduction to Business restructuring in the Consolidated Statement of Income. The misclassification had no impact on Income before taxes. (e) Employee Vacation Pay The Company did not properly recognize expense associated with a change in the Company’s vacation policy in the second and third quarters of 2017. Rather, the entire amount of expense associated with this change was recognized in the fourth quarter of 2017, resulting in a misstatement of expense in the second, third and fourth quarters of 2017. The misstatements overstated previously reported Income before income taxes by $0.9 million and $1.3 million for the quarters ended June 30, 2017 and September 30, 2017, respectively, and understated previously reported Income before taxes by $2.2 million for the quarter ended December, 31, 2017. The misstatements had no impact on Income before taxes for the year ended December 31, 2017. (f) Compensation Expense The Company did not properly record compensation expense related to a payment made to an employee upon his separation from the Company in the second quarter of 2017. Rather, the expense associated with this payment was recognized in the second, third and fourth quarters of 2017 resulting in a misstatement of expense in each of these periods. The misstatements overstated previously reported Income before income taxes by $3.5 million for the quarter ended June 30, 2017 and understated previously reported Income before taxes by $1.4 million and $2.1 million , respectively, for the quarters ended September 30, 2017 and December 31, 2017. The misstatements had no impact on Income before taxes for the year ended December 31, 2017. (g) Health Care Claims The Company did not properly recognize expense associated with the Company’s liability for employee health care claims in the second quarter of 2017. Rather, this expense was recognized in the third quarter of 2017, resulting in a misstatement of expense in the second and third quarters of 2017. The misstatements overstated previously reported Income before income taxes by $3.5 million for the quarter ended June 30, 2017 and understated previously reported Income before taxes by $3.5 million for the quarter ended September 30, 2017. The misstatements had no impact on Income before taxes for the year ended December 31, 2017. (h) Environmental Reserve In the first quarter of 2017, the Company failed to appropriately update the discount rate used to calculate a long-term environmental remediation reserve, which had the effect of understating Other expense by $0.5 million in the quarter. The misstatement overstated previously reported Income before taxes by $0.5 million for the quarter ended March 31, 2017. (i) Pension Expense The Company did not properly recognize pension expense in the third and fourth quarters of 2017. The misstatements overstated previously reported Income before income taxes by $1.0 million for the quarter ended September 30, 2017 and understated previously reported Income before taxes by $1.0 million for the quarter ended December 31, 2017. The misstatements had no impact on Income before taxes for the year ended December 31, 2017. (j) Income Taxes Adjustments related to the income tax effects of other restatement adjustments noted above. Quarterly Basis of Presentation (unaudited) (As Restated) We have prepared the accompanying unaudited financial statements included in Note 19 in accordance with the requirements of the Securities and Exchange Commission and accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Under these rules, certain footnotes and other financial information that are normally required for annual financial statements can be condensed or omitted. These statements include all adjustments, consisting only of normal, recurring adjustments, necessary for a fair presentation of the financial position of PPG Industries, Inc. and its subsidiaries (the "Company" or "PPG") and the results of their operations and their cash flows. All intercompany balances and transactions have been eliminated.These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in this Form 10-K/A for the year ended December 31, 2017. Quarterly Financial Information (unaudited) (As Restated) 2017 Quarter Ended Full Year 2017 (1) ($ in millions, except per share amounts) March 31 June 30 September 30 December 31 Net sales $3,486 $3,804 $3,776 $3,682 $14,748 Cost of sales (2) 1,905 2,082 2,101 2,119 8,207 Net income (loss) attributable to PPG Continuing operations $331 $497 $393 $148 $1,369 Discontinued operations 6 (1 ) 217 3 225 Net income $337 $496 $610 $151 $1,594 Earnings per common share Continuing operations $1.29 $1.93 $1.53 $0.59 $5.34 Discontinued operations 0.02 — 0.85 0.01 0.88 Earnings per common share $1.31 $1.93 $2.38 $0.60 $6.22 Earnings per common share - assuming dilution Continuing operations $1.28 $1.92 $1.52 $0.58 $5.31 Discontinued operations 0.02 — 0.84 0.01 0.87 Earnings per common share – assuming dilution $1.30 $1.92 $2.36 $0.59 $6.18 2016 Quarter Ended Full Year 2016 (1) ($ in millions except per share amounts) March 31 June 30 September 30 December 31 Net sales $3,411 $3,782 $3,660 $3,417 $14,270 Cost of sales (2) 1,817 1,988 1,978 1,910 7,693 Net income (loss) attributable to PPG Continuing operations $328 $339 ($211 ) $87 $543 Discontinued operations 19 31 27 253 330 Net income (loss) $347 $370 ($184 ) $340 $873 Earnings (loss) per common share Continuing operations $1.23 $1.26 ($0.79 ) $0.34 $2.05 Discontinued operations 0.07 0.12 0.10 0.96 1.24 Earnings (loss) per common share $1.30 $1.38 ($0.69 ) $1.30 $3.29 Earnings (loss) per common share - assuming dilution Continuing operations $1.22 $1.25 ($0.79 ) $0.33 $2.04 Discontinued operations 0.07 0.12 0.10 0.96 1.23 Earnings (loss) per common share – assuming dilution $1.29 $1.37 ($0.69 ) $1.29 $3.27 (1) Full year earnings-per-share was calculated using the full year weighted average shares outstanding. As such, the sum of the quarters may not equal the total earnings-per-share for the year. (2) Exclusive of depreciation and amortization. Quarterly Condensed Consolidated Statement of Income (unaudited) (As Restated) 2017 March 31 June 30 September 30 December 31 As Restated As Restated As Restated As Restated Net sales $3,486 $3,804 $3,776 $3,682 Cost of sales, exclusive of depreciation and amortization 1,905 2,082 2,101 2,119 Selling, general and administrative 882 872 902 908 Depreciation 79 81 85 86 Amortization 31 32 32 34 Research and development, net 110 113 114 116 Interest expense 25 26 27 27 Interest income (4 ) (4 ) (5 ) (7 ) Pension settlement charge 22 — — 38 Other charges 14 12 13 25 Other income (24 ) (69 ) (16 ) (41 ) Income from continuing operations before income taxes $446 $659 $523 $377 Income tax expense 110 157 124 224 Income from continuing operations $336 $502 $399 $153 Income from discontinued operations, net of tax 6 (1 ) 217 3 Net income attributable to the controlling and noncontrolling interests $342 $501 $616 $156 Less: Net income attributable to noncontrolling interests (5 ) (5 ) (6 ) (5 ) Net income (attributable to PPG) $337 $496 $610 $151 Amounts attributable to PPG: Income from continuing operations, net of tax $331 $497 $393 $148 Income (loss) from discontinued operations, net of tax 6 (1 ) 217 3 Net income (attributable to PPG) $337 $496 $610 $151 Earnings per common share: Income from continuing operations, net of tax $1.29 $1.93 $1.53 $0.59 Income (loss) from discontinued operations, net of tax 0.02 — 0.85 0.01 Net income (attributable to PPG) $1.31 $1.93 $2.38 $0.60 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.28 $1.92 $1.52 $0.58 Income (loss) from discontinued operations, net of tax 0.02 — 0.84 0.01 Net income (attributable to PPG) $1.30 $1.92 $2.36 $0.59 Dividends per common share $0.40 $0.40 $0.45 $0.45 Condensed Consolidated Statement of Income (unaudited) (As Restated) Six Months Ended June 30, 2017 Nine Months Ended September 30, 2017 As Restated As Restated Net sales $7,290 $11,066 Cost of sales, exclusive of depreciation and amortization 3,987 6,088 Selling, general and administrative 1,754 2,656 Depreciation 160 245 Amortization 63 95 Research and development, net 223 337 Interest expense 51 78 Interest income (8 ) (13 ) Pension settlement charge 22 22 Other charges 26 39 Other income (93 ) (109 ) Income from continuing operations before income taxes 1,105 1,628 Income tax expense 267 391 Income from continuing operations 838 1,237 Income from discontinued operations, net of tax 5 222 Net income attributable to the controlling and noncontrolling interests 843 1,459 Less: Net income attributable to noncontrolling interests 10 16 Net income (attributable to PPG) $833 $1,443 Amounts attributable to PPG: Income from continuing operations, net of tax $828 $1,221 Income from discontinued operations, net of tax 5 222 Net income (attributable to PPG) $833 $1,443 Earnings per common share: Income from continuing operations, net of tax $3.22 $4.75 Income from discontinued operations, net of tax 0.02 0.86 Net income (attributable to PPG) $3.24 $5.61 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $3.19 $4.72 Income from discontinued operations, net of tax 0.02 0.86 Net income (attributable to PPG) $3.21 $5.58 Dividends per common share $0.80 $1.25 Quarterly Condensed Consolidated Statement of Income (Unaudited) 2016 March 31 June 30 September 30 December 31 As Restated Net sales $3,411 $3,782 $3,660 $3,417 Cost of sales, exclusive of depreciation and amortization 1,817 1,988 1,978 1,910 Selling, general and administrative 897 930 893 868 Depreciation 79 79 82 79 Amortization 30 30 31 30 Research and development, net 114 115 115 115 Interest expense 31 31 34 29 Interest income (7 ) (7 ) (6 ) (6 ) Pension settlement charge — — 968 — Business restructuring — — — 191 Asbestos settlement, net 3 2 — — Other charges 17 29 12 117 Other income (14 ) (45 ) (21 ) (47 ) Income (loss) from continuing operations before income taxes $444 $630 ($426 ) $131 Income tax expense (benefit) 109 285 (220 ) 40 Income (loss) from continuing operations $335 $345 ($206 ) $91 Income from discontinued operations, net of tax 19 31 27 253 Net income (loss) attributable to the controlling and noncontrolling interests $354 $376 ($179 ) $344 Less: Net income attributable to noncontrolling interests (7 ) (6 ) (5 ) (4 ) Net income (loss) (attributable to PPG) $347 $370 ($184 ) $340 Amounts attributable to PPG: Income (loss) from continuing operations, net of tax $328 $339 ($211 ) $87 Income from discontinued operations, net of tax 19 31 27 253 Net income (loss) (attributable to PPG) $347 $370 ($184 ) $340 Earnings per common share: Income (loss) from continuing operations, net of tax $1.23 $1.26 ($0.79 ) $0.34 Income from discontinued operations, net of tax 0.07 0.12 0.10 0.96 Net income (loss) (attributable to PPG) $1.30 $1.38 ($0.69 ) $1.30 Earnings per common share – assuming dilution: Income (loss) from continuing operations, net of tax $1.22 $1.25 ($0.79 ) $0.33 Income from discontinued operations, net of tax 0.07 0.12 0.10 0.96 Net income (loss) (attributable to PPG) $1.29 $1.37 ($0.69 ) $1.29 Dividends per common share $0.36 $0.40 $0.40 $0.40 Quarterly Condensed Consolidated Statement of Comprehensive Income (unaudited) (As Restated) 2017 Quarter Ended ($ in millions) March 31 June 30 September 30 Net income attributable to the controlling and noncontrolling interests $342 $501 $616 Defined benefit pension and other postretirement benefit adjustments 21 (55 ) (29 ) Unrealized foreign currency translation gains/(losses) 279 82 26 Unrealized (losses)/gains – derivative financial instruments (13 ) (4 ) 1 Other comprehensive income/(loss), net of tax 287 23 (2 ) Total comprehensive income $629 $524 $614 Less: amounts attributable to noncontrolling interests: Net income (5 ) (5 ) (6 ) Unrealized foreign currency translation losses (7 ) (6 ) (2 ) Comprehensive income attributable to PPG $617 $513 $606 ($ in millions) Six Months Ended June 30, 2017 Nine Months Ended September 30, 2017 Net income attributable to the controlling and noncontrolling interests $843 $1,459 Defined benefit pension and other postretirement benefit adjustments (34 ) (63 ) Unrealized foreign currency translation losses 361 387 Unrealized losses – derivative financial instruments (17 ) (16 ) Other comprehensive income, net of tax 310 308 Total comprehensive income $1,153 $1,767 Less: amounts attributable to noncontrolling interests: Net income (10 ) (16 ) Unrealized foreign currency translation losses (13 ) (15 ) Comprehensive income attributable to PPG $1,130 $1,736 Quarterly Condensed Consolidated Balance Sheets (unaudited) (As Restated) 2017 ($ in millions) March 31 June 30 September 30 December 31 Assets Current assets Cash and cash equivalents $1,349 $1,569 $2,287 $1,436 Short-term investments 40 48 41 55 Receivables 3,013 3,191 3,155 2,903 Inventories 1,699 1,766 1,805 1,730 Assets held for sale 223 177 — — Other 439 390 350 353 Total current assets $6,763 $7,141 $7,638 $6,477 Property, plant and equipment, net 2,659 2,710 2,730 2,824 Goodwill 3,720 3,845 3,881 3,942 Identifiable intangible assets, net 2,080 2,118 2,099 2,045 Deferred income taxes 170 321 422 305 Investments 175 256 261 268 Other assets 587 582 585 677 Total $16,154 $16,973 $17,616 $16,538 Liabilities and Shareholders’ Equity Current liabilities Accounts payable and accrued liabilities $3,517 $3,656 $3,900 $3,781 Restructuring reserves 95 115 107 102 Short-term debt and current portion of long-term debt 604 619 616 12 Liabilities held for sale 69 54 — — Total current liabilities $4,285 $4,444 $4,623 $3,895 Long-term debt 3,817 3,998 4,089 4,134 Accrued pensions 712 748 759 729 Other postretirement benefits 720 755 767 699 Deferred income taxes 400 390 445 442 Other liabilities 934 910 928 967 Total liabilities $10,868 $11,245 $11,611 $10,866 Commitments and contingent liabilities Shareholders’ equity Common stock $969 $969 $969 $969 Additional paid-in capital 711 723 745 756 Retained earnings 16,214 16,606 17,101 17,140 Treasury stock, at cost (10,626 ) (10,616 ) (10,855 ) (11,251 ) Accumulated other comprehensive loss (2,076 ) (2,059 ) (2,063 ) (2,057 ) Total PPG shareholders’ equity $5,192 $5,623 $5,897 $5,557 Noncontrolling interests 94 105 108 115 Total shareholders’ equity $5,286 $5,728 $6,005 $5,672 Total $16,154 $16,973 $17,616 $16,538 Quarterly Condensed Consolidated Statement of Cash Flows (unaudited) (As Restated) 2017 Year to Date ($ in millions) March 31 June 30 September 30 December 31 Operating activities Net income attributable to the controlling and noncontrolling interests $342 $843 $1,459 $1,615 Less: Income from discontinued operations 6 5 222 225 Income from continuing operations $336 $838 $1,237 $1,390 Adjustments to reconcile to cash from operations: Depreciation and amortization 110 223 340 460 Defined benefit pension expense 18 34 52 65 Pension settlement charge 22 22 22 60 Stock-based compensation expense 9 17 26 35 Net gain, from sale of businesses — (25 ) (25 ) (25 ) Equity affiliate (income)/loss, net of dividends (1 ) 3 — (4 ) Deferred income taxes 6 (40 ) (53 ) 38 Contributions to pension plans (34 ) (37 ) (43 ) (87 ) Restructuring payments (10 ) (20 ) (31 ) (49 ) Change in certain asset and liability accounts (net of acquisitions): Receivables (296 ) (406 ) (350 ) (76 ) Inventories (157 ) (185 ) (200 ) (116 ) Other current assets (47 ) (49 ) (40 ) (43 ) Accounts payable and accrued liabilities 62 147 229 188 Noncurrent assets and liabilities, net 39 (14 ) (102 ) (170 ) Taxes and interest payable (82 ) (128 ) (115 ) (129 ) Other 24 52 71 14 Cash (used for)/from operating activities - continuing operations ($1 ) $432 $1,018 1,551 Cash from operating activities - discontinued operations 10 14 14 17 Cash from operating activities $9 $446 $1,032 $1,568 Investing activities Capital expenditures ($63 ) ($135 ) ($207 ) ($360 ) Business acquisitions, net of cash balances acquired (61 ) (62 ) (69 ) (225 ) Payments for acquisition of equity investment — (100 ) (100 ) (100 ) Net proceeds from the sale of businesses — 52 593 593 Purchase of short-term investments — — — (1 ) Payments for the settlement of cross currency swap contracts (34 ) (34 ) (34 ) (34 ) Proceeds from the settlement of cross currency swap contracts 19 19 37 37 Other 2 2 — 27 Cash (used for)/from investing activities - continuing operations ($137 ) ($258 ) $220 ($63 ) Cash used for investing activities - discontinued operations (1 ) (3 ) (4 ) (4 ) Cash (used for)/from investing activities ($138 ) ($261 ) $216 ($67 ) Financing activities Net change in borrowings with maturities of three months or less ($7 ) ($3 ) ($6 ) ($7 ) Net payments on commercial paper and short-term debt (32 ) (61 ) (81 ) (93 ) Repayment of long-term debt (7 ) (8 ) (9 ) (588 ) Payments related to tax withholding on stock-based compensation awards (16 ) (20 ) (25 ) (28 ) Purchase of treasury stock (163 ) (163 ) (413 ) (813 ) Issuance of treasury stock 9 20 45 52 Dividends paid on PPG common stock (103 ) (205 ) (321 ) (434 ) Other (53 ) (50 ) (41 ) (43 ) Cash used for financing activities ($372 ) ($490 ) ($851 ) ($1,954 ) Effect of currency exchange rate changes on cash and cash equivalents 30 54 70 69 Net (decrease) increase in cash and cash equivalents ($471 ) ($251 ) $467 ($384 ) Cash and cash equivalents, beginning of year $1,820 $1,820 $1,820 $1,820 Cash and cash equivalents, end of period $1,349 $1,569 $2,287 $1,436 Supplemental disclosures of cash flow information: Interest paid, net of amount capitalized $23 $52 $60 $100 Taxes paid, net of refunds $90 $326 $481 $648 Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $3,486 $— (a) $3,486 Selling, general and administrative 888 (6 ) (c) 882 Other charges 14 — (h) 14 Income from continuing operations before income taxes $440 $6 $446 Income tax expense 107 3 (j) 110 Income from continuing operations $333 $3 $336 Income from discontinued operations, net of tax 6 — 6 Net income attributable to the controlling and noncontrolling interests $339 $3 $342 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $334 $3 $337 Amounts attributable to PPG: Income from continuing operations, net of tax $328 $3 $331 Income from discontinued operations, net of tax 6 — 6 Net income (attributable to PPG) $334 $3 $337 Earnings per common share: Income from continuing operations, net of tax $1.28 $0.01 $1.29 Income from discontinued operations, net of tax 0.02 — 0.02 Net income (attributable to PPG) $1.30 $0.01 $1.31 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.27 $0.01 $1.28 Income from discontinued operations, net of tax 0.02 — 0.02 Net income (attributable to PPG) $1.29 $0.01 $1.30 Dividends per common share $0.40 $— $0.40 Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $3,806 ($2 ) (a) $3,804 Selling, general and administrative 865 7 (e),(f),(g) 872 Other income (72 ) 3 (b) (69 ) Income from continuing operations before income taxes $671 ($12 ) $659 Income tax expense 162 (5 ) (j) 157 Income from continuing operations $509 ($7 ) $502 Loss from discontinued operations, net of tax (3 ) 2 (b) (1 ) Net income attributable to the controlling and noncontrolling interests $506 ($5 ) $501 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $501 ($5 ) $496 Amounts attributable to PPG: Income from continuing operations, net of tax $504 ($7 ) $497 Loss from discontinued operations, net of tax (3 ) 2 (1 ) Net income (attributable to PPG) $501 ($5 ) $496 Earnings per common share: Income from continuing operations, net of tax $1.96 ($0.03 ) $1.93 Loss from discontinued operations, net of tax (0.01 ) 0.01 — Net income (attributable to PPG) $1.95 ($0.02 ) $1.93 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.95 ($0.03 ) $1.92 Loss from discontinued operations, net of tax (0.01 ) 0.01 — Net income (attributable to PPG) $1.94 ($0.02 ) $1.92 Dividends per common share $0.40 $— $0.40 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Six Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $7,292 ($2 ) (a) $7,290 Selling, general and administrative 1,753 1 (c),(e),(f),(g) 1,754 Other charges 26 — (h) 26 Other income (96 ) 3 (b) (93 ) Income from continuing operations before income taxes 1,111 $ (6 ) 1,105 Income tax expense 269 (2 ) (j) 267 Income from continuing operations 842 $ (4 ) 838 Income from discontinued operations, net of tax 3 2 (b) 5 Net income attributable to the controlling and noncontrolling interests $845 ($2 ) $843 Less: Net income attributable to noncontrolling interests (10 ) — (10 ) Net income (attributable to PPG) $835 ($2 ) $833 Amounts attributable to PPG: Income from continuing operations, net of tax $832 ($4 ) $828 Income from discontinued operations, net of tax 3 2 5 Net income (attributable to PPG) $835 ($2 ) $833 Earnings per common share: Income from continuing operations, net of tax $3.23 ($0.01 ) $3.22 Income from discontinued operations, net of tax 0.01 0.01 0.02 Net income (attributable to PPG) $3.24 $— $3.24 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $3.21 ($0.02 ) $3.19 Income from discontinued operations, net of tax 0.01 0.01 0.02 Net income (attributable to PPG) $3.22 ($0.01 ) $3.21 Dividends per common share $0.80 $— $0.80 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Cost of sales, exclusive of depreciation and amortization 2,100 1 (i) 2,101 Selling, general and administrative 905 (3 ) (e),(f),(g) 902 Income from continuing operations before income taxes $521 $2 $523 Income tax expense 123 1 (j) 124 Income from continuing operations $398 $1 $399 Income from discontinued operations, net of tax 217 — 217 Net income attributable to the controlling and noncontrolling interests $615 $1 $616 Less: Net income attributable to noncontrolling interests (6 ) — (6 ) Net income (attributable to PPG) $609 $1 $610 Amounts attributable to PPG: Income from continuing operations, net of tax $392 $1 $393 Income from discontinued operations, net of tax 217 — 217 Net income (attributable to PPG) $609 $1 $610 Earnings per common share: Income from continuing operations, net of tax $1.53 $— $1.53 Income from discontinued operations, net of tax 0.85 — 0.85 Net income (attributable to PPG) $2.38 $— $2.38 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.52 $— $1.52 Income from discontinued operations, net of tax 0.84 — 0.84 Net income (attributable to PPG) $2.36 $— $2.36 Dividends per common share $0.45 $— $0.45 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Nine Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $11,068 ($2 ) (a) $11,066 Cost of sales, exclusive of depreciation and amortization 6,087 1 (i) 6,088 Selling, general and administrative 2,658 (2 ) (c),(e),(f) 2,656 Other charges 39 — (h) 39 Other income (112 ) 3 (b) (109 ) Income from continuing operations before income taxes $1,632 ($4 ) $1,628 Income tax expense 392 (1 ) (j) 391 Income from continuing operations $1,240 ($3 ) $1,237 Income from discontinued operations, net of tax 220 2 (b) 222 Net income attributable to the controlling and noncontrolling interests $1,460 ($1 ) $1,459 Less: Net income attributable to noncontrolling interests (16 ) — (16 ) Net income (attributable to PPG) $1,444 ($1 ) $1,443 Amounts attributable to PPG: Income from continuing operations, net of tax $1,224 ($3 ) $1,221 Income from discontinued operations, net of tax 220 2 222 Net income (attributable to PPG) $1,444 ($1 ) $1,443 Earnings per common share: Income from continuing operations, net of tax $4.76 ($0.01 ) $4.75 Income from discontinued operations, net of tax 0.86 — 0.86 Net income (attributable to PPG) $5.62 ($0.01 ) $5.61 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $4.73 ($0.01 ) $4.72 Income from discontinued operations, net of tax 0.85 0.01 0.86 Net income (attributable to PPG) $5.58 $— $5.58 Dividends per common share $1.25 $— $1.25 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Cost of sales, exclusive of depreciation and amortization $2,117 $2 (b),(i) $2,119 Selling, general and administrative 912 (4 ) (e),(f) 908 Other income (42 ) 1 (b) (41 ) Income from continuing operations before income taxes $376 $1 $377 Income tax expense 224 — (j) 224 Income from continuing operations $152 $1 $153 Income from discontinued operations, net of tax — 3 (b) 3 Net income attributable to the controlling and noncontrolling interests $152 $4 $156 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $147 $4 $151 Amounts attributable to PPG: Income from continuing operations, net of tax $147 $1 $148 Income from discontinued operations, net of tax — 3 3 Net income (attributable to PPG) $147 $4 $151 Earnings per common share: Income from continuing operations, net of tax $0.58 $0.01 $0.59 Income from discontinued operations, net of tax — 0.01 0.01 Net income (attributable to PPG) $0.58 $0.02 $0.60 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $0.58 $— $0.58 Income from discontinued operations, net of tax — 0.01 0.01 Net income (attributable to PPG) $0.58 $0.01 $0.59 Dividends per common share $0.45 $— $0.45 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Selling, general and administrative $861 $7 (c) $868 Business restructuring 195 (4 ) (d) 191 Other income (51 ) 4 (d) (47 ) Income from continuing operations before income taxes $138 ($7 ) $131 Income tax expense 43 (3 ) (j) 40 Income from continuing operations $95 ($4 ) $91 Income from discontinued operations, net of tax 253 — 253 Net income attributable to the controlling and noncontrolling interests $348 ($4 ) $344 Less: Net income attributable to noncontrolling interests (4 ) — (4 ) Net income (attributable to PPG) $344 ($4 ) $340 Amounts attributable to PPG: Income from continuing operations, net of tax $91 ($4 ) $87 Income from discontinued operations, net of tax 253 — 253 Net income (attributable to PPG) $344 ($4 ) $340 Earnings per common share: Income from continuing operations, net of tax $0.35 ($0.01 ) $0.34 Income f

Reportable Business Segment Inf

Reportable Business Segment Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Reportable Business Segment Information	Reportable Business Segment Information (As Restated) Segment Organization and Products PPG is a multinational manufacturer with 10 operating segments (which the Company refers to as “strategic business units”) that are organized based on the Company’s major products lines. These operating segments are also the Company’s reporting units for purposes of testing goodwill for impairment (see Note 1, “Summary of Significant Accounting Policies”). The Company’s reportable business segments include the following two segments: Performance Coatings and Industrial Coatings. The operating segments have been aggregated based on economic similarities, the nature of their products, production processes, end-use markets and methods of distribution. The Performance Coatings reportable segment is comprised of the refinish, aerospace, architectural coatings – Americas and Asia-Pacific, architectural coatings - EMEA, and protective and marine coatings operating segments. This reportable segment primarily supplies a variety of protective and decorative coatings, sealants and finishes along with paint strippers, stains and related chemicals, as well as transparencies and transparent armor. The Industrial Coatings reportable segment is comprised of the automotive original equipment manufacturer (“OEM”) coatings, industrial coatings, packaging coatings, coatings services and the specialty coatings and materials operating segments. This reportable segment primarily supplies a variety of protective and decorative coatings and finishes along with adhesives, sealants, metal pretreatment products, optical monomers and coatings, precipitated silicas and other specialty materials. Effective January 1, 2018, the coating services operating segment has been merged into the industrial coatings operating segment and the Company will have 9 operating segments. Management teams and operations will be realigned to better deliver our total value proposition and provide optimal solutions to our customers, as well as to achieve operational efficiencies. Production facilities and markets for Performance Coatings and Industrial Coatings are global. PPG’s reportable segments continue to pursue opportunities to further develop their global markets, including efforts in Asia, Eastern Europe and Latin America. Each of the reportable segments in which PPG is engaged is highly competitive. The diversification of our product lines and the worldwide markets served tend to minimize the impact on PPG’s total sales and income from continuing operations of changes in demand in a particular market or in a particular geographic area. The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies (See Note 1, “Summary of Significant Accounting Policies”). The Company allocates resources to operating segments and evaluates the performance of operating segments based upon segment income, which is income before interest expense – net, income taxes, and noncontrolling interests and excludes certain charges which are considered to be unusual or non-recurring. The Company also evaluates performance of operating segments based on working capital reduction, margin growth, and sales volume growth. Legacy items include current costs related to former operations of the Company, including certain environmental remediation, pension and other postretirement benefit costs, and certain charges for legal and other matters which are considered to be unusual or non-recurring. These legacy costs are excluded from the segment income that is used to evaluate the performance of the operating segments. Corporate unallocated costs include the costs of corporate staff functions not directly associated with the operating segments, the cost of corporate legal cases, net of related insurance recoveries and the cost of certain insurance and stock-based compensation programs. Net periodic pension expense is allocated to the operating segments and the portion of net periodic pension expense related to the corporate staff functions is included in the Corporate unallocated costs. Product movement between Performance Coatings and Industrial Coatings is limited, is accounted for as an inventory transfer, and is recorded at cost plus a mark-up, the impact of which is not significant to the segment income of the reportable segments. As Restated ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / (1) Consolidated Totals 2017 Net sales to external customers $8,730 $6,018 $ — $14,748 Intersegment net sales — — — — Total net sales $8,730 $6,018 $ — $14,748 Segment income $1,321 $972 $ — $2,293 Legacy items (2) (2 ) Pension settlement charge (60 ) Transaction-related costs (5) (9 ) Asset write-downs (7 ) Gain from sale of the Plaka business 25 Gain from a legal settlement 18 Gain from sale of a non-operating asset 13 Interest expense, net of interest income (85 ) Corporate unallocated (1) (181 ) Income before income taxes $2,005 Depreciation and amortization $272 $164 $24 $460 Share of net earnings (loss) of equity affiliates $2 $— $10 $12 Segment assets (3) $9,763 $4,563 $2,212 $16,538 Investment in equity affiliates $32 $13 $89 $134 Expenditures for property (including business acquisitions) $224 $328 $133 $685 As Restated ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / (1) Consolidated Totals 2016 Net sales to external customers $8,580 $5,690 $— $14,270 Intersegment net sales — 1 (1 ) — Total net sales $8,580 $5,691 ($1 ) $14,270 Segment income $1,314 $1,042 $— $2,356 Legacy items (2) (114 ) Business restructuring charge (191 ) Transaction-related costs (5) (8 ) Pension settlement charges (968 ) Asset write-downs (23 ) Gains on disposals of ownership interests in business affiliates 46 Interest expense, net of interest income (99 ) Corporate unallocated (1) (220 ) Income before income taxes $779 Depreciation and amortization $272 $143 $25 $440 Share of net earnings/(loss) of equity affiliates $5 $1 $2 $8 Segment assets (3) $9,168 $3,972 $2,631 $15,771 Investment in equity affiliates $30 $13 $3 $46 Expenditures for property (including business acquisitions) $187 $510 $32 $729 ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / Non-Segment Items (1) Consolidated Totals 2015 Net sales to external customers $8,765 $5,476 $— $14,241 Intersegment net sales — 1 (1 ) — Total net sales $8,765 $5,477 ($1 ) $14,241 Segment income $1,302 $985 $— $2,287 Legacy items (2) (51 ) Business restructuring charge (136 ) Transaction-related costs (5) (44 ) Interest expense, net of interest income (86 ) Corporate unallocated (1) (225 ) Income before income taxes $1,745 Depreciation and amortization $296 $124 $26 $446 Share of net earnings of equity affiliates $7 $— ($3 ) $4 Segment assets (3) $9,917 $3,643 $3,516 $17,076 Investment in equity affiliates $45 $13 $36 $94 Expenditures for property (including business acquisitions) $298 $414 $38 $750 ($ in millions) Geographic Information 2017 2016 2015 Net sales (4) As Restated United States and Canada $6,307 $6,254 $6,232 Europe, Middle East and Africa (“EMEA”) 4,389 4,164 4,103 Asia Pacific 2,523 2,431 2,433 Latin America 1,529 1,421 1,473 Total $14,748 $14,270 $14,241 Segment income United States and Canada $1,129 $1,152 $1,176 EMEA 569 590 539 Asia Pacific 361 382 359 Latin America 234 232 213 Total $2,293 $2,356 $2,287 Property—net United States and Canada $1,224 $1,184 $1,101 EMEA 826 726 805 Asia Pacific 493 447 431 Latin America 281 251 271 Total $2,824 $2,608 $2,608 (1) Corporate intersegment net sales represent intersegment net sales eliminations. Corporate unallocated costs include the costs of corporate staff functions not directly associated with the operating segments, certain legal and insurance costs and stock-based compensation expense. (2) Legacy items include current costs related to former operations of the Company, including certain environmental remediation, pension and other postretirement benefit costs, legal costs and certain charges which are considered to be non-recurring. Until April 2016, legacy items also include equity earnings from PPG’s minority investment in Pittsburgh Glass Works, LLC. The Legacy items for 2016 include an environmental remediation pre-tax charge of $82 million . These charges relate to continued environmental remediation activities at legacy chemicals sites, primarily at PPG’s former Jersey City, N.J. chromium manufacturing plant and associated sites (Refer to Note 14, “Commitments and Contingent Liabilities”). (3) Segment assets are the total assets used in the operation of each segment. Corporate assets are principally cash and cash equivalents, cash held in escrow, short term investments, deferred tax assets and, until April 2016, PPG’s equity investment in it’s former automotive glass and services business. Non-segment items also includes the assets of businesses which have been reclassified as discontinued operations in the Consolidated Statement of Income. (Refer to Note 3, “Acquisitions and Divestitures”). (4) Net sales to external customers are attributed to geographic regions based upon the location of the operating unit shipping the product. (5) Transaction-related costs include advisory, legal, accounting, valuation, and other professional or consulting fees incurred to effect significant acquisitions, as well as similar fees and other costs to effect divestitures not classified as discontinued operations. These costs also include the flow-through cost of sales for the step up to fair value of inventory acquired in acquisitions.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	Schedule II – Valuation and Qualifying Accounts Allowance for Doubtful Accounts for the Years Ended December 31, 2017 , 2016 , and 2015 ($ in millions) Balance at Beginning of Year Charged to Costs and Expenses Deductions(1) Balance at End of Year 2017 $36 $15 ($26 ) $25 2016 $43 $22 ($29 ) $36 2015 $80 $10 ($47 ) $43 (1) Notes and accounts receivable written off as uncollectible, net of recoveries, amounts attributable to divestitures and changes attributable to foreign currency translation.

Summary of Significant Accoun28

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of PPG Industries, Inc. (“PPG” or the “Company”) and all subsidiaries, both U.S. and non-U.S., that it controls. PPG owns more than 50% of the voting stock of most of the subsidiaries that it controls. For those consolidated subsidiaries in which the Company’s ownership is less than 100% , the outside shareholders’ interests are shown as noncontrolling interests. Investments in companies in which PPG owns 20% to 50% of the voting stock and has the ability to exercise significant influence over operating and financial policies of the investee are accounted for using the equity method of accounting. As a result, PPG’s share of income or losses from such equity affiliates is included in the accompanying consolidated statement of income and PPG’s share of these companies’ shareholders’ equity is included in “Investments” in the accompanying consolidated balance sheet. Transactions between PPG and its subsidiaries are eliminated in consolidation.
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of income and expenses during the reporting period. Such estimates also include the fair value of assets acquired and liabilities assumed resulting from the allocation of the purchase price related to business combinations consummated. Actual outcomes could differ from those estimates.
Revenue Recognition	Revenue Recognition The Company recognizes revenue when the earnings process is complete. Revenue is recognized by all operating segments when goods are shipped and title to inventory and risk of loss passes to the customer or when services have been rendered.
Shipping and Handling Costs	Shipping and Handling Costs Amounts billed to customers for shipping and handling are reported in “Net sales” in the accompanying consolidated statement of income. Shipping and handling costs incurred by the Company for the delivery of goods to customers are included in “Cost of sales, exclusive of depreciation and amortization” in the accompanying consolidated statement of income.
Selling, General and Administrative Costs	Selling, General and Administrative Costs Amounts presented as “Selling, general and administrative” in the accompanying consolidated statement of income are comprised of selling, customer service, distribution and advertising costs, as well as the costs of providing corporate-wide functional support in such areas as finance, law, human resources and planning. Distribution costs pertain to the movement and storage of finished goods inventory at company-owned and leased warehouses and other distribution facilities.
Advertising Costs, Policy	Advertising Costs Advertising costs are expensed as incurred
Research and Development Expense, Policy	Research and Development Research and development costs, which consist primarily of employee related costs, are charged to expense as incurred.
Legal Costs	Legal Costs Legal costs, primarily include costs associated with acquisition and divestiture transactions, general litigation, environmental regulation compliance, patent and trademark protection and other general corporate purposes, are charged to expense as incurred.
Foreign Currency Translation	Foreign Currency Translation The functional currency of most significant non-U.S. operations is their local currency. Assets and liabilities of those operations are translated into U.S. dollars using year-end exchange rates; income and expenses are translated using the average exchange rates for the reporting period. Unrealized foreign currency translation gains and losses are deferred in accumulated other comprehensive loss, a separate component of shareholders’ equity.
Cash Equivalents	Cash Equivalents Cash equivalents are highly liquid investments (valued at cost, which approximates fair value) acquired with an original maturity of three months or less.
Short-term Investments	Short-term Investments Short-term investments are highly liquid, high credit quality investments (valued at cost plus accrued interest) that have stated maturities of greater than three months to one year. The purchases and sales of these investments are classified as investing activities in the consolidated statement of cash flows.
Marketable Equity Securities	Marketable Equity Securities The Company’s investment in marketable equity securities is recorded at fair market value and reported in “Other current assets” and “Investments” in the accompanying consolidated balance sheet with changes in fair market value recorded in income for those securities designated as trading securities and in other comprehensive income, net of tax, for those securities designated as available for sale.
Inventories	Inventories Inventories are stated at the lower of cost or net realizable value. Most U.S. inventories are stated at cost, using the last-in, first-out (“LIFO”) method of accounting, which does not exceed net realizable value. All other inventories are stated at cost, using the first-in, first-out (“FIFO”) method of accounting, which does not exceed net realizable value. PPG determines cost using either average or standard factory costs, which approximate actual costs, excluding certain fixed costs such as depreciation and property taxes. See Note 4, “Working Capital Detail” for further information concerning the Company’s inventory.
Derivatives, Policy	Derivative Financial Instruments The Company recognizes all derivative financial instruments (a “derivative”) as either assets or liabilities at fair value on the consolidated balance sheet. The accounting for changes in the fair value of a derivative depends on the use of the instrument. For a derivative that is considered “effective” as a hedge of an exposure to variability in expected future cash flows (cash flow hedge), the effective portion of the gain or loss on the derivative is recorded in other comprehensive income (“OCI”) and the ineffective portion, if any, is reported in income from continuing operations. Amounts accumulated in OCI are reclassified into income from continuing operations in the same period or periods during which the hedged transactions are recorded in income from continuing operations. For a derivative that is considered “effective” as a hedge of an exposure to changes in the fair value (fair value hedge) of an asset, a liability or a firm commitment, the change in the derivative’s fair value is reported in income from continuing operations, offsetting the gain or loss recognized for the change in fair value of the asset, liability, or firm commitment that is being hedged. For a derivative, debt or other financial instrument that is considered “effective” as a hedge of a net investment in a foreign operation, the gain or loss associated with the financial instrument is reported as a translation gain or loss in accumulated other comprehensive income (“AOCI”). Gains and losses in AOCI related to hedges of the Company’s net investments in foreign operations are reclassified out of AOCI and recognized in income from continuing operations upon a substantial liquidation, sale or partial sale of such investments or upon impairment of all or a portion of such investments. The cash flow impact of these instruments have been and will be classified as investing activities in the consolidated statement of cash flows. Changes in the fair value of derivative instruments not designated as hedges for hedge accounting purposes are recognized in income from continuing operations in the period of change.
Property	Property, Plant and Equipment Property, plant and equipment is recorded at cost. Depreciation is computed on a straight-line method based on the estimated useful lives of related assets. Additional depreciation expense is recorded when facilities or equipment are subject to abnormal economic conditions or obsolescence. The cost of significant improvements that add to productive capacity or extend the lives of properties are capitalized. Costs for repairs and maintenance are charged to expense as incurred. When a capitalized asset is retired or otherwise disposed of, the original cost and related accumulated depreciation balance are removed from the accounts and any related gain or loss is recorded in income from continuing operations. The amortization cost of capitalized leased assets is recorded in depreciation expense. Property and other long-lived assets are reviewed for impairment whenever events or circumstances indicate that their carrying amounts may not be recoverable. See Note 5, “Property, Plant and Equipment” for further details.
Goodwill and Identifiable Intangible Assets	Goodwill and Identifiable Intangible Assets Goodwill represents the excess of the cost over the fair value of acquired identifiable tangible and intangible assets less liabilities assumed from acquired businesses. Identifiable intangible assets acquired in business combinations are recorded based upon their fair value at the date of acquisition. The Company tests goodwill of each reporting unit for impairment at least annually in connection with PPG’s strategic planning process. The Company tests goodwill for impairment by either performing a qualitative evaluation or a quantitative test. The qualitative evaluation is an assessment of factors, including reporting unit specific operating results as well as industry, market and general economic conditions, to determine whether it is more likely than not that the fair values of a reporting unit is less than its carrying amount, including goodwill. The Company may elect to bypass this qualitative assessment for some or all of its reporting units and perform a quantitative test. The quantitative goodwill impairment test is performed during the fourth quarter by comparing the estimated fair value of the associated reporting unit as of September 30 to its carrying value. The Company’s reporting units are its operating segments. (See Note 20, “Reportable Business Segment Information,” for further information concerning the Company’s operating segments.) Fair value is estimated using discounted cash flow methodologies. The Company has determined that certain acquired trademarks have indefinite useful lives. The Company tests the carrying value of these trademarks for impairment at least annually, or as needed whenever events and circumstances indicate that their carrying amount may not be recoverable. The annual assessment takes place in the fourth quarter of each year either by completing a qualitative assessment or quantitatively by comparing the estimated fair value of each trademark as of September 30 to its carrying value. Fair value is estimated by using the relief from royalty method (a discounted cash flow methodology). The qualitative assessment includes consideration of factors, including revenue relative to the asset being assessed, the operating results of the related business as well as industry, market and general economic conditions, to determine whether it is more likely than not that the fair value of the asset is less than its carrying amount. Identifiable intangible assets with finite lives are amortized on a straight-line basis over their estimated useful lives ( 1 to 30 years) and are reviewed for impairment whenever events or circumstances indicate that their carrying amount may not be recoverable.
Allowance for Doubtful Accounts	Receivables and Allowances All trade receivables are reported on the balance sheet at the outstanding principal adjusted for any allowance for credit losses and any charge offs. The Company provides an allowance for doubtful accounts to reduce receivables to their estimated net realizable value when it is probable that a loss will be incurred. Those estimates are based on historical collection experience, current economic and market conditions, a review of the aging of accounts receivable and the assessments of current creditworthiness of customers.
Product Warranties	Product Warranties The Company accrues for product warranties at the time the associated products are sold based on historical claims experience. The reserve, pre-tax charges against income and cash outlays for product warranties were not significant to the consolidated financial statements of the Company for any year presented.
Asset Retirement Obligations	Asset Retirement Obligations An asset retirement obligation represents a legal obligation associated with the retirement of a tangible long-lived asset that is incurred upon the acquisition, construction, development or normal operation of that long-lived asset. PPG recognizes asset retirement obligations in the period in which they are incurred, if a reasonable estimate of fair value can be made. The asset retirement obligation is subsequently adjusted for changes in fair value. The associated estimated asset retirement costs are capitalized as part of the carrying amount of the long-lived asset and depreciated over its useful life. PPG’s asset retirement obligations are primarily associated with the retirement or closure of certain assets used in PPG’s manufacturing process. The accrued asset retirement obligation recorded on PPG’s balance sheet was $19 million and $18 million as of December 31, 2017 and 2016 , respectively. PPG’s only conditional asset retirement obligation relates to the possible future abatement of asbestos contained in certain PPG production facilities. The asbestos in PPG’s production facilities arises from the application of normal and customary building practices in the past when the facilities were constructed. This asbestos is encapsulated in place and, as a result, there is no current legal requirement to abate it. Inasmuch as there is no requirement to abate, the Company does not have any current plans or an intention to abate and therefore the timing, method and cost of future abatement, if any, are not known. The Company has not recorded an asset retirement obligation associated with asbestos abatement, given the uncertainty concerning the timing of future abatement, if any.
Accounting Standards Adopted in 2017	Accounting Standards Adopted in 2017 PPG’s adoption of the following accounting standard updates (“ASU”) in 2017 did not have a material impact on PPG's consolidated financial position, results of operations or cash flows: Accounting Standard Update 2017-04 Simplifying the Test for Goodwill Impairment 2016-18 Restricted Cash 2016-09 Improvements to Employee Share-Based Payment Accounting
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	Accounting Standards to be Adopted in Future Years In February 2018, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2018-2, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” This ASU allows a reclassification from Accumulated other comprehensive income to Retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. Early adoption of this ASU is permitted. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging - Targeted Improvements to Accounting for Hedging Activities." This ASU modifies the presentation and disclosure of hedging results. Further, it provides partial relief on the timing of certain aspects of hedge documentation and eliminates the requirement to recognize hedge ineffectiveness separately in income. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. Early adoption of this ASU is permitted. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In May 2017, the FASB issued ASU No. 2017-09, "Stock Compensation - Scope of Modification Accounting." This ASU requires all equity award modifications to be accounted for as a modification unless the fair value, vesting conditions and classification of the award as equity or liability are the same as the classification of the original award immediately before the original award is modified. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In March 2017, the FASB issued ASU No. 2017-07, "Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost." This ASU requires the service cost component of net benefit costs to be disaggregated from all other components and be reported in the same line item or items as other compensation costs. The other components of net benefit cost are required to be presented in the income statement separately from the service cost. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operation or cash flows. Beginning January 1, 2018, in connection with the adoption of this new ASU, PPG will change the method by which pension costs are allocated to its strategic business units. Namely, only service costs will be attributed to the strategic business units and all other components will remain in unallocated corporate overhead. PPG will recast its statement of operations and segment income for this change in allocation. In August 2016, the FASB issued ASU No. 2016-15, "Classification of Certain Cash Receipts and Cash Payments." This ASU addresses eight specific cash flow issues with the objective of eliminating the existing diversity in practice. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2017 and for interim periods therein. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses.” This ASU requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. The amendments in this ASU are effective for fiscal years beginning after December 15, 2019 and for interim periods therein. Entities may chose to adopt the new ASU as of its fiscal year beginning after December 15, 2018. PPG does not believe this ASU will have a material impact on its consolidated financial position, results of operations or cash flows. In February 2016, the FASB issued ASU No. 2016-02, “Leases.” This ASU requires all lessees to recognize on the balance sheet right to use assets and lease liabilities for the rights and obligations created by lease arrangements with terms greater than 12 months. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018 and for interim periods therein. PPG is in the process of assessing the impact the adoption of this ASU will have on its consolidated financial position, results of operations and cash flows. At a minimum, total assets and total liabilities will increase in the period the ASU is adopted. Early adoption of this ASU is permitted. At December 31, 2017, PPG’s undiscounted future minimum payments outstanding for lease obligations were approximately $840 million . In January 2016, the FASB issued ASU No. 2016-01, “Recognition and Measurement of Financial Assets and Liabilities.” This ASU simplifies the accounting and disclosures related to equity investments. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017 and for interim periods therein. Adoption of this ASU will not have a material impact on PPG’s consolidated financial position, results of operations or cash flows. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers: Topic 606.” This ASU replaces nearly all existing U.S. GAAP guidance on revenue recognition. The standard prescribes a five-step model for recognizing revenue, the application of which will require significant judgment. The amendments in this ASU are effective for fiscal years beginning after December 15, 2017, and for interim periods therein. The provisions of this ASU may be applied retroactively or on a modified retrospective (cumulative effect) basis. PPG will adopt the standard using the modified retrospective approach in January 2018. PPG believes the preponderance of the Company’s contracts with customers are standard ship and bill arrangements where revenue is recognized at the time of shipment. Under the provisions of this ASU, PPG believes certain costs currently reported in Selling, general and administrative costs will be reclassified to Cost of sales, exclusive of depreciation and amortization on the Consolidated Statement of Income, as they represent costs incurred in satisfaction of performance obligations. In addition, PPG expects the cost of certain customer incentives to be recorded as a reduction of Net sales rather than Cost of sales, exclusive of depreciation and amortization or Selling, general and administrative costs. Adoption of this ASU will not have a significant impact on PPG’s consolidated financial position, results of operations and cash flows.

Summary of Significant Accoun29

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Research and Development	($ in millions) 2017 2016 2015 Research and development – total $474 $479 $484 Less depreciation on research facilities 21 20 18 Research and development, net $453 $459 $466

Acquisitions and Dispositions (

Acquisitions and Dispositions (Tables)	12 Months Ended
	Dec. 31, 2017
MetoKote Corporation
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	($ in millions) Current assets $38 Property, plant, and equipment 73 Identifiable intangible assets with finite lives 86 Goodwill 166 Deferred income taxes (a) (12 ) Total assets $351 Current liabilities (23 ) Other long-term liabilities (22 ) Total liabilities ($45 ) Total purchase price, net of cash acquired $306
Glass Segment
Business Acquisition [Line Items]
Disposal Groups, Including Discontinued Operations	The net sales and income from discontinued operations related to the former Glass segment for the three years ended December 31, 2017 , 2016 , and 2015 were as follows: ($ in millions) 2017 2016 2015 As Restated Net sales $217 $908 $1,089 Income from operations $30 $111 $137 Net gains on the divestitures of businesses 343 421 — Income tax expense 140 202 42 Income from discontinued operations, net of tax $233 $330 $95 North American Fiber Glass Business On September 1, 2017, PPG completed the sale of its North American fiber glass business to Nippon Electric Glass Co. Ltd. (“NEG”). Cash proceeds from the sale were $541 million , resulting in a pre-tax gain of $343 million , net of certain accruals and contingencies established in conjunction with the divestiture. PPG’s fiber glass operations included manufacturing facilities in Chester, South Carolina, and Lexington and Shelby, North Carolina; and administrative and research-and-development operations in Shelby and in Harmar, Pennsylvania, near Pittsburgh. The business, which employed more than 1,000 people and had net sales of approximately $350 million in 2016, supplies the transportation, energy, infrastructure and consumer markets. The Company's December 31, 2016 consolidated balance sheet has been recast to present the assets and liabilities of the North American fiber glass business as held for sale. The major classes of assets and liabilities of the Glass segment included in the PPG consolidated balance sheet at December 31, 2016 were as follows: ($ in millions) December 31, 2016 Receivables. net $38 Inventory 32 Other current assets 1 Property, plant, and equipment, net 151 Deferred income taxes (a) (30 ) Other non-current assets 1 Assets held for sale $193 Accounts payable and accrued liabilities 52 Long-term liabilities 12 Liabilities held for sale $64 (a) The net deferred income tax liability is included in assets held for sale due to the Company's tax jurisdictional netting.

Working Capital Detail (Tables)

Working Capital Detail (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure Components Of Working Capital Detail [Abstract]
Components of Working Capital Detail	Working Capital Detail (As Restated) ($ in millions) 2017 2016 As Restated Receivables Trade - net (1) $2,559 $2,288 Equity affiliates 5 2 Other - net 339 364 Total $2,903 $2,654 Inventories (2) Finished products $1,083 $947 Work in process 177 165 Raw materials 437 370 Supplies 33 32 Total $1,730 $1,514 Accounts payable and accrued liabilities Trade $2,321 $1,907 Accrued payroll 441 443 Customer rebates 261 235 Other postretirement and pension benefits 78 124 Income taxes 100 94 Other 580 657 Total $3,781 $3,460 (1) Allowance for Doubtful Accounts was $25 million and $36 million as of December 31, 2017 and 2016 , respectively. (2) Inventories valued using the LIFO method of inventory valuation comprised 34% and 38% of total gross inventory values as of December 31, 2017 and 2016 , respectively. If the FIFO method of inventory valuation had been used, inventories would have been $103 million and $106 million higher as of December 31, 2017 and 2016 , respectively. During the years ended December 31, 2017 and 2016 , certain inventories accounted for on the LIFO method of accounting were reduced, which resulted in the liquidation of certain quantities carried at costs prevailing in prior years. The effect on income from continuing operations was zero and income of $2 million for the years ended December 31, 2017 and 2016 , respectively.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment ($ in millions) Useful Lives (years) 2017 2016 Land and land improvements 1-30 $487 $451 Buildings 20-40 1,488 1,324 Machinery and equipment 5-25 3,432 3,076 Other 3-20 958 774 Construction in progress 229 380 Total (1) $6,594 $6,005 Less: accumulated depreciation 3,770 3,397 Net $2,824 $2,608 (1) Interest capitalized in 2017 , 2016 and 2015 was $7 million , $8 million and $9 million , respectively.

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Investments	Investments ($ in millions) 2017 2016 Investments in equity affiliates $135 $46 Marketable equity securities - Trading (See Note 9) 79 78 Other 54 55 Total $268 $179

Goodwill and Other Identifiab34

Goodwill and Other Identifiable Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Carrying Amount of Goodwill Attributable to Each Reportable Segment	Goodwill ($ in millions) Performance Coatings Industrial Coatings Total January 1, 2016 $3,073 $552 $3,625 Acquisitions 6 168 174 Foreign currency translation (209 ) (18 ) (227 ) December 31, 2016 $2,870 $702 $3,572 Acquisitions 23 89 112 Foreign currency translation 211 47 258 December 31, 2017 $3,104 $838 $3,942
Identifiable Intangible Assets with Finite Lives	Identifiable Intangible Assets December 31, 2017 December 31, 2016 ($ in millions) Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Indefinite-Lived Identifiable Intangible Assets Trademarks $1,158 $— $1,158 $1,107 $— $1,107 Definite-Lived Identifiable Intangible Assets Acquired technology $613 ($489 ) $124 $587 ($446 ) $141 Customer-related 1,437 (762 ) 675 1,272 (618 ) 654 Tradenames 166 (87 ) 79 142 (71 ) 71 Other 44 (35 ) 9 38 (28 ) 10 Total Definite Lived Intangible Assets $2,260 ($1,373 ) $887 $2,039 ($1,163 ) $876 Total Identifiable Intangible Assets $3,418 ($1,373 ) $2,045 $3,146 ($1,163 ) $1,983 The Company’s identifiable intangible assets with definite lives are being amortized over their estimated useful lives. Aggregate amortization expense was $129 million , $121 million and $132 million in 2017 , 2016 and 2015 , respectively. ($ in millions) 2018 2019 2020 2021 2022 Estimated future amortization expense $125 $115 $105 $100 $100

Business Restructuring (Tables)

Business Restructuring (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Activity Related to Restructuring Reserves	2016 Restructuring and Associated Reserve Activity ($ in millions, except no. of employees) Severance and Other Costs Asset Write-offs Total Reserve Employees Impacted Performance Coatings $77 $45 $122 1,069 Industrial Coatings 52 14 66 804 Corporate 7 — 7 85 Total 2016 restructuring charge $136 $59 $195 1,958 2016 Activity (6 ) (59 ) (65 ) (40 ) December 31, 2016 $130 $— $130 1,918 2017 Activity (46 ) — (46 ) (969 ) Foreign currency impact 18 — 18 — December 31, 2017 $102 $— $102 949

Borrowings and Lines of Credit

Borrowings and Lines of Credit (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt and Bank Credit Agreements and Leases	Long-term Debt Obligations ($ in millions) Maturity Date 2017 2016 3-year variable rate bank loan (€500) 2017 $— $526 0.00% note (€300) 2019 358 313 2.3% notes 2019 299 298 3.6% notes 2020 497 496 9% non-callable debentures (1) 2021 133 133 0.875% notes (€600) 2022 716 626 0.875% note (€600) 2025 710 621 1.4% notes (€600) 2027 711 620 2.5% note (€80) 2029 95 83 7.70% notes 2038 174 174 5.5% notes 2040 247 247 3% note (€120) 2044 137 118 Various other non-U.S. debt (2) Various 43 41 Capital lease obligations Various 15 18 Impact of derivatives on debt (1) N/A 3 3 Total $4,138 $4,317 Less payments due within one year N/A 4 530 Long-term debt $4,134 $3,787 (1) PPG entered into several interest rate swaps which had the effect of converting fixed rate notes to variable rates, based on the three-month London Interbank Offered Rate (LIBOR). There were no interest rate swaps outstanding related to these instruments as of December 31, 2017 and 2016 . The impact of the derivatives on debt represents the fair value adjustment of the debt while the interest rate swaps were outstanding, which is being amortized as a reduction to interest expense over the remaining term of the debt. The weighted average effective interest rate for these borrowings, including the effects of the swaps, was 8.4% and 8.4% for the years ended December 31, 2017 and 2016 , respectively. Refer to Note 10, “Financial Instruments, Hedging Activities, and Fair Value Measurements” for additional information. (2) Weighted average interest rate of 3.7% and 3.8% as of December 31, 2017 and 2016 , respectively.
Schedule of Maturities of Long-term Debt	Long-term Debt Maturities ($ in millions) Maturity per year 2018 $4 2019 659 2020 497 2021 133 2022 718 Thereafter $2,127
Short-Term Debt Outstanding	Short-term Debt Obligations ($ in millions) 2017 2016 Various, weighted average 1.9% and 5.8% as of December 31, 2017 and 2016, respectively. $8 $99
Schedule of Future Minimum Rental Payments for Operating Leases	Minimum lease commitments for operating leases that have initial or remaining lease terms in excess of one year are as follows: ($ in millions) As of December 31, 2017 2018 $212 2019 167 2020 138 2021 86 2022 63 Beyond 2022 $174

Financial Instruments, Hedgin37

Financial Instruments, Hedging Activities and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value, Cash Flow and Net Investment Hedges	The following tables summarize the location and amount of gains (losses) related to derivative and debt financial instruments for the years ended December 31, 2017 , 2016 and 2015 . All dollar amounts are shown on a pre-tax basis. 2017 2016 2015 Caption in Consolidated Statement of Income ($ in millions) Loss Deferred in OCI Gain Recognized Gain (Loss) Deferred in OCI (Loss)/Gain Recognized Gain Deferred in OCI (Loss)/Gain Recognized Fair Value Foreign currency forward contracts — — — — — ($2 ) Sales Equity forward arrangements — — — — — (44 ) Asbestos - net Total Fair Value — — — — — ($46 ) Cash Flow Foreign currency forward contracts (a) ($7 ) $9 $1 ($5 ) $57 $50 Other charges and Cost of sales Total Cash Flow ($7 ) $9 $1 ($5 ) $57 $50 Net Investment Cross currency swaps ($61 ) $25 $77 Foreign denominated debt (403 ) 122 85 Foreign currency forward contracts — (14 ) 19 Total Net Investment ($464 ) $133 $181 Economic Foreign currency forward contracts $14 $14 $18 Other charges (a) The ineffective portion related to this item was $7 million , $9 million and $7 million of expense for the years ended December 31, 2017 , 2016 and 2015 , respectively.
Schedule of Derivative Liabilities at Fair Value	Assets and liabilities reported at fair value on a recurring basis December 31, 2017 December 31, 2016 ($ in millions) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Other current assets: Marketable equity securities $4 $— — $4 $— — Foreign currency forward contracts — 6 — — 22 — Cross currency swaps — 2 — — — — Other assets: Cross currency swaps — — — — $65 — Investments: Marketable equity securities $79 — — $78 — — Liabilities: Accounts payable and accrued liabilities: Foreign currency forward contracts — $23 — — $9 —
Schedule of Long-term Debt Instruments	Long-Term Debt ($ in millions) December 31, 2017 (a) December 31, 2016 (b) Long-term debt - carrying value $4,123 $4,299 Long-term debt - fair value $4,341 $4,502 (a) Excluding capital lease obligations of $15 million and short term borrowings of $8 million as of December 31, 2017 . (b) Excluding capital lease obligations of $18 million and short term borrowings of $99 million as of December 31, 2016 .

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Common Share Calculations	($ in millions, except per share amounts) 2017 2016 2015 As Restated As Restated Earnings per common share (attributable to PPG) Income from continuing operations, net of tax $1,369 $543 $1,311 Income from discontinued operations, net of tax 225 330 95 Net income (attributable to PPG) $1,594 $873 $1,406 Weighted average common shares outstanding 256.1 265.6 271.4 Effect of dilutive securities: Stock options 0.9 0.8 1.0 Other stock compensation plans 0.8 1.0 1.2 Potentially dilutive common shares 1.7 1.8 2.2 Adjusted weighted average common shares outstanding 257.8 267.4 273.6 Earnings per common share (attributable to PPG): Income from continuing operations, net of tax $5.34 $2.05 $4.83 Income from discontinued operations, net of tax 0.88 1.24 0.35 Net income (attributable to PPG) $6.22 $3.29 $5.18 Earnings per common share - assuming dilution (attributable to PPG) Income from continuing operations, net of tax $5.31 $2.04 $4.79 Income from discontinued operations, net of tax 0.87 1.23 0.35 Net income (attributable to PPG) $6.18 $3.27 $5.14

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Components of Income Tax Expense	The provision for income taxes by taxing jurisdiction and by significant components consisted of the following: ($ in millions) 2017 2016 2015 As Restated As Restated Current U.S. federal $179 ($251 ) $132 U.S. state and local 49 (12 ) 20 Foreign 349 306 261 Total current income tax expense $577 $43 $413 Deferred U.S. federal $107 $173 $31 U.S. state and local (16 ) (10 ) 6 Foreign (53 ) 8 (37 ) Total deferred income tax expense $38 $171 $— Total income tax expense $615 $214 $413
Reconciliation of Statutory U.S. Corporate Federal Income Tax Rate to Effective Income Tax Rate	A reconciliation of the statutory U.S. corporate federal income tax rate to the Company’s effective tax rate follows: 2017 2016 2015 As Restated As Restated U.S. federal income tax rate 35.0 % 35.0 % 35.0 % Changes in rate due to: U.S. tax cost - Tax Cuts & Jobs Act 11.0 — — U.S./foreign tax differential (9.3 ) (17.7 ) (8.2 ) U.S. current tax benefit on foreign exchange realization (4.9 ) (3.0 ) — U.S. tax incentives (2.3 ) (3.7 ) (1.9 ) U.S. tax (benefit) cost on foreign dividends (1.9 ) 0.4 (1.0 ) U.S. state and local taxes 1.1 (1.8 ) 1.0 U.S. deferred tax benefit on foreign income (0.6 ) (3.1 ) (4.1 ) Asbestos charge — 19.1 — Other 2.6 2.3 2.9 Effective income tax rate 30.7 % 27.5 % 23.7 %
Net deferred income tax assets and liabilities	($ in millions) 2017 2016 As Restated Deferred income tax assets related to Employee benefits $399 $606 Contingent and accrued liabilities 164 263 Operating loss and other carry-forwards 221 197 Inventories 6 14 Property 51 49 Other 135 100 Valuation allowance (173 ) (119 ) Total $803 $1,110 Deferred income tax liabilities related to Property $314 $349 Intangibles 578 647 Employee benefits 11 4 Derivatives 1 6 Undistributed foreign earnings 24 189 Other 20 146 Total $948 $1,341 Deferred income tax (liabilities) assets – net ($145 ) ($231 )
Summary of Operating Loss Carryforwards	($ in millions) 2017 2016 Expiration Available net operating loss carryforwards: Indefinite expiration $447 $376 NA Definite expiration 247 118 2018 - 2030 Total $694 $494 NA Net operating loss carryforwards, tax effected $210 $140 NA Income tax credit carryforwards $9 $57 2018 - 2027
Unrecognized Tax Benefits	A reconciliation of the total amounts of unrecognized tax benefits (excluding interest and penalties) as of December 31 follows: ($ in millions) 2017 2016 2015 January 1 $94 $82 $71 Current year tax positions - additions 37 25 14 Prior year tax positions - additions 26 8 5 Pre-acquisition unrecognized tax benefits — — 4 Prior year tax positions - reductions — (11 ) (3 ) Statute of limitations expirations (8 ) (8 ) (1 ) Settlements (10 ) — (3 ) Foreign currency translation 9 (2 ) (5 ) December 31 $148 $94 $82 Interest and penalties ($ in millions) 2017 2016 2015 Accrued interest and penalties related to unrecognized tax benefits $15 $9 $8 Loss recognized in income tax expense related to interest and penalties $4 $1 $2

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Changes in Projected Benefit Obligations, Plan Assets and Funded Status	The following table sets forth the changes in projected benefit obligations (“PBO”) (as calculated as of December 31), plan assets, the funded status and the amounts recognized in the accompanying consolidated balance sheet for the Company’s defined benefit pension and other postretirement benefit plans: Pensions Other Postretirement Benefits ($ in millions) 2017 2016 2017 2016 Projected benefit obligation, January 1 $3,252 $5,349 $792 $1,084 Service cost 33 48 10 15 Interest cost 98 142 24 31 Plan amendments — — — (306 ) Actuarial losses (gains) - net 185 538 (27 ) 13 Benefits paid (167 ) (233 ) (48 ) (53 ) Foreign currency translation adjustments 165 (141 ) 8 2 Settlements and curtailments (85 ) (2,354 ) — — Former glass business changes, net (1 ) (96 ) (8 ) 6 Other (18 ) (1 ) 2 — Projected benefit obligation, December 31 $3,462 $3,252 $753 $792 Market value of plan assets, January 1 $2,561 $4,627 Actual return on plan assets 289 470 Company contributions 87 204 Participant contributions 1 1 Benefits paid (109 ) (205 ) Plan transfers — (3 ) Plan settlements (95 ) (2,338 ) Plan expenses and other-net — — Foreign currency translation adjustments 149 (134 ) Former glass business changes, net — (61 ) Market value of plan assets, December 31 $2,883 $2,561 Funded Status ($579 ) ($691 ) ($753 ) ($792 ) Amounts recognized in the Consolidated Balance Sheet: Other assets (long-term) 173 110 — — Accounts payable and accrued liabilities (23 ) (61 ) (54 ) (61 ) Accrued pensions (729 ) (740 ) — — Other postretirement benefits — — (699 ) (724 ) Liabilities held for sale — — — (7 ) Net liability recognized ($579 ) ($691 ) ($753 ) ($792 ) The PBO is the actuarial present value of benefits attributable to employee service rendered to date, including the effects of estimated future pay increases. The accumulated benefit obligation (“ABO”) is the actuarial present value of benefits attributable to employee service rendered to date, but does not include the effects of estimated future pay increases. The ABO for all defined benefit pension plans as of December 31, 2017 and 2016 was $3,382 million and $3,171 million , respectively. The following table details the pension plans where the benefit liability exceeds the fair value of the plan assets: Pensions ($ in millions) 2017 2016 Plans with PBO in Excess of Plan Assets: Projected benefit obligation $2,544 $2,406 Fair value of plan assets $1,792 $1,609 Plans with ABO in Excess of Plan Assets: Accumulated benefit obligation $2,434 $2,302 Fair value of plan assets $1,749 $1,575
Accumulated Other Comprehensive Loss Pretax Amounts Not Yet Reflected in Net Periodic Benefit Cost	($ in millions) Pensions Other Postretirement Benefits 2017 2016 2017 2016 Accumulated net actuarial losses $835 $918 $180 $226 Accumulated prior service cost (credit) — 1 (239 ) (298 ) Total $835 $919 ($59 ) ($72 )
Change in Accumulated Other Comprehensive Loss (Pretax) Relating to Defined Benefit Pension and Other Postretirement Benefits	The net decrease in accumulated other comprehensive loss (pre-tax) in 2017 relating to defined benefit pension and other postretirement benefits is primarily attributable to pension settlement charges and other postretirement plan design changes, as follows: ($ in millions) Pensions Other Postretirement Benefits Net actuarial loss (gain) arising during the year $38 ($35 ) New prior service cost (credit) (2 ) 1 Amortization of actuarial loss (75 ) (12 ) Amortization of prior service (cost) credit (1 ) 59 Foreign currency translation adjustments 19 — Impact of settlements and curtailments (63 ) — Net change ($84 ) $13
Net Periodic Benefit Cost	Pensions Other Postretirement Benefits ($ in millions) 2017 2016 2015 2017 2016 2015 Service cost $33 $48 $57 $10 $15 $16 Interest cost 98 142 196 24 31 45 Expected return on plan assets (141 ) (213 ) (287 ) — — — Amortization of prior service credit — (1 ) (2 ) (59 ) (31 ) (9 ) Amortization of actuarial losses 75 110 119 12 19 32 Settlements, curtailments, and special termination benefits 60 1,015 8 — — — Net periodic benefit cost/(income) $125 $1,101 $91 ($13 ) $34 $84
Effect of One Percentage Point Increase or Decrease in Health Care Cost Trend Rates	If these 2018 health care cost trend rates were increased or decreased by one percentage point per year, such increase or decrease would have the following effects: One-Percentage Point ($ in millions) Increase Decrease Increase (decrease) in the aggregate of service and interest cost components of annual expense $1 ($1 ) Increase (decrease) in the benefit obligation $25 ($15 )
Schedule of Contributions to Defined benefit Plans	Contributions to defined benefit pension plans ($ in millions) 2017 2016 2015 U.S. defined benefit pension plans (a) $54 $134 $224 Non-U.S. defined benefit pension plans (b) $33 $54 $39 (a) During 2016 and 2015, U.S. contributions totaling $12 million and $26 million associated with the former glass segment were recast as cash flows from operations - discontinued operations and are excluded from the
Schedule of Expected Benefit Payments	The estimated benefits expected to be paid under the Company’s defined benefit pension and other postretirement benefit plans are: ($ in millions) Pensions Other Postretirement Benefits 2018 $147 $54 2019 $147 $54 2020 $156 $53 2021 $161 $53 2022 $166 $52 2023 to 2027 $901 $231
Weighted Average Target Pension Plan Asset Allocations	The following summarizes the weighted average target pension plan asset allocation as of December 31, 2017 and 2016 for all PPG defined benefit plans: Asset Category 2017 2016 Equity securities 15-45% 30-65% Debt securities 30-65% 30-65% Real estate 0-10% 0-10% Other 20-40% 0-20%
Fair Values of the Company's Pension Plan Assets by Asset Category	The fair values of the Company’s pension plan assets at December 31, 2017 and 2016 , by asset category, are as follows: December 31, 2017 December 31, 2016 ($ in millions) Level 1 (1) Level 2 (1) Level 3 (1) Total Level 1 (1) Level 2 (1) Level 3 (1) Total Asset Category Equity securities: U.S. Large cap $— $83 $— $83 $— $80 $— $80 Small cap 29 — — 29 — — — — PPG common stock — — — — 53 — — 53 Non-U.S. Developed and emerging markets (2) 115 79 — 194 80 75 — 155 Debt securities: Cash and cash equivalents — 11 — 11 — 6 — 6 Corporate (3) U.S. (4) — 201 86 287 — 5 86 91 Developed and emerging markets (2) — 43 — 43 — 42 — 42 Diversified (5) — 124 — 124 — 71 — 71 Government U.S. (4) 68 1 — 69 — — — — Developed markets — 101 — 101 — 78 — 78 Other (6) — 14 418 432 — — 15 15 Real estate, hedge funds, and other — 185 498 683 — 172 414 586 Total assets in the fair value hierarchy $212 $842 $1,002 $2,056 $133 $529 $515 $1,177 Common-collective trusts (7) — — — 827 — — — 1,384 Total Investments $212 $842 $1,002 $2,883 $133 $529 $515 $2,561 (1) These levels refer to the accounting guidance on fair value measurement described in Note 10, “Financial Instruments, Hedging Activities and Fair Value Measurements.” (2) These amounts represent holdings in investment grade debt or equity securities of issuers in both developed markets and emerging economies. (3) This category represents investment grade debt securities from a diverse set of industry issuers. (4) These investments are primarily long duration fixed income securities. (5) This category represents commingled funds invested in diverse portfolios of debt securities. (6) This category includes mortgage-backed and asset backed debt securities, municipal bonds and other debt securities including derivatives.
Change in the Fair Value of the Company's Level 3 Pension Assets	The change in the fair value of the Company’s Level 3 pension assets for the years ended December 31, 2017 and 2016 was as follows: ($ in millions) Real Estate Other Debt Securities Hedge Funds and Other Assets Total January 1, 2016 $209 $21 $405 $635 Realized gains 28 1 — 29 Unrealized losses (15 ) — (1 ) (16 ) Transfers (out)/in (88 ) (5 ) 16 (77 ) Foreign currency losses (5 ) (1 ) (50 ) (56 ) December 31, 2016 $129 $16 $370 $515 Realized gains 11 45 3 59 Unrealized losses — — 5 5 Transfers (out)/in (5 ) 355 36 386 Foreign currency loss 3 2 32 37 December 31, 2017 $138 $418 $446 $1,002
Benefit Obligations
Weighted Average Assumptions Used for the Defined Benefit Pension and Other Postretirement Plans	The following weighted average assumptions were used to determine the benefit obligation for the Company’s defined benefit pension and other postretirement plans as of December 31, 2017 and 2016 : 2017 2016 Discount rate (1) 3.2 % 3.7 % Rate of compensation increase 1.3 % 1.6 % (1) The discount rate for U.S. defined benefit pension and other postretirement plans was 3.7% and 4.3% as of December 31, 2017 and 2016 , respectively.
Benefit Costs
Weighted Average Assumptions Used for the Defined Benefit Pension and Other Postretirement Plans	The following weighted average assumptions were used to determine the net periodic benefit cost for the Company’s defined benefit pension and other postretirement benefit plans for the three years in the period ended December 31, 2017 : 2017 2016 2015 Discount rate 3.6 % 3.6 % 3.8 % Expected return on assets 5.4 % 6.1 % 6.1 % Rate of compensation increase 1.3 % 1.6 % 2.0 %

Commitments and Contingent Li41

Commitments and Contingent Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Accretion Of Future Funding Obligation	Consolidated Balance Sheet Asbestos Settlement Liability Equity Forward (Asset) Liability Pre-tax Charge ($ in millions) Current Long-term Balance as of and Activity for the year ended December 31, 2015 $796 $252 ($223 ) $12 Change in fair value: PPG stock 34 — — 34 Equity forward instrument — (35 ) (35 ) Accretion of asbestos liability — 6 — 6 Settlement of equity forward instrument with counterparty (a) — — (49 ) — Contribution of PCE shares and relinquishment of PC investment (15 ) — — — Contribution of 2,777,778 shares of PPG stock to the PC Trust (308 ) 308 Contribution of cash to the PC Trust (a) (506 ) (258 ) — Reclassification (1 ) — (1 ) — Balance as of and Activity for the year ended December 31, 2016 $— $— $— $5 (a) Cash outflows related to the asbestos settlement funding totaled $813 million in 2016.
Schedule of Loss Contingencies by Contingency	Environmental Reserves ($ in millions) 2017 2016 New Jersey Chrome $136 $163 Legacy glass and chemical 71 70 Other 51 52 Total $258 $285 Current Portion $73 $76
Environmental Costs	The pre-tax charges and cash outlays related to such environmental remediation in 2017 , 2016 and 2015 , were as follows: ($ in millions) 2017 2016 2015 New Jersey Chrome $4 $60 $— Other 6 34 9 Total $10 $94 $9 Cash outlays for environmental spending $44 $47 $109

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Summary of Shares Outstanding	Common Stock Treasury Stock Shares Outstanding January 1, 2015 581,146,136 (309,181,570 ) 271,964,566 Purchases — (6,992,772 ) (6,992,772 ) Issuances — 1,904,215 1,904,215 December 31, 2015 581,146,136 (314,270,127 ) 266,876,009 Purchases — (10,725,869 ) (10,725,869 ) Issuances — 1,180,020 1,180,020 December 31, 2016 581,146,136 (323,815,976 ) 257,330,160 Purchases — (7,427,557 ) (7,427,557 ) Issuances — 1,271,796 1,271,796 December 31, 2017 581,146,136 (329,971,737 ) 251,174,399

Accumulated Other Comprehensi43

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss ($ in millions) Unrealized Foreign Currency Translation Adjustments Pension and Other Postretirement Benefit Adjustments, net of tax (c) Unrealized Gain (Loss) on Derivatives, net of tax (d) Accumulated Other Comprehensive (Loss) Income January 1, 2015 ($628 ) ($1,492 ) $4 ($2,116 ) Current year deferrals to AOCI (a) (630 ) — — (630 ) Current year deferrals to AOCI, tax effected (b) (74 ) 9 41 (24 ) Reclassifications from AOCI to net income — 104 (36 ) 68 Period change ($704 ) $113 $5 ($586 ) December 31, 2015 ($1,332 ) ($1,379 ) $9 ($2,702 ) Current year deferrals to AOCI (a) (299 ) — — (299 ) Current year deferrals to AOCI, tax effected (b) (167 ) 29 3 (135 ) Reclassifications from AOCI to net income — 779 1 780 Period change ($466 ) $808 $4 $346 December 31, 2016 ($1,798 ) ($571 ) $13 ($2,356 ) Current year deferrals to AOCI (a) 542 — — 542 Current year deferrals to AOCI, tax effected (b) (311 ) 20 (4 ) (295 ) Reclassifications from AOCI to net income 58 (6 ) 52 Period change 231 78 (10 ) 299 December 31, 2017 ($1,567 ) ($493 ) $3 ($2,057 ) (a) Unrealized foreign currency translation adjustments related to translation of foreign denominated balance sheets are not presented net of tax given that no deferred U.S. income taxes have been provided on undistributed earnings of non-U.S. subsidiaries because they are deemed to be reinvested for an indefinite period of time. (b) The tax benefit (cost) related to unrealized foreign currency translation adjustments on tax inter-branch transactions and net investment hedges for the years ended December 31, 2017 , 2016 and 2015 was $141 million , $(34) million and $(84) million , respectively. In 2015, the balance includes a remeasurement of the tax cost on the foreign proceeds from the sale of the Company’s interest in Transitions Optical which have not been permanently reinvested. Refer to Note 3, “Acquisitions and Divestitures” for additional information. (c) The tax cost related to the adjustment for pension and other postretirement benefits for the years ended December 31, 2017 , 2016 and 2015 was $(33) million , $(403) million and $(51) million , respectively. Reclassifications from AOCI are included in the computation of net periodic benefit costs (See Note 13, “Employee Benefit Plans”). The cumulative tax benefit related to the adjustment for pension and other postretirement benefits at December 31, 2017 and 2016 was $243 million and $276 million , respectively. (d) The tax cost (benefit) related to the change in the unrealized gain on derivatives for the years ended December 31, 2017 , 2016 and 2015 was $5 million , $2 million and $(2) million , respectively. Reclassifications from AOCI are included in the gain or loss recognized on cash flow hedges (See Note 10 “Financial Instruments, Hedging Activities and Fair Value Measurements”).

Other Income (Tables)

Other Income (Tables)	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Components of Other Earnings	Other Income (As Restated) ($ in millions) 2017 2016 2015 As Restated As Restated Gain on disposals of ownership interests in business affiliates $25 $46 $— Royalty income 11 12 15 Share of net earnings of equity affiliates (See Note 6) 12 8 4 Gain on sale of assets 28 6 4 Income from a legal settlement 18 — — Other 56 55 87 Total $150 $127 $110

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation, Stock Options, Activity	($ in millions) 2017 2016 2015 As Restated As Restated Total stock-based compensation $35 $45 $54 Income tax benefit recognized $12 $17 $18
Weighted Average Assumptions Used in Calculating the Fair Value of Stock Option	The following weighted average assumptions were used to calculate the fair values of stock option grants in each year: 2017 2016 2015 Weighted average exercise price $101.53 $95.29 $118.02 Risk free interest rate 2.4 % 1.6 % 1.9 % Expected life of option in years 6.5 6.5 6.5 Expected dividend yield 1.8 % 2.1 % 2.7 % Expected volatility 22.0 % 22.8 % 29.2 %
Stock Options Outstanding, Exercisable and Activity	Stock Options Outstanding and Exercisable Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Intrinsic Value (in millions) Outstanding, January 1, 2016 3,881,566 $75.84 6.5 $86 Granted 642,037 $101.53 Exercised (856,900 ) $61.10 Forfeited/Expired (91,078 ) $101.36 Outstanding, December 31, 2017 3,575,625 $83.34 6.4 $120 Vested or expected to vest, December 31, 2017 3,530,023 $83.05 6.4 $120 Exercisable, December 31, 2017 1,677,087 $60.13 4.4 $95
Stock Option Activity	The following table presents stock option activity for the years ended December 31, 2017 , 2016 and 2015 : ($ in millions) 2017 2016 2015 Total intrinsic value of stock options exercised $40 $34 $92 Cash received from stock option exercises $52 $32 $53 Income tax benefit from the exercise of stock options $15 $12 $31 Total fair value of stock options vested $13 $16 $13
RSU Activity	RSU Activity Number of Shares Weighted Average Fair Value Intrinsic Value (in millions) Outstanding, January 1, 2017 721,924 $95.65 $69 Granted 229,667 $102.71 Additional shares vested 70,525 $114.08 Released from restrictions (349,871 ) $103.09 Forfeited (56,638 ) $89.16 Outstanding, December 31, 2017 615,607 $101.73 $63 Vested or expected to vest, December 31, 2017 595,462 $101.89 $60

Quarterly Financial Informati46

Quarterly Financial Information (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (unaudited)	Quarterly Financial Information (unaudited) (As Restated) 2017 Quarter Ended Full Year 2017 (1) ($ in millions, except per share amounts) March 31 June 30 September 30 December 31 Net sales $3,486 $3,804 $3,776 $3,682 $14,748 Cost of sales (2) 1,905 2,082 2,101 2,119 8,207 Net income (loss) attributable to PPG Continuing operations $331 $497 $393 $148 $1,369 Discontinued operations 6 (1 ) 217 3 225 Net income $337 $496 $610 $151 $1,594 Earnings per common share Continuing operations $1.29 $1.93 $1.53 $0.59 $5.34 Discontinued operations 0.02 — 0.85 0.01 0.88 Earnings per common share $1.31 $1.93 $2.38 $0.60 $6.22 Earnings per common share - assuming dilution Continuing operations $1.28 $1.92 $1.52 $0.58 $5.31 Discontinued operations 0.02 — 0.84 0.01 0.87 Earnings per common share – assuming dilution $1.30 $1.92 $2.36 $0.59 $6.18 2016 Quarter Ended Full Year 2016 (1) ($ in millions except per share amounts) March 31 June 30 September 30 December 31 Net sales $3,411 $3,782 $3,660 $3,417 $14,270 Cost of sales (2) 1,817 1,988 1,978 1,910 7,693 Net income (loss) attributable to PPG Continuing operations $328 $339 ($211 ) $87 $543 Discontinued operations 19 31 27 253 330 Net income (loss) $347 $370 ($184 ) $340 $873 Earnings (loss) per common share Continuing operations $1.23 $1.26 ($0.79 ) $0.34 $2.05 Discontinued operations 0.07 0.12 0.10 0.96 1.24 Earnings (loss) per common share $1.30 $1.38 ($0.69 ) $1.30 $3.29 Earnings (loss) per common share - assuming dilution Continuing operations $1.22 $1.25 ($0.79 ) $0.33 $2.04 Discontinued operations 0.07 0.12 0.10 0.96 1.23 Earnings (loss) per common share – assuming dilution $1.29 $1.37 ($0.69 ) $1.29 $3.27 (1) Full year earnings-per-share was calculated using the full year weighted average shares outstanding. As such, the sum of the quarters may not equal the total earnings-per-share for the year. (2) Exclusive of depreciation and amortization. Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $3,486 $— (a) $3,486 Selling, general and administrative 888 (6 ) (c) 882 Other charges 14 — (h) 14 Income from continuing operations before income taxes $440 $6 $446 Income tax expense 107 3 (j) 110 Income from continuing operations $333 $3 $336 Income from discontinued operations, net of tax 6 — 6 Net income attributable to the controlling and noncontrolling interests $339 $3 $342 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $334 $3 $337 Amounts attributable to PPG: Income from continuing operations, net of tax $328 $3 $331 Income from discontinued operations, net of tax 6 — 6 Net income (attributable to PPG) $334 $3 $337 Earnings per common share: Income from continuing operations, net of tax $1.28 $0.01 $1.29 Income from discontinued operations, net of tax 0.02 — 0.02 Net income (attributable to PPG) $1.30 $0.01 $1.31 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.27 $0.01 $1.28 Income from discontinued operations, net of tax 0.02 — 0.02 Net income (attributable to PPG) $1.29 $0.01 $1.30 Dividends per common share $0.40 $— $0.40 September 30, 2017 ($ in millions) As Previously Reported Restatement Adjustment Reference As Restated Assets Deferred income taxes $421 $1 (j) $422 Total $17,615 $1 $17,616 Liabilities and Shareholders’ Equity Current liabilities Accounts payable and accrued liabilities $3,895 $5 (a),(e),(f),(j) $3,900 Total current liabilities $4,618 $5 $4,623 Accrued pensions 758 1 (i) 759 Other liabilities 928 — (h) 928 Total liabilities $11,605 $6 $11,611 Shareholders’ equity Retained earnings 17,106 (5 ) 17,101 Total PPG shareholders’ equity $5,902 ($5 ) $5,897 Noncontrolling interests 108 108 Total shareholders’ equity $6,010 ($5 ) $6,005 Total $17,615 $1 $17,616 The net sales and income from discontinued operations related to the former Glass reportable business segment for the three and six months ended June 30, 2017 and 2016 were as follows: Three Months Ended Six Months Ended ($ in millions) 2017 2016 2017 2016 As Restated As Restated Net sales $84 $282 $167 $543 Income from operations $12 $43 $21 $71 Income tax expense 4 12 8 21 Income from discontinued operations, net of tax $8 $31 $13 $50 The net sales and income from discontinued operations related to the former Glass reportable business segment for the three and nine months ended September 30, 2017 and 2016 were as follows: Three Months Ended Nine Months Ended ($ in millions) 2017 2016 2017 2016 As Restated Net sales $50 $285 $217 $828 Income from operations $5 $38 $26 $109 Net gain on divestiture of North American fiber glass business 343 — 343 — Income tax expense 131 11 139 32 Income from discontinued operations, net of tax $217 $27 $230 $77 Stock-based compensation and the income tax benefit recognized during the three months ended March 31, 2017 were as follows: Three Months Ended ($ in millions) 2017 2016 As Restated Stock-based compensation $9 $10 Income tax benefit recognized $3 $4 Stock-based compensation and the income tax benefit recognized during the three and six months ended June 30, 2017 and 2016 were as follows: Three Months Ended Six Months Ended ($ in millions) 2017 2016 2017 2016 As Restated Stock-based compensation $8 $16 $17 $26 Income tax benefit recognized $2 $5 $5 $9 Stock-based compensation and the income tax benefit recognized during the three and nine months ended September 30, 2017 and 2016 were as follows: Three Months Ended Nine Months Ended ($ in millions) 2017 2016 2017 2016 As Restated Stock-based compensation $9 $11 $26 $37 Income tax benefit recognized $4 $3 $9 $12 Changes to shareholders’ equity for the three months ended March 31, 2017 were as follows: ($ in millions) Total PPG Shareholders’ Equity Non- controlling Interests Total Balance, January 1, 2017 $4,828 $87 $4,915 Net income 337 5 342 Other comprehensive income, net of tax 280 7 287 Cash dividends (103 ) — (103 ) Issuance of treasury stock 34 — 34 Stock repurchase program (163 ) — (163 ) Stock-based compensation activity (21 ) — (21 ) Other — (5 ) (5 ) Balance, March 31, 2017 $5,192 $94 $5,286 Changes to shareholders’ equity for the six months ended June 30, 2017 were as follows: ($ in millions) Total PPG Shareholders’ Equity Non- controlling Interests Total Balance, January 1, 2017 $4,828 $87 $4,915 Net income 833 10 843 Other comprehensive income, net of tax 297 13 310 Cash dividends (205 ) — (205 ) Issuance of treasury stock 49 — 49 Stock repurchase program (163 ) — (163 ) Stock-based compensation activity (16 ) — (16 ) Other — (5 ) (5 ) Balance, June 30, 2017 $5,623 $105 $5,728 Changes to shareholders’ equity for the nine months ended September 30, 2017 were as follows: ($ in millions) Total PPG Shareholders’ Equity Non-controlling Interests Total January 1, 2017 $4,828 $87 $4,915 Net income 1,443 16 1,459 Other comprehensive income, net of tax 293 15 308 Cash dividends (321 ) — (321 ) Issuance of treasury stock 75 — 75 Stock repurchase program (413 ) — (413 ) Stock-based compensation activity (8 ) — (8 ) Dividends paid on subsidiary common stock to noncontrolling interests — (5 ) (5 ) Other — (5 ) (5 ) September 30, 2017 $5,897 $108 $6,005 Quarterly Reportable Business Segment Information (As Restated) Three Months Ended ($ in millions) 2017 2016 As Restated Net sales: Performance Coatings $2,017 $2,039 Industrial Coatings 1,469 1,372 Total $3,486 $3,411 Segment income: Performance Coatings $284 $279 Industrial Coatings 273 265 Total $557 $544 Corporate (56 ) (63 ) Interest expense, net of interest income (21 ) (24 ) Legacy items (a) (8 ) (11 ) Pension settlement charge (22 ) — Transaction-related costs (b) (4 ) (2 ) Income from continuing operations before income taxes $446 $444 Three Months Ended Six Months Ended ($ in millions) 2017 2016 2017 2016 As Restated As Restated Net sales: Performance Coatings $2,299 $2,338 $4,316 $4,377 Industrial Coatings 1,505 1,444 2,974 2,816 Total $3,804 $3,782 $7,290 $7,193 Segment income: Performance Coatings $409 $428 $693 $707 Industrial Coatings 264 292 537 557 Total $673 $720 $1,230 $1,264 Corporate (32 ) (60 ) (88 ) (123 ) Interest expense, net of interest income (22 ) (24 ) (43 ) (48 ) Legacy items (a) 2 (10 ) (6 ) (21 ) Asset write-down — (10 ) — (10 ) Gain from the sale of an equity affiliate — 20 — 20 Pension settlement charge — — (22 ) — Gain from sale of a business 25 — 25 — Income from a legal settlement 18 — 18 — Transaction-related costs (b) (5 ) (6 ) (9 ) (8 ) Income from continuing operations before income taxes $659 $630 $1,105 $1,074 Three Months Ended Nine Months Ended ($ in millions) 2017 2016 2017 2016 As Restated As Restated Net sales: Performance Coatings $2,290 $2,223 $ 6,606 $6,600 Industrial Coatings 1,486 1,437 4,460 4,253 Total $3,776 $3,660 $11,066 $10,853 Segment income: Performance Coatings $366 $368 $1,059 $1,075 Industrial Coatings 223 249 760 806 Total $589 $617 $1,819 $1,881 Corporate (45 ) (43 ) (133 ) (166 ) Interest expense, net of interest income (22 ) (28 ) (65 ) (76 ) Legacy items (a) 1 (4 ) (5 ) (25 ) Asset write-down — — — (10 ) Gain from the sale of an equity affiliate — — — 20 Pension settlement charge — (968 ) (22 ) (968 ) Gain from sale of a business — — 25 — Income from a legal settlement — — 18 — Transaction-related costs (b) — — (9 ) (8 ) Income (loss) from continuing operations before income taxes $523 ($426 ) $1,628 $648 (a) Legacy items include current costs related to former operations of the Company, including pension and other postretirement benefit costs, certain charges for legal matters and environmental remediation costs, and certain other charges which are not associated with PPG's current business portfolio. (b) Transaction-related costs include advisory, legal, accounting, valuation and other professional or consulting fees incurred to effect significant acquisitions, as well as similar fees and other costs to effect disposals not classified as discontinued operations. These costs may also include the flow-through cost of sales for the step up to fair value of inventories acquired in acquisitions. These costs also include certain severance costs and charges associated with the Company's recent business portfolio transformation.
Condensed Income Statement	Quarterly Condensed Consolidated Statement of Income (unaudited) (As Restated) 2017 March 31 June 30 September 30 December 31 As Restated As Restated As Restated As Restated Net sales $3,486 $3,804 $3,776 $3,682 Cost of sales, exclusive of depreciation and amortization 1,905 2,082 2,101 2,119 Selling, general and administrative 882 872 902 908 Depreciation 79 81 85 86 Amortization 31 32 32 34 Research and development, net 110 113 114 116 Interest expense 25 26 27 27 Interest income (4 ) (4 ) (5 ) (7 ) Pension settlement charge 22 — — 38 Other charges 14 12 13 25 Other income (24 ) (69 ) (16 ) (41 ) Income from continuing operations before income taxes $446 $659 $523 $377 Income tax expense 110 157 124 224 Income from continuing operations $336 $502 $399 $153 Income from discontinued operations, net of tax 6 (1 ) 217 3 Net income attributable to the controlling and noncontrolling interests $342 $501 $616 $156 Less: Net income attributable to noncontrolling interests (5 ) (5 ) (6 ) (5 ) Net income (attributable to PPG) $337 $496 $610 $151 Amounts attributable to PPG: Income from continuing operations, net of tax $331 $497 $393 $148 Income (loss) from discontinued operations, net of tax 6 (1 ) 217 3 Net income (attributable to PPG) $337 $496 $610 $151 Earnings per common share: Income from continuing operations, net of tax $1.29 $1.93 $1.53 $0.59 Income (loss) from discontinued operations, net of tax 0.02 — 0.85 0.01 Net income (attributable to PPG) $1.31 $1.93 $2.38 $0.60 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.28 $1.92 $1.52 $0.58 Income (loss) from discontinued operations, net of tax 0.02 — 0.84 0.01 Net income (attributable to PPG) $1.30 $1.92 $2.36 $0.59 Dividends per common share $0.40 $0.40 $0.45 $0.45 Condensed Consolidated Statement of Income (unaudited) (As Restated) Six Months Ended June 30, 2017 Nine Months Ended September 30, 2017 As Restated As Restated Net sales $7,290 $11,066 Cost of sales, exclusive of depreciation and amortization 3,987 6,088 Selling, general and administrative 1,754 2,656 Depreciation 160 245 Amortization 63 95 Research and development, net 223 337 Interest expense 51 78 Interest income (8 ) (13 ) Pension settlement charge 22 22 Other charges 26 39 Other income (93 ) (109 ) Income from continuing operations before income taxes 1,105 1,628 Income tax expense 267 391 Income from continuing operations 838 1,237 Income from discontinued operations, net of tax 5 222 Net income attributable to the controlling and noncontrolling interests 843 1,459 Less: Net income attributable to noncontrolling interests 10 16 Net income (attributable to PPG) $833 $1,443 Amounts attributable to PPG: Income from continuing operations, net of tax $828 $1,221 Income from discontinued operations, net of tax 5 222 Net income (attributable to PPG) $833 $1,443 Earnings per common share: Income from continuing operations, net of tax $3.22 $4.75 Income from discontinued operations, net of tax 0.02 0.86 Net income (attributable to PPG) $3.24 $5.61 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $3.19 $4.72 Income from discontinued operations, net of tax 0.02 0.86 Net income (attributable to PPG) $3.21 $5.58 Dividends per common share $0.80 $1.25 Quarterly Condensed Consolidated Statement of Income (Unaudited) 2016 March 31 June 30 September 30 December 31 As Restated Net sales $3,411 $3,782 $3,660 $3,417 Cost of sales, exclusive of depreciation and amortization 1,817 1,988 1,978 1,910 Selling, general and administrative 897 930 893 868 Depreciation 79 79 82 79 Amortization 30 30 31 30 Research and development, net 114 115 115 115 Interest expense 31 31 34 29 Interest income (7 ) (7 ) (6 ) (6 ) Pension settlement charge — — 968 — Business restructuring — — — 191 Asbestos settlement, net 3 2 — — Other charges 17 29 12 117 Other income (14 ) (45 ) (21 ) (47 ) Income (loss) from continuing operations before income taxes $444 $630 ($426 ) $131 Income tax expense (benefit) 109 285 (220 ) 40 Income (loss) from continuing operations $335 $345 ($206 ) $91 Income from discontinued operations, net of tax 19 31 27 253 Net income (loss) attributable to the controlling and noncontrolling interests $354 $376 ($179 ) $344 Less: Net income attributable to noncontrolling interests (7 ) (6 ) (5 ) (4 ) Net income (loss) (attributable to PPG) $347 $370 ($184 ) $340 Amounts attributable to PPG: Income (loss) from continuing operations, net of tax $328 $339 ($211 ) $87 Income from discontinued operations, net of tax 19 31 27 253 Net income (loss) (attributable to PPG) $347 $370 ($184 ) $340 Earnings per common share: Income (loss) from continuing operations, net of tax $1.23 $1.26 ($0.79 ) $0.34 Income from discontinued operations, net of tax 0.07 0.12 0.10 0.96 Net income (loss) (attributable to PPG) $1.30 $1.38 ($0.69 ) $1.30 Earnings per common share – assuming dilution: Income (loss) from continuing operations, net of tax $1.22 $1.25 ($0.79 ) $0.33 Income from discontinued operations, net of tax 0.07 0.12 0.10 0.96 Net income (loss) (attributable to PPG) $1.29 $1.37 ($0.69 ) $1.29 Dividends per common share $0.36 $0.40 $0.40 $0.40 Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $3,806 ($2 ) (a) $3,804 Selling, general and administrative 865 7 (e),(f),(g) 872 Other income (72 ) 3 (b) (69 ) Income from continuing operations before income taxes $671 ($12 ) $659 Income tax expense 162 (5 ) (j) 157 Income from continuing operations $509 ($7 ) $502 Loss from discontinued operations, net of tax (3 ) 2 (b) (1 ) Net income attributable to the controlling and noncontrolling interests $506 ($5 ) $501 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $501 ($5 ) $496 Amounts attributable to PPG: Income from continuing operations, net of tax $504 ($7 ) $497 Loss from discontinued operations, net of tax (3 ) 2 (1 ) Net income (attributable to PPG) $501 ($5 ) $496 Earnings per common share: Income from continuing operations, net of tax $1.96 ($0.03 ) $1.93 Loss from discontinued operations, net of tax (0.01 ) 0.01 — Net income (attributable to PPG) $1.95 ($0.02 ) $1.93 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.95 ($0.03 ) $1.92 Loss from discontinued operations, net of tax (0.01 ) 0.01 — Net income (attributable to PPG) $1.94 ($0.02 ) $1.92 Dividends per common share $0.40 $— $0.40 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Six Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $7,292 ($2 ) (a) $7,290 Selling, general and administrative 1,753 1 (c),(e),(f),(g) 1,754 Other charges 26 — (h) 26 Other income (96 ) 3 (b) (93 ) Income from continuing operations before income taxes 1,111 $ (6 ) 1,105 Income tax expense 269 (2 ) (j) 267 Income from continuing operations 842 $ (4 ) 838 Income from discontinued operations, net of tax 3 2 (b) 5 Net income attributable to the controlling and noncontrolling interests $845 ($2 ) $843 Less: Net income attributable to noncontrolling interests (10 ) — (10 ) Net income (attributable to PPG) $835 ($2 ) $833 Amounts attributable to PPG: Income from continuing operations, net of tax $832 ($4 ) $828 Income from discontinued operations, net of tax 3 2 5 Net income (attributable to PPG) $835 ($2 ) $833 Earnings per common share: Income from continuing operations, net of tax $3.23 ($0.01 ) $3.22 Income from discontinued operations, net of tax 0.01 0.01 0.02 Net income (attributable to PPG) $3.24 $— $3.24 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $3.21 ($0.02 ) $3.19 Income from discontinued operations, net of tax 0.01 0.01 0.02 Net income (attributable to PPG) $3.22 ($0.01 ) $3.21 Dividends per common share $0.80 $— $0.80 Quarterly Condensed Consolidated Statement of Income (unaudited) - Summary of Restatement Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Cost of sales, exclusive of depreciation and amortization 2,100 1 (i) 2,101 Selling, general and administrative 905 (3 ) (e),(f),(g) 902 Income from continuing operations before income taxes $521 $2 $523 Income tax expense 123 1 (j) 124 Income from continuing operations $398 $1 $399 Income from discontinued operations, net of tax 217 — 217 Net income attributable to the controlling and noncontrolling interests $615 $1 $616 Less: Net income attributable to noncontrolling interests (6 ) — (6 ) Net income (attributable to PPG) $609 $1 $610 Amounts attributable to PPG: Income from continuing operations, net of tax $392 $1 $393 Income from discontinued operations, net of tax 217 — 217 Net income (attributable to PPG) $609 $1 $610 Earnings per common share: Income from continuing operations, net of tax $1.53 $— $1.53 Income from discontinued operations, net of tax 0.85 — 0.85 Net income (attributable to PPG) $2.38 $— $2.38 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $1.52 $— $1.52 Income from discontinued operations, net of tax 0.84 — 0.84 Net income (attributable to PPG) $2.36 $— $2.36 Dividends per common share $0.45 $— $0.45 Nine Months Ended As Previously Reported Restatement Adjustment Reference As Restated Net sales $11,068 ($2 ) (a) $11,066 Cost of sales, exclusive of depreciation and amortization 6,087 1 (i) 6,088 Selling, general and administrative 2,658 (2 ) (c),(e),(f) 2,656 Other charges 39 — (h) 39 Other income (112 ) 3 (b) (109 ) Income from continuing operations before income taxes $1,632 ($4 ) $1,628 Income tax expense 392 (1 ) (j) 391 Income from continuing operations $1,240 ($3 ) $1,237 Income from discontinued operations, net of tax 220 2 (b) 222 Net income attributable to the controlling and noncontrolling interests $1,460 ($1 ) $1,459 Less: Net income attributable to noncontrolling interests (16 ) — (16 ) Net income (attributable to PPG) $1,444 ($1 ) $1,443 Amounts attributable to PPG: Income from continuing operations, net of tax $1,224 ($3 ) $1,221 Income from discontinued operations, net of tax 220 2 222 Net income (attributable to PPG) $1,444 ($1 ) $1,443 Earnings per common share: Income from continuing operations, net of tax $4.76 ($0.01 ) $4.75 Income from discontinued operations, net of tax 0.86 — 0.86 Net income (attributable to PPG) $5.62 ($0.01 ) $5.61 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $4.73 ($0.01 ) $4.72 Income from discontinued operations, net of tax 0.85 0.01 0.86 Net income (attributable to PPG) $5.58 $— $5.58 Dividends per common share $1.25 $— $1.25 Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Cost of sales, exclusive of depreciation and amortization $2,117 $2 (b),(i) $2,119 Selling, general and administrative 912 (4 ) (e),(f) 908 Other income (42 ) 1 (b) (41 ) Income from continuing operations before income taxes $376 $1 $377 Income tax expense 224 — (j) 224 Income from continuing operations $152 $1 $153 Income from discontinued operations, net of tax — 3 (b) 3 Net income attributable to the controlling and noncontrolling interests $152 $4 $156 Less: Net income attributable to noncontrolling interests (5 ) — (5 ) Net income (attributable to PPG) $147 $4 $151 Amounts attributable to PPG: Income from continuing operations, net of tax $147 $1 $148 Income from discontinued operations, net of tax — 3 3 Net income (attributable to PPG) $147 $4 $151 Earnings per common share: Income from continuing operations, net of tax $0.58 $0.01 $0.59 Income from discontinued operations, net of tax — 0.01 0.01 Net income (attributable to PPG) $0.58 $0.02 $0.60 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $0.58 $— $0.58 Income from discontinued operations, net of tax — 0.01 0.01 Net income (attributable to PPG) $0.58 $0.01 $0.59 Dividends per common share $0.45 $— $0.45 Three Months Ended As Previously Reported Restatement Adjustment Reference As Restated Selling, general and administrative $861 $7 (c) $868 Business restructuring 195 (4 ) (d) 191 Other income (51 ) 4 (d) (47 ) Income from continuing operations before income taxes $138 ($7 ) $131 Income tax expense 43 (3 ) (j) 40 Income from continuing operations $95 ($4 ) $91 Income from discontinued operations, net of tax 253 — 253 Net income attributable to the controlling and noncontrolling interests $348 ($4 ) $344 Less: Net income attributable to noncontrolling interests (4 ) — (4 ) Net income (attributable to PPG) $344 ($4 ) $340 Amounts attributable to PPG: Income from continuing operations, net of tax $91 ($4 ) $87 Income from discontinued operations, net of tax 253 — 253 Net income (attributable to PPG) $344 ($4 ) $340 Earnings per common share: Income from continuing operations, net of tax $0.35 ($0.01 ) $0.34 Income from discontinued operations, net of tax 0.96 — 0.96 Net income (attributable to PPG) $1.31 ($0.01 ) $1.30 Earnings per common share – assuming dilution: Income from continuing operations, net of tax $0.34 ($0.01 ) $0.33 Income from discontinued operations, net of tax 0.96 — 0.96 Net income (attributable to PPG) $1.30 ($0.01 ) $1.29 Dividends per common share $0.40 $— $0.40
Condensed Statement of Comprehensive Income	Quarterly Condensed Consolidated Statement of Comprehensive Income (unaudited) (As Restated) 2017 Quarter Ended ($ in millions) March 31 June 30 September 30 Net income attributable to the controlling and noncontrolling interests $342 $501 $616 Defined benefit pension and other postretirement benefit adjustments 21 (55 ) (29 ) Unrealized foreign currency translation gains/(losses) 279 82 26 Unrealized (losses)/gains – derivative financial instruments (13 ) (4 ) 1 Other comprehensive income/(loss), net of tax 287 23 (2 ) Total comprehensive income $629 $524 $614 Less: amounts attributable to noncontrolling interests: Net income (5 ) (5 ) (6 ) Unrealized foreign currency translation losses (7 ) (6 ) (2 ) Comprehensive income attributable to PPG $617 $513 $606 ($ in millions) Six Months Ended June 30, 2017 Nine Months Ended September 30, 2017 Net income attributable to the controlling and noncontrolling interests $843 $1,459 Defined benefit pension and other postretirement benefit adjustments (34 ) (63 ) Unrealized foreign currency translation losses 361 387 Unrealized losses – derivative financial instruments (17 ) (16 ) Other comprehensive income, net of tax 310 308 Total comprehensive income $1,153 $1,767 Less: amounts attributable to noncontrolling interests: Net income (10 ) (16 ) Unrealized foreign currency translation losses (13 ) (15 ) Comprehensive income attributable to PPG $1,130 $1,736
Condensed Balance Sheet	Quarterly Condensed Consolidated Balance Sheets (unaudited) (As Restated) 2017 ($ in millions) March 31 June 30 September 30 December 31 Assets Current assets Cash and cash equivalents $1,349 $1,569 $2,287 $1,436 Short-term investments 40 48 41 55 Receivables 3,013 3,191 3,155 2,903 Inventories 1,699 1,766 1,805 1,730 Assets held for sale 223 177 — — Other 439 390 350 353 Total current assets $6,763 $7,141 $7,638 $6,477 Property, plant and equipment, net 2,659 2,710 2,730 2,824 Goodwill 3,720 3,845 3,881 3,942 Identifiable intangible assets, net 2,080 2,118 2,099 2,045 Deferred income taxes 170 321 422 305 Investments 175 256 261 268 Other assets 587 582 585 677 Total $16,154 $16,973 $17,616 $16,538 Liabilities and Shareholders’ Equity Current liabilities Accounts payable and accrued liabilities $3,517 $3,656 $3,900 $3,781 Restructuring reserves 95 115 107 102 Short-term debt and current portion of long-term debt 604 619 616 12 Liabilities held for sale 69 54 — — Total current liabilities $4,285 $4,444 $4,623 $3,895 Long-term debt 3,817 3,998 4,089 4,134 Accrued pensions 712 748 759 729 Other postretirement benefits 720 755 767 699 Deferred income taxes 400 390 445 442 Other liabilities 934 910 928 967 Total liabilities $10,868 $11,245 $11,611 $10,866 Commitments and contingent liabilities Shareholders’ equity Common stock $969 $969 $969 $969 Additional paid-in capital 711 723 745 756 Retained earnings 16,214 16,606 17,101 17,140 Treasury stock, at cost (10,626 ) (10,616 ) (10,855 ) (11,251 ) Accumulated other comprehensive loss (2,076 ) (2,059 ) (2,063 ) (2,057 ) Total PPG shareholders’ equity $5,192 $5,623 $5,897 $5,557 Noncontrolling interests 94 105 108 115 Total shareholders’ equity $5,286 $5,728 $6,005 $5,672 Total $16,154 $16,973 $17,616 $16,538
Condensed Cash Flow Statement	Quarterly Condensed Consolidated Statement of Cash Flows (unaudited) (As Restated) 2017 Year to Date ($ in millions) March 31 June 30 September 30 December 31 Operating activities Net income attributable to the controlling and noncontrolling interests $342 $843 $1,459 $1,615 Less: Income from discontinued operations 6 5 222 225 Income from continuing operations $336 $838 $1,237 $1,390 Adjustments to reconcile to cash from operations: Depreciation and amortization 110 223 340 460 Defined benefit pension expense 18 34 52 65 Pension settlement charge 22 22 22 60 Stock-based compensation expense 9 17 26 35 Net gain, from sale of businesses — (25 ) (25 ) (25 ) Equity affiliate (income)/loss, net of dividends (1 ) 3 — (4 ) Deferred income taxes 6 (40 ) (53 ) 38 Contributions to pension plans (34 ) (37 ) (43 ) (87 ) Restructuring payments (10 ) (20 ) (31 ) (49 ) Change in certain asset and liability accounts (net of acquisitions): Receivables (296 ) (406 ) (350 ) (76 ) Inventories (157 ) (185 ) (200 ) (116 ) Other current assets (47 ) (49 ) (40 ) (43 ) Accounts payable and accrued liabilities 62 147 229 188 Noncurrent assets and liabilities, net 39 (14 ) (102 ) (170 ) Taxes and interest payable (82 ) (128 ) (115 ) (129 ) Other 24 52 71 14 Cash (used for)/from operating activities - continuing operations ($1 ) $432 $1,018 1,551 Cash from operating activities - discontinued operations 10 14 14 17 Cash from operating activities $9 $446 $1,032 $1,568 Investing activities Capital expenditures ($63 ) ($135 ) ($207 ) ($360 ) Business acquisitions, net of cash balances acquired (61 ) (62 ) (69 ) (225 ) Payments for acquisition of equity investment — (100 ) (100 ) (100 ) Net proceeds from the sale of businesses — 52 593 593 Purchase of short-term investments — — — (1 ) Payments for the settlement of cross currency swap contracts (34 ) (34 ) (34 ) (34 ) Proceeds from the settlement of cross currency swap contracts 19 19 37 37 Other 2 2 — 27 Cash (used for)/from investing activities - continuing operations ($137 ) ($258 ) $220 ($63 ) Cash used for investing activities - discontinued operations (1 ) (3 ) (4 ) (4 ) Cash (used for)/from investing activities ($138 ) ($261 ) $216 ($67 ) Financing activities Net change in borrowings with maturities of three months or less ($7 ) ($3 ) ($6 ) ($7 ) Net payments on commercial paper and short-term debt (32 ) (61 ) (81 ) (93 ) Repayment of long-term debt (7 ) (8 ) (9 ) (588 ) Payments related to tax withholding on stock-based compensation awards (16 ) (20 ) (25 ) (28 ) Purchase of treasury stock (163 ) (163 ) (413 ) (813 ) Issuance of treasury stock 9 20 45 52 Dividends paid on PPG common stock (103 ) (205 ) (321 ) (434 ) Other (53 ) (50 ) (41 ) (43 ) Cash used for financing activities ($372 ) ($490 ) ($851 ) ($1,954 ) Effect of currency exchange rate changes on cash and cash equivalents 30 54 70 69 Net (decrease) increase in cash and cash equivalents ($471 ) ($251 ) $467 ($384 ) Cash and cash equivalents, beginning of year $1,820 $1,820 $1,820 $1,820 Cash and cash equivalents, end of period $1,349 $1,569 $2,287 $1,436 Supplemental disclosures of cash flow information: Interest paid, net of amount capitalized $23 $52 $60 $100 Taxes paid, net of refunds $90 $326 $481 $648

Reportable Business Segment I47

Reportable Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Reportable Business Segment	As Restated ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / (1) Consolidated Totals 2017 Net sales to external customers $8,730 $6,018 $ — $14,748 Intersegment net sales — — — — Total net sales $8,730 $6,018 $ — $14,748 Segment income $1,321 $972 $ — $2,293 Legacy items (2) (2 ) Pension settlement charge (60 ) Transaction-related costs (5) (9 ) Asset write-downs (7 ) Gain from sale of the Plaka business 25 Gain from a legal settlement 18 Gain from sale of a non-operating asset 13 Interest expense, net of interest income (85 ) Corporate unallocated (1) (181 ) Income before income taxes $2,005 Depreciation and amortization $272 $164 $24 $460 Share of net earnings (loss) of equity affiliates $2 $— $10 $12 Segment assets (3) $9,763 $4,563 $2,212 $16,538 Investment in equity affiliates $32 $13 $89 $134 Expenditures for property (including business acquisitions) $224 $328 $133 $685 As Restated ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / (1) Consolidated Totals 2016 Net sales to external customers $8,580 $5,690 $— $14,270 Intersegment net sales — 1 (1 ) — Total net sales $8,580 $5,691 ($1 ) $14,270 Segment income $1,314 $1,042 $— $2,356 Legacy items (2) (114 ) Business restructuring charge (191 ) Transaction-related costs (5) (8 ) Pension settlement charges (968 ) Asset write-downs (23 ) Gains on disposals of ownership interests in business affiliates 46 Interest expense, net of interest income (99 ) Corporate unallocated (1) (220 ) Income before income taxes $779 Depreciation and amortization $272 $143 $25 $440 Share of net earnings/(loss) of equity affiliates $5 $1 $2 $8 Segment assets (3) $9,168 $3,972 $2,631 $15,771 Investment in equity affiliates $30 $13 $3 $46 Expenditures for property (including business acquisitions) $187 $510 $32 $729 ($ in millions) Reportable Business Segments Performance Coatings Industrial Coatings Corporate / Eliminations / Non-Segment Items (1) Consolidated Totals 2015 Net sales to external customers $8,765 $5,476 $— $14,241 Intersegment net sales — 1 (1 ) — Total net sales $8,765 $5,477 ($1 ) $14,241 Segment income $1,302 $985 $— $2,287 Legacy items (2) (51 ) Business restructuring charge (136 ) Transaction-related costs (5) (44 ) Interest expense, net of interest income (86 ) Corporate unallocated (1) (225 ) Income before income taxes $1,745 Depreciation and amortization $296 $124 $26 $446 Share of net earnings of equity affiliates $7 $— ($3 ) $4 Segment assets (3) $9,917 $3,643 $3,516 $17,076 Investment in equity affiliates $45 $13 $36 $94 Expenditures for property (including business acquisitions) $298 $414 $38 $750
Geographic Information	($ in millions) Geographic Information 2017 2016 2015 Net sales (4) As Restated United States and Canada $6,307 $6,254 $6,232 Europe, Middle East and Africa (“EMEA”) 4,389 4,164 4,103 Asia Pacific 2,523 2,431 2,433 Latin America 1,529 1,421 1,473 Total $14,748 $14,270 $14,241 Segment income United States and Canada $1,129 $1,152 $1,176 EMEA 569 590 539 Asia Pacific 361 382 359 Latin America 234 232 213 Total $2,293 $2,356 $2,287 Property—net United States and Canada $1,224 $1,184 $1,101 EMEA 826 726 805 Asia Pacific 493 447 431 Latin America 281 251 271 Total $2,824 $2,608 $2,608 (1) Corporate intersegment net sales represent intersegment net sales eliminations. Corporate unallocated costs include the costs of corporate staff functions not directly associated with the operating segments, certain legal and insurance costs and stock-based compensation expense. (2) Legacy items include current costs related to former operations of the Company, including certain environmental remediation, pension and other postretirement benefit costs, legal costs and certain charges which are considered to be non-recurring. Until April 2016, legacy items also include equity earnings from PPG’s minority investment in Pittsburgh Glass Works, LLC. The Legacy items for 2016 include an environmental remediation pre-tax charge of $82 million . These charges relate to continued environmental remediation activities at legacy chemicals sites, primarily at PPG’s former Jersey City, N.J. chromium manufacturing plant and associated sites (Refer to Note 14, “Commitments and Contingent Liabilities”). (3) Segment assets are the total assets used in the operation of each segment. Corporate assets are principally cash and cash equivalents, cash held in escrow, short term investments, deferred tax assets and, until April 2016, PPG’s equity investment in it’s former automotive glass and services business. Non-segment items also includes the assets of businesses which have been reclassified as discontinued operations in the Consolidated Statement of Income. (Refer to Note 3, “Acquisitions and Divestitures”). (4) Net sales to external customers are attributed to geographic regions based upon the location of the operating unit shipping the product. (5) Transaction-related costs include advisory, legal, accounting, valuation, and other professional or consulting fees incurred to effect significant acquisitions, as well as similar fees and other costs to effect divestitures not classified as discontinued operations. These costs also include the flow-through cost of sales for the step up to fair value of inventory acquired in acquisitions.

Summary of Significant Accoun48

Summary of Significant Accounting Policies (Additional Information) (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Significant Accounting Policies [Line Items]
Advertising costs expensed											$ 313	$ 322	$ 324
Research and development – total											474	479	484
Less depreciation on research facilities											21	20	18
Research and development, net	$ 116	$ 114	$ 113	$ 110	$ 115	$ 115	$ 115	$ 114	$ 223	$ 337	453	459	$ 466
Asset retirement obligation	19				$ 18						19	$ 18
Other Commitment	$ 840										$ 840
Minimum
Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	20.00%										20.00%
Identifiable intangible assets with finite lives estimated useful lives											1 year
Maximum
Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	50.00%										50.00%
Identifiable intangible assets with finite lives estimated useful lives											30 years

Acquisitions and Dispositions49

Acquisitions and Dispositions (Acquistions) (Detail) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Jun. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jan. 31, 2018employeesstore	Jul. 31, 2016USD ($)	Dec. 31, 2013
Business Acquisition [Line Items]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290	$ 11,066	$ 14,748	$ 14,270	$ 14,241
Consideration paid for acquired entities, net of cash acquired, debt assumed, and other adjustments											74	$ 43	$ 371
The Crown Group
Business Acquisition [Line Items]
Net sales											$ 125
Taiwan Chlorine Industries (“TCI”)
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent	40.00%						40.00%				40.00%					60.00%
Business combination, recognized identifiable assets acquired and liabilities assumed, net	$ 100										$ 100
MetoKote Corporation
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, net															$ 306
Subsequent Event | ProCoatings
Business Acquisition [Line Items]
Number of stores | store														23
Entity number of employees | employees														100

Acquisitions and Dispositions50

Acquisitions and Dispositions (Summary of Purchase Price Allocations) (Details) - MetoKote Corporation part in Millions, $ in Millions	Jul. 31, 2016USD ($)part
Business Acquisition [Line Items]
Parts per day | part	1.5
Current assets	$ 38
Property, plant, and equipment	73
Identifiable intangible assets with finite lives	86
Goodwill	166
Deferred income taxes	(12)
Total assets	351
Current liabilities	(23)
Other long-term liabilities	(22)
Total liabilities	(45)
Total purchase price, net of cash acquired	$ 306

Acquisitions and Dispositions D

Acquisitions and Dispositions Divestitures (Details) $ in Millions	Sep. 01, 2017USD ($)	Jun. 30, 2017USD ($)	Nov. 30, 2016USD ($)Entity	Oct. 31, 2016USD ($)	Apr. 30, 2016USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Dec. 31, 2017USD ($)Segment	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Oct. 01, 2016USD ($)employee
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales						$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Net gains on the divestitures of businesses							0	25			0	0		25	$ 0	25	$ 0	25	46	0
Income tax expense						224	124	157	110	40	(220)	285	109	267		391		615	214	413
Income from discontinued operations, net of tax						151	610	496	337	340	(184)	370	347	833		1,443		1,594	873	1,406
Assets held for sale		$ 177				0	0	177	223	223				177		0		0	223
Liabilities held-for-sale		54				0	0	54	69	64				54		0		0	64
Pension settlement charge						$ 38	0	0	22	0	968	0	$ 0	22	0	22	968	60	968	0
Gain (loss) on sale of equity investments							$ 0	0	$ 0			20		25	20	$ 25	20	$ 25	39	0
Number of reportable business segments | Segment																		2
Pittsburgh Glass Works L L C
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sale of equity investments					$ 20
North American Fiber Glass Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gains on the divestitures of businesses	$ 343
Estimated proceeds from sale of business	$ 541
Entity number of employees							1,000									1,000
Sales revenue, goods, net																			350
Flat Glass Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gains on the divestitures of businesses				$ 421
Estimated proceeds from sale of business																					$ 740
Entity number of employees | employee																					1,200
Glass Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales							$ 50	84			285	282		167	543	$ 217	828	$ 217	908	1,089
Income from operations							5	12			38	43		21	71	26	109	30	111	137
Net gains on the divestitures of businesses							343				0					343	0	343	421	0
Income tax expense							131	4			11	12		8	21	139	32	140	202	42
Income from discontinued operations, net of tax							$ 217	$ 8			$ 27	$ 31		$ 13	$ 50	$ 230	$ 77	233	330	$ 95
Receivables. net										38									38
Inventory										32									32
Other current assets										1									1
Property, plant, and equipment, net										151									151
Deferred income taxes										30									30
Other non-current assets										1									1
Assets held for sale										193									193
Accounts payable and accrued liabilities										52									52
Long-term liabilities										12									12
Liabilities held-for-sale										$ 64									$ 64
European Fiber Glass
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gains on the divestitures of businesses				(42)
Pension settlement charge				$ 46
Fiber Glass Asian Joint Ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest			50.00%
Number of joint ventures disposed | Entity			2
Gain (loss) on sale of equity investments			$ 36
Mexican Plaka Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gains on the divestitures of businesses		$ 25																$ 25

Restatement of Previously Rep52

Restatement of Previously Reported Consolidated Annual Financial Statements - Background (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended									6 Months Ended			9 Months Ended		12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Discontinued operations (in dollars per share)		$ 3	$ 217	$ (1)	$ 6	$ 253	$ 27	$ 31	$ 19		$ 5		$ 222		$ 225	$ 330	$ 95
Other charges		25	13	12	14	117	12	29	17		26		39		64	175	90
Amortization		34	32	32	31	30	31	30	30		63		95		129	121	132
Inventories					(157)						(185)		(200)		(116)	56	37
Income (loss) from continuing operations before income taxes, noncontrolling interest		$ (377)	(523)	$ (659)	(446)	$ (131)	426	$ (630)	$ (444)		(1,105)	$ (1,074)	(1,628)	$ (648)	(2,005)	(779)	(1,745)
Defined benefit pension expense					$ 18						$ 34		52		$ 65	$ 85	$ 88
Share-based compensation expense			$ 9				$ 11						$ 26	$ 37
Discontinued operations (in dollars per share)		$ 0.01	$ 0.84	$ 0	$ 0.02	$ 0.96	$ 0.10	$ 0.12	$ 0.07		$ 0.02		$ 0.86		$ 0.87	$ 1.23	$ 0.35
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Discontinued operations (in dollars per share)		$ 3	$ 0	$ 2	$ 0	$ 0					$ 2		$ 2		$ 5	$ 0
Other charges					0						0		0		0
Income (loss) from continuing operations before income taxes, noncontrolling interest		(1)	(2)	12	(6)	7					6		4		3	7
Prior period reclassification adjustment, discontinued operations to continuing operations		4.7		2.5
Compensation										$ 3.5
Accrued expenses, healthcare			3.5										3.5
Accrued vacation		2.2	(1.3)	$ (0.9)						$ 2.2	$ (0.9)		$ (1.3)		$ 2.2
Defined benefit pension expense		$ 1	$ 1
Restructuring reserve, accrual adjustment						3.4										$ 3.4
Share-based compensation expense					$ 6.8	$ (6.8)
Discontinued operations (in dollars per share)		$ 0.01	$ 0	$ 0.01	$ 0	$ 0					$ 0.01		$ 0.01		$ 0.02	$ 0
Restatement Adjustment | Share-based Compensation
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest					$ 6.8	$ 6.8										$ 6.8
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Discontinued operations (in dollars per share)		$ 0	$ 217	$ (3)	6	253					$ 3		$ 220		$ 220	330
Other charges					14						26		39		64
Income (loss) from continuing operations before income taxes, noncontrolling interest		$ (376)	$ (521)	$ (671)	$ (440)	$ (138)					$ (1,111)		$ (1,632)		$ (2,008)	$ (786)
Discontinued operations (in dollars per share)		$ 0	$ 0.84	$ (0.01)	$ 0.02	$ 0.96					$ 0.01		$ 0.85		$ 0.85	$ 1.23
Inadvertent Errors | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest															$ 2.3
Subsequent Event | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating expenses	$ 1.4
Other charges	5
Amortization	1.4
Increase (decrease) in health care insurance liabilities	0.5
Income (loss) from continuing operations before income taxes, noncontrolling interest	5.7
Subsequent Event | Restatement Adjustment | EMEA
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Inventories	(2.2)
Subsequent Event | Under Amortized Amortization Expense, Understatement of Accrued Liability, Inventory Adjustment | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest	$ (0.3)

Restatement of Previously Rep53

Restatement of Previously Reported Consolidated Annual Financial Statements - Impact Of The Restatement (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations, net of tax, attributable to parent	$ (148)	$ (393)	$ (497)	$ (331)	$ (87)	$ 211	$ (339)	$ (328)	$ (828)		$ (1,221)		$ (1,369)	$ (543)	$ (1,311)
Continuing operations (in dollars per share)	$ (0.58)	$ (1.52)	$ (1.92)	$ (1.28)	$ (0.33)	$ 0.79	$ (1.25)	$ (1.22)	$ (3.19)		$ (4.72)		$ (5.31)	$ (2.04)	$ (4.79)
Other charges	$ 25	$ 13	$ 12	$ 14	$ 117	$ 12	$ 29	$ 17	$ 26		$ 39		$ 64	$ 175	$ 90
Income (loss) from continuing operations before income taxes, noncontrolling interest	377	523	659	446	131	(426)	630	444	1,105	$ 1,074	1,628	$ 648	2,005	779	1,745
Environmental remediation charge													0	82	0
Discontinued operations (in dollars per share)	3	217	(1)	$ 6	$ 253	$ 27	$ 31	$ 19	5		222		225	330	$ 95
Earned payout if the target performance is achieved				150.00%	100.00%	150.00%
Share-based compensation expense		9				$ 11					26	$ 37
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations, net of tax, attributable to parent	$ (1)	$ (1)	$ 7	$ (3)	$ 4				$ 4		$ 3		$ 2	$ 4
Continuing operations (in dollars per share)	$ 0	$ 0	$ 0.03	$ (0.01)	$ 0.01				$ 0.02		$ 0.01		$ 0.01	$ 0.01
Other charges				$ 0					$ 0		$ 0		$ 0
Income (loss) from continuing operations before income taxes, noncontrolling interest	$ 1	$ 2	$ (12)	6	$ (7)				(6)		(4)		(3)	$ (7)
Environmental remediation charge				0.5									0.5
Prior period reclassification adjustment, discontinued operations to continuing operations	4.7		2.5
Discontinued operations (in dollars per share)	$ 3	$ 0	$ 2	0	0				$ 2		$ 2		5	0
Restructuring reserve, accrual adjustment					3.4									3.4
Share-based compensation expense				6.8	(6.8)
Share-based Compensation | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest				(6.8)	$ (6.8)									$ (6.8)
Other Expense
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Environmental remediation charge				0.5									0.5
Under Reported Customer Rebates | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest													1.8
Incorrect Share Based Compensation Payout Assumptions | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest				$ (6.8)
Glass Segment | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income (loss) from continuing operations before income taxes, noncontrolling interest													7.2
Discontinued operations (in dollars per share)													$ 4.5

Restatement of Previously Rep54

Restatement of Previously Reported Consolidated Annual Financial Statements - Summary of Restatement - Statement of Income (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	2,119	2,101	2,082	1,905	1,910	1,978	1,988	1,817	3,987		6,088		8,207	7,693	7,786
Selling, general and administrative	908	902	872	882	868	893	930	897	1,754		2,656		3,564	3,588	3,584
Other charges	25	13	12	14	117	12	29	17	26		39		64	175	90
Other income	(41)	(16)	(69)	(24)	(47)	(21)	(45)	(14)	(93)		(109)		(150)	(127)	(110)
Business restructuring					191	0	0	0					0	191	136
Income before income taxes	377	523	659	446	131	(426)	630	444	1,105	$ 1,074	1,628	$ 648	2,005	779	1,745
Income tax expense	224	124	157	110	40	(220)	285	109	267		391		615	214	413
Income from continuing operations	153	399	502	336	91	(206)	345	335	838		1,237		1,390	565	1,332
Income from discontinued operations, net of tax	3	217	(1)	6	253	27	31	19	5		222		225	330	95
Net income attributable to the controlling and noncontrolling interests	156	616	501	342	344	(179)	376	354	843		1,459		1,615	895	1,427
Less: net income attributable to noncontrolling interests	5	6	5	5	4	5	6	7	10		16		21	22	21
Net income (attributable to PPG)	151	610	496	337	340	(184)	370	347	833		1,443		1,594	873	1,406
Continuing operations (in dollars per share)	148	393	497	331	87	(211)	339	328	828		1,221		1,369	543	1,311
Discontinued operations (in dollars per share)	$ 3	$ 217	$ (1)	$ 6	$ 253	$ 27	$ 31	$ 19	$ 5		$ 222		$ 225	$ 330	$ 95
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22		$ 4.75		$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.88	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24		5.61		6.22	3.29	5.18
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19		4.72		5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.87	1.23	0.35
Net Income (attributable to PPG) (in dollars per share)	0.59	2.36	1.92	1.30	1.29	(0.69)	1.37	1.29	3.21		5.58		$ 6.18	$ 3.27	$ 5.14
Common stock, dividends, per share, declared	$ 0.45	$ 0.45	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.36	$ 0.80		$ 1.25
As Previously Reported
Net sales			$ 3,806	$ 3,486					$ 7,292		$ 11,068		$ 14,750
Cost of sales, exclusive of depreciation and amortization	$ 2,117	$ 2,100									6,087		8,204
Selling, general and administrative	912	905	865	888	$ 861				1,753		2,658		3,570	$ 3,581
Other charges				14					26		39		64
Other income	(42)		(72)		(51)				(96)		(112)		(154)	(131)
Business restructuring					195									195
Income before income taxes	376	521	671	440	138				1,111		1,632		2,008	786
Income tax expense	224	123	162	107	43				269		392		616	217
Income from continuing operations	152	398	509	333	95				842		1,240		1,392	569
Income from discontinued operations, net of tax	0	217	(3)	6	253				3		220		220	330
Net income attributable to the controlling and noncontrolling interests	152	615	506	339	348				845		1,460		1,612	899
Less: net income attributable to noncontrolling interests	(5)	(6)	(5)	(5)	(4)				(10)		(16)		21	22
Net income (attributable to PPG)	147	609	501	334	344				835		1,444		1,591	877
Continuing operations (in dollars per share)	147	392	504	328	91				832		1,224		1,371	547
Discontinued operations (in dollars per share)	$ 0	$ 217	$ (3)	$ 6	$ 253				$ 3		$ 220		$ 220	$ 330
Continuing operations (in dollars per share)	$ 0.58	$ 1.53	$ 1.96	$ 1.28	$ 0.35				$ 3.23		$ 4.76		$ 5.35	$ 2.06
Discontinued operations (in dollars per share)	0	0.85	(0.01)	0.02	0.96				0.01		0.86		0.86	1.24
Net Income (attributable to PPG) (in dollars per share)	0.58	2.38	1.95	1.30	1.31				3.24		5.62		6.21	3.30
Continuing operations (in dollars per share)	0.58	1.52	1.95	1.27	0.34				3.21		4.73		5.32	2.05
Discontinued operations (in dollars per share)	0	0.84	(0.01)	0.02	0.96				0.01		0.85		0.85	1.23
Net Income (attributable to PPG) (in dollars per share)	0.58	2.36	1.94	1.29	1.30				3.22		5.58		$ 6.17	$ 3.28
Common stock, dividends, per share, declared	$ 0.45	$ 0.45	$ 0.40	$ 0.40	$ 0.40				$ 0.80		$ 1.25
Restatement Adjustment
Net sales			$ (2)	$ 0					$ (2)		$ (2)		$ (2)
Cost of sales, exclusive of depreciation and amortization	$ 2	$ 1									1		3
Selling, general and administrative	(4)	(3)	7	(6)	$ 7				1		(2)		(6)	$ 7
Other charges				0					0		0		0
Other income	1		3		4				3		3		4	4
Business restructuring					(4)									(4)
Income before income taxes	1	2	(12)	6	(7)				(6)		(4)		(3)	(7)
Income tax expense	0	1	(5)	3	(3)				(2)		(1)		(1)	(3)
Income from continuing operations	1	1	(7)	3	(4)				(4)		(3)		(2)	(4)
Income from discontinued operations, net of tax	3	0	2	0	0				2		2		5	0
Net income attributable to the controlling and noncontrolling interests	4	1	(5)	3	(4)				(2)		(1)		3	(4)
Less: net income attributable to noncontrolling interests	0	0	0	0	0				0		0		0	0
Net income (attributable to PPG)	4	1	(5)	3	(4)				(2)		(1)		3	(4)
Continuing operations (in dollars per share)	1	1	(7)	3	(4)				(4)		(3)		(2)	(4)
Discontinued operations (in dollars per share)	$ 3	$ 0	$ 2	$ 0	$ 0				$ 2		$ 2		$ 5	$ 0
Continuing operations (in dollars per share)	$ 0.01	$ 0	$ (0.03)	$ 0.01	$ (0.01)				$ (0.01)		$ (0.01)		$ (0.01)	$ (0.01)
Discontinued operations (in dollars per share)	0.01	0	0.01	0	0				0.01		0		0.02	0
Net Income (attributable to PPG) (in dollars per share)	0.02	0	(0.02)	0.01	(0.01)				0		(0.01)		0.01	(0.01)
Continuing operations (in dollars per share)	0	0	(0.03)	0.01	(0.01)				(0.02)		(0.01)		(0.01)	(0.01)
Discontinued operations (in dollars per share)	0.01	0	0.01	0	0				0.01		0.01		0.02	0
Net Income (attributable to PPG) (in dollars per share)	0.01	0	(0.02)	0.01	(0.01)				(0.01)		0		$ 0.01	$ (0.01)
Common stock, dividends, per share, declared	$ 0	$ 0	$ 0	$ 0	$ 0				$ 0		$ 0

Restatement of Previously Rep55

Restatement of Previously Reported Consolidated Annual Financial Statements - Summary of Restatement - Statement of Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income attributable to the controlling and noncontrolling interests	$ 156	$ 616	$ 501	$ 342	$ 344	$ (179)	$ 376	$ 354	$ 843	$ 1,459	$ 1,615	$ 895	$ 1,427
Unrealized foreign currency translation gains/(losses)		(29)	(55)	21					(34)	(63)	248	(476)	(717)
Defined benefit pension and other postretirement benefit adjustments		26	82	279					361	387	78	808	113
Unrealized (losses)/gains – derivative financial instruments		1	(4)	(13)					(17)	(16)	(10)	4	5
Other comprehensive income/(loss), net of tax		(2)	23	287					310	308	316	336	(599)
Total comprehensive income		614	524	629					1,153	1,767	1,931	1,231	828
Net income	(5)	(6)	(5)	(5)	(4)	$ (5)	$ (6)	$ (7)	(10)	(16)	(21)	(22)	(21)
Unrealized foreign currency translation (losses)/gains		(2)	(6)	(7)					(13)	(15)	(17)	10	13
Comprehensive income attributable to PPG		606	513	617					1,130	1,736	1,893	1,219	$ 820
As Previously Reported
Net income attributable to the controlling and noncontrolling interests	152	615	506	339	348				845	1,460	1,612	899
Unrealized foreign currency translation gains/(losses)											248	(476)
Defined benefit pension and other postretirement benefit adjustments											78	808
Unrealized (losses)/gains – derivative financial instruments											(10)	4
Other comprehensive income/(loss), net of tax											316	336
Total comprehensive income											1,928	1,235
Net income	5	6	5	5	4				10	16	(21)	(22)
Unrealized foreign currency translation (losses)/gains											(17)	10
Comprehensive income attributable to PPG											1,890	1,223
Restatement Adjustment
Net income attributable to the controlling and noncontrolling interests	4	1	(5)	3	(4)				(2)	(1)	3	(4)
Total comprehensive income											3	(4)
Net income	$ 0	$ 0	$ 0	$ 0	$ 0				$ 0	$ 0	0	0
Comprehensive income attributable to PPG											$ 3	$ (4)

Restatement of Previously Rep56

Restatement of Previously Reported Consolidated Annual Financial Statements - Summary of Restatement - Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred income taxes	$ 803				$ 1,110
Deferred income taxes	305	$ 422	$ 321	$ 170	186
Total Assets	16,538	17,616	16,973	16,154	15,771
Accounts payable and accrued liabilities	3,781	3,900	3,656	3,517	3,460
Total current liabilities	3,895	4,623	4,444	4,285	4,253
Total liabilities	10,866	11,611	11,245	10,868	10,856
Additional paid-in capital	756	745	723	711	707
Retained earnings	17,140	17,101	16,606	16,214	15,980
Total PPG shareholders’ equity	5,557	5,897	5,623	5,192	4,828
Noncontrolling interests	115	108	105	94	87
Total shareholders’ equity	5,672	6,005	5,728	5,286	4,915	$ 5,069	$ 5,265
Total	16,538	17,616	16,973	$ 16,154	15,771
As Previously Reported
Deferred income taxes		421			184
Total Assets		17,615	16,977		15,769
Accounts payable and accrued liabilities	3,780	3,895	3,653
Total current liabilities	3,894	4,618	4,441
Total liabilities	10,865	11,605	11,242
Additional paid-in capital					701
Retained earnings	17,141	17,106	16,613		15,984
Total PPG shareholders’ equity	5,558	5,902	5,630		4,826
Noncontrolling interests	115	108	105		87
Total shareholders’ equity	5,673	6,010	5,735		4,913
Total	16,538	17,615	16,977		15,769
Restatement Adjustment
Deferred income taxes		1			2
Total Assets		1	(4)		2
Accounts payable and accrued liabilities	1	5	3
Total current liabilities	1	5	3
Total liabilities	1	6	3
Additional paid-in capital					6
Retained earnings	(1)	(5)	(7)		(4)
Total PPG shareholders’ equity	(1)	(5)	(7)		2
Noncontrolling interests	0
Total shareholders’ equity	(1)	(5)	(7)
Total	$ 0	$ 1	$ (4)		$ 2

Working Capital Detail (Detail)

Working Capital Detail (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Disclosure Components Of Working Capital Detail [Abstract]
Trade - net	$ 2,559				$ 2,288
Equity affiliates	5				2
Other - net	339				364
Total	2,903	$ 3,155	$ 3,191	$ 3,013	2,654
Finished products	1,083				947
Work in process	177				165
Raw materials	437				370
Supplies	33				32
Total	1,730	1,805	1,766	1,699	1,514
Trade	2,321				1,907
Accrued payroll	441				443
Customer rebates	261				235
Other postretirement and pension benefits	78				124
Income taxes	100				94
Other	580				657
Total	$ 3,781	$ 3,900	$ 3,656	$ 3,517	$ 3,460

Working Capital Detail (Additio

Working Capital Detail (Additional Information) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Disclosure Components Of Working Capital Detail [Abstract]
Allowance for doubtful accounts	$ 25	$ 36
Percentage of inventories valued using the LIFO method	34.00%	38.00%
FIFO adjustment	$ 103	$ 106
Effect of LIFO on earnings, income	$ 0	$ 2

Property, Plant and Equipment59

Property, Plant and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 6,594	$ 6,005
Accumulated depreciation, depletion and amortization, property, plant, and equipment	3,770	3,397
Property, plant and equipment, net	2,824	2,608	$ 2,608	$ 2,730	$ 2,710	$ 2,659
Capitalized interest	7	8	$ 9
Land and land improvements
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 487	451
Land and land improvements | Minimum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	1 year
Land and land improvements | Maximum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	30 years
Buildings
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 1,488	1,324
Buildings | Minimum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	20 years
Buildings | Maximum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	40 years
Machinery and equipment
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 3,432	3,076
Machinery and equipment | Minimum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	5 years
Machinery and equipment | Maximum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	25 years
Other
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 958	774
Other | Minimum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	3 years
Other | Maximum
Property, Plant, and Equipment Disclosure [Line Items]
Property useful lives	20 years
Construction in progress
Property, Plant, and Equipment Disclosure [Line Items]
Property	$ 229	$ 380

Investments (Detail)

Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	$ 268	$ 261	$ 256	$ 175	$ 179
Investments in equity affiliates
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	135				46
Marketable equity securities - Trading (See Note 9) | Trading Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	79				78
Other
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	$ 54				$ 55

Investments (Additional Informa

Investments (Additional Information) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016	Dec. 31, 2013
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Equity in undistributed earnings losses of subsidiaries	$ 12	$ 7
Proceeds from dividends received	$ 8	$ 7	$ 77
Taiwan Chlorine Industries (“TCI”)
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Noncontrolling interest, ownership percentage by parent	40.00%			40.00%	60.00%
Investments In Other Operating Joint Venture
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Percentage of ownership interests	50.00%

Goodwill and Other Identifiab62

Goodwill and Other Identifiable Intangible Assets (Carrying Amount of Goodwill Attributable to Each Reportable Segment) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Beginning Balance	$ 3,572	$ 3,625
Goodwill from acquisitions	112	174
Currency translation	258	(227)
Ending Balance	3,942	3,572
Performance Coatings Segment
Goodwill [Roll Forward]
Beginning Balance	2,870	3,073
Goodwill from acquisitions	23	6
Currency translation	211	(209)
Ending Balance	3,104	2,870
Industrial Coatings Segment
Goodwill [Roll Forward]
Beginning Balance	702	552
Goodwill from acquisitions	89	168
Currency translation	47	(18)
Ending Balance	$ 838	$ 702

Goodwill and Other Identifiab63

Goodwill and Other Identifiable Intangible Assets (Identifiable Intangible Assets with Finite Lives) (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Acquired Finite-Lived Intangible Assets [Line Items]
Carrying amount of acquired trademarks with indefinite lives	$ 1,158				$ 1,107						$ 1,158	$ 1,107
Gross carrying amount	2,260				2,039						2,260	2,039
Accumulated amortization	(1,373)				(1,163)						(1,373)	(1,163)
Net	887				876						887	876
Intangible assets, gross (excluding goodwill)	3,418				3,146						3,418	3,146
Intangible assets, accumulated amortization (excluding goodwill)					1,163							1,163
Total Identifiable Intangible Assets	2,045	$ 2,099	$ 2,118	$ 2,080	1,983				$ 2,118	$ 2,099	2,045	1,983
Aggregate amortization expense of identifiable intangible assets	34	$ 32	$ 32	$ 31	30	$ 31	$ 30	$ 30	$ 63	$ 95	129	121	$ 132
Estimated future amortization of identifiable intangible assets in 2018	125										125
Estimated future amortization of identifiable intangible assets in 2019	115										115
Estimated future amortization of identifiable intangible assets in 2020	105										105
Estimated future amortization of identifiable intangible assets in 2021	100										100
Estimated future amortization of identifiable intangible assets in 2022	100										100
Acquired technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	613				587						613	587
Accumulated amortization	(489)				(446)						(489)	(446)
Net	124				141						124	141
Customer-related
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,437				1,272						1,437	1,272
Accumulated amortization	(762)				(618)						(762)	(618)
Net	675				654						675	654
Tradenames
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	166				142						166	142
Accumulated amortization	(87)				(71)						(87)	(71)
Net	79				71						79	71
Other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	44				38						44	38
Accumulated amortization	(35)				(28)						(35)	(28)
Net	$ 9				$ 10						$ 9	$ 10

Business Restructuring (Additio

Business Restructuring (Additional Information) (Detail)	3 Months Ended				12 Months Ended
	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2017USD ($)employee	Dec. 31, 2016USD ($)employee	Dec. 31, 2015USD ($)
Restructuring Cost and Reserve [Line Items]
Business restructuring	$ 191,000,000	$ 0	$ 0	$ 0	$ 0	$ 191,000,000	$ 136,000,000
2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net of accrual adjustment						195,000,000
Employee severance costs						136,000,000
Restructuring and related cost, expected number of positions eliminated | employee					1,700
Asset Write-offs						59,000,000
Business restructuring						$ 191,000,000
Employees Impacted					949	1,958
Activity to date					$ (46,000,000)	$ (65,000,000)
Activity to date - employees impacted					(969)	(40)
Foreign currency translation adjustment amount					$ 18,000,000
Total reserve balance at end of year	130,000,000				102,000,000	$ 130,000,000
2015 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, accrual adjustment						4,000,000
Performance Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business restructuring						$ 122,000,000
Employees Impacted | employee						1,069
Industrial Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business restructuring						$ 66,000,000
Employees Impacted | employee						804
Corporate Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business restructuring						$ 7,000,000
Employees Impacted | employee						85
Severance and Other Costs | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance and Other Costs						$ 136,000,000
Activity to date					(46,000,000)	(6,000,000)
Foreign currency translation adjustment amount					18,000,000
Total reserve balance at end of year	130,000,000				102,000,000	130,000,000
Severance and Other Costs | Performance Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance and Other Costs						77,000,000
Severance and Other Costs | Industrial Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance and Other Costs						52,000,000
Severance and Other Costs | Corporate Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Severance and Other Costs						7,000,000
Asset Write Offs Or Other | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Asset Write-offs						59,000,000
Activity to date					0	(59,000,000)
Foreign currency translation adjustment amount					0
Total reserve balance at end of year	0				$ 0	0
Asset Write Offs Or Other | Performance Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Asset Write-offs						45,000,000
Asset Write Offs Or Other | Industrial Coatings Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Asset Write-offs						14,000,000
Asset Write Offs Or Other | Corporate Segment | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Asset Write-offs						0
As Previously Reported
Restructuring Cost and Reserve [Line Items]
Business restructuring	$ 195,000,000					195,000,000
As Previously Reported | 2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net of accrual adjustment						195,000,000
Business restructuring						$ 195,000,000

Borrowings and Lines of Credi65

Borrowings and Lines of Credit (Long-term Debt Obligations) (Details) € in Millions, $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jan. 31, 2016USD ($)	Dec. 31, 2016USD ($)	Mar. 31, 2017USD ($)	Jun. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Long-term debt		$ 4,299				$ 4,123		$ 4,299
Capital lease obligations		18				15		18
Long-term debt and capital lease obligations		4,317				4,138		4,317
Less payments due within one year		530				4		530
Long-term debt		$ 3,787	$ 3,817	$ 3,998	$ 4,089	$ 4,134		$ 3,787
Effective interest rates		8.40%				8.40%		8.40%
Repayments of debt			$ 7	$ 8	$ 9	$ 588		$ 379	$ 340
Proceeds from notes payable		$ 987						1,240
Notional amount of non-derivative instruments | €							€ 300
Notes 6.875 Percent Due 2017
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						6.875%
Notes 3.875 Percent Due 2015
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						3.875%
Notes 1.9 Percent Due 2016
Debt Instrument [Line Items]
Notional amount of non-derivative instruments	$ 250
Debt instrument, interest rate, stated percentage	1.90%					1.90%
3-year Variable Rate Euro Bank Loan Due 2017
Debt Instrument [Line Items]
Long-term debt		526				$ 0		526
Repayments of debt						587
Notional amount of non-derivative instruments | €							500
Notes 0.00% Due 2019
Debt Instrument [Line Items]
Long-term debt		313				$ 358		313
Notional amount of non-derivative instruments | €							300
Debt instrument, interest rate, stated percentage						0.00%
Notes 2.3 Percent Due 2019
Debt Instrument [Line Items]
Long-term debt		298				$ 299		298
Debt instrument, interest rate, stated percentage						2.30%
Notes 3.6 Percent Due 2020
Debt Instrument [Line Items]
Long-term debt		496				$ 497		496
Debt instrument, interest rate, stated percentage						3.60%
Non-callable Debentures 9 Percent Due 2021
Debt Instrument [Line Items]
Long-term debt		133				$ 133		133
Debt instrument, interest rate, stated percentage						9.00%
Notes 0.875 Percent Due 2022
Debt Instrument [Line Items]
Long-term debt		626				$ 716		626
Notional amount of non-derivative instruments | €							600
Debt instrument, interest rate, stated percentage						0.875%
Notes 0.875% Due 2025
Debt Instrument [Line Items]
Long-term debt		621				$ 710		621
Notional amount of non-derivative instruments | €							600
Debt instrument, interest rate, stated percentage						0.875%
Notes 1.4 Percent Due 2027
Debt Instrument [Line Items]
Long-term debt		620				$ 711		620
Debt instrument, interest rate, stated percentage						1.40%
Notes 2.5 Percent Due 2029
Debt Instrument [Line Items]
Long-term debt		83				$ 95		83
Notional amount of non-derivative instruments | €							80
Debt instrument, interest rate, stated percentage						2.50%
Notes 7.70 Percent Due 2038
Debt Instrument [Line Items]
Long-term debt		174				$ 174		174
Debt instrument, interest rate, stated percentage						7.70%
Notes 5.5 Percent Due 2040
Debt Instrument [Line Items]
Long-term debt		247				$ 247		247
Debt instrument, interest rate, stated percentage						5.50%
Notes 3.0 Percent Due 2044
Debt Instrument [Line Items]
Long-term debt		118				$ 137		118
Notional amount of non-derivative instruments | €							€ 120
Debt instrument, interest rate, stated percentage						3.00%
Impact Of Derivatives On Debt
Debt Instrument [Line Items]
Long-term debt		3				$ 3		3
Other Non US Debt
Debt Instrument [Line Items]
Long-term debt		$ 41				$ 43		$ 41
Long-term debt, percentage bearing variable interest, percentage rate		3.80%				3.70%		3.80%
Notes 6.65 Percent Due 2018
Debt Instrument [Line Items]
Long-term debt		$ 125						$ 125
Repayments of debt								$ 133
Debt instrument, interest rate, stated percentage		6.65%				6.65%		6.65%
Term Loan Credit Agreements 2016
Debt Instrument [Line Items]
Repayments of debt								$ 250
Notes 7.4 Percent Due 2019
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						7.40%
Notes 2.70 Percent Due 2022
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						2.70%

Borrowings and Lines of Credi66

Borrowings and Lines of Credit (Long-term Debt Maturities) (Details) $ in Millions	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
Aggregate maturities of long-term debt, in 2018	$ 4
Aggregate maturities of long-term debt, in 2019	659
Aggregate maturities of long-term debt, in 2020	497
Aggregate maturities of long-term debt, in 2021	133
Aggregate maturities of long-term debt, in 2022	718
Aggregate maturities of long-term debt, Thereafter	$ 2,127

Borrowings and Lines of Credi67

Borrowings and Lines of Credit (Short-term Debt Outstanding) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Short-term Debt [Line Items]
Short-term Debt	$ 8	$ 99
Other Short-Term Borrowings
Short-term Debt [Line Items]
Various, weighted average 1.9% and 5.8% as of December 31, 2017 and December 31, 2016, respectively.	$ 8	$ 99
Weighted average interest rate	1.90%	5.80%

Borrowings and Lines of Credi68

Borrowings and Lines of Credit (Minimum Lease) (Details) $ in Millions	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
Minimum lease commitments for operating leases, in 2018	$ 212
Minimum lease commitments for operating leases, in 2019	167
Minimum lease commitments for operating leases, in 2020	138
Minimum lease commitments for operating leases, in 2021	86
Minimum lease commitments for operating leases, in 2022	63
Minimum lease commitments for operating leases, thereafter	$ 174

Borrowings and Lines of Credi69

Borrowings and Lines of Credit (Additional Information) (Details) € in Millions	1 Months Ended		2 Months Ended	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jan. 31, 2016USD ($)	Dec. 31, 2015	Dec. 31, 2016USD ($)	Mar. 31, 2017USD ($)	Jun. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2018	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Mar. 31, 2015USD ($)	Mar. 31, 2015EUR (€)
Debt Instrument [Line Items]
Notional amount of non-derivative instruments | €									€ 300
Term of credit agreement		5 years
Revolving credit facility outstanding								$ 1,800,000,000
Line of credit facility, additional borrowing capacity available to lender conditions								$ 500,000,000
Hypothetical rate on the credit agreement								2.56%
Unused capacity, commitment fee percentage								0.09%	0.09%
Total indebtedness to total capitalization ratio requirement								60.00%
Ratio of indebtedness to net capital								0.41
Repayments of debt				$ 7,000,000	$ 8,000,000	$ 9,000,000		$ 588,000,000		$ 379,000,000	$ 340,000,000
Debt instrument, face amount												$ 1,260,000,000	€ 1,200
Proceeds from notes payable			$ 987,000,000							1,240,000,000
Rental expenses for operating leases								288,000,000		273,000,000	$ 260,000,000
Line of credit, amount outstanding			0					0		0
Outstanding letters of credit and surety bonds			160,000,000					163,000,000		160,000,000
Guarantees outstanding			12,000,000					14,000,000		12,000,000
Commercial paper
Debt Instrument [Line Items]
Line of credit, amount outstanding			0					$ 0		0
Notes 1.9 Percent Due 2016
Debt Instrument [Line Items]
Notional amount of non-derivative instruments	$ 250,000,000
Debt instrument, interest rate, stated percentage	1.90%							1.90%
Notes 3.875 Percent Due 2015
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage								3.875%
Net Investment Hedging
Debt Instrument [Line Items]
Repayments of debt								$ 336,000,000
7-year Fixed Rate Euro Bank Loan Due 2022
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage												0.875%	0.875%
Debt instrument, face amount | €													€ 600
12-year Fixed Rate Euro Bank Loan Due 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage												1.40%	1.40%
Debt instrument, face amount | €													€ 600
Notes 2.3 Percent Due 2019
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage								2.30%
Percentage of debt redemption price								101.00%
3-year Variable Rate Euro Bank Loan Due 2017
Debt Instrument [Line Items]
Notional amount of non-derivative instruments | €									€ 500
Repayments of debt								$ 587,000,000
Notes 2.5 Percent Due 2029
Debt Instrument [Line Items]
Notional amount of non-derivative instruments | €									80
Debt instrument, interest rate, stated percentage								2.50%
Notes 3.0 Percent Due 2044
Debt Instrument [Line Items]
Notional amount of non-derivative instruments | €									€ 120
Debt instrument, interest rate, stated percentage								3.00%
Non-callable Debentures 9 Percent Due 2021
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage								9.00%
Long-term debt, contingent payment of principal or interest								$ 10,000,000
Notes 7.70 Percent Due 2038
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage								7.70%
Minimum
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage								0.08%	0.08%
Periodic payment amount								$ 50,000,000
Maximum
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage								0.225%	0.225%
Guarantee of Indebtedness of Others
Debt Instrument [Line Items]
Carrying value of guarantees			1,000,000					$ 1,000,000		1,000,000
Fair value of guarantees			$ 1,000,000					1,000,000		$ 1,000,000
International Operations
Debt Instrument [Line Items]
Lines of credit, current borrowing capacity								589,000,000
Line of credit, amount outstanding								$ 2,000,000
Scenario, Forecast
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage							0.09%

Financial Instruments, Hedgin70

Financial Instruments, Hedging Activities and Fair Value Measurements (Additional Information) (Detail) € in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Dec. 31, 2016USD ($)	Dec. 31, 2016EUR (€)	Dec. 31, 2015USD ($)	Jun. 30, 2016USD ($)shares
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Forward Contract Indexed to Issuer's Equity, Indexed Shares | shares						2,777,778
Forward Contract Indexed To Issuers Equity Shares Principal Amount			$ 60,000,000
Interest Paid by PPG to Counter Party			10,000,000
Forward Contract Indexed To Issuers Equity Fair Value						$ 258,000,000
Foreign Currency Contracts, Liability, Fair Value Disclosure			2,000,000
Derivative Instruments in Hedges, Net Investment in Foreign Operations, Assets, Fair Value, Net	$ 2,000,000		65,000,000
Notional Amount of Nonderivative Instruments | €		€ 300
Fair Value of Debt Instrument Designated as a Hedge of Net Investment in Foreign Operations	2,700,000,000		2,900,000,000
Derivative, Cash Received on Hedge	3,000,000		0		$ 19,000,000
Foreign Currency Contracts, Liability, Fair Value Disclosure	20,000,000
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	16,000,000		482,000,000
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	3,000,000		13,000,000
Net Investment Hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Nonderivative Instruments | €		€ 2,300		€ 2,800
Designated as Hedging Instrument | Foreign Currency Contracts | Cash Flow Hedging | Settlement Date 15 March 2018
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Derivative Instruments Designated as Net Investment Hedges	$ 560,000,000		$ 560,000,000

Financial Instruments, Hedgin71

Financial Instruments, Hedging Activities and Fair Value Measurements (Fair Value, Cash Flow and Net Investment Hedges) (Detail) € in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Dec. 31, 2016USD ($)	Dec. 31, 2016EUR (€)	Dec. 31, 2015USD ($)
Derivatives, Fair Value [Line Items]
Notional Amount of Nonderivative Instruments | €		€ 300
Fair Value Hedging
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount					$ (46)
Fair Value Hedging | Foreign Currency Contracts | Sales
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount					(2)
Fair Value Hedging | Equity Forward Arrangement | Asbestos Issue
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount					(44)
Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	$ (7)		$ 1		57
Gain (Loss) Recognized Amount	9		(5)		50
Cash Flow Hedging | Foreign Currency Contracts | Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	(7)		1		57
Gain (Loss) Recognized Amount	9		(5)		50
Ineffective portion of expense	7		9		7
Net Investment Hedging
Derivatives, Fair Value [Line Items]
Notional Amount of Nonderivative Instruments | €		€ 2,300		€ 2,800
Gain (Loss) Deferred in OCI	(464)		133		181
Net Investment Hedging | Foreign Currency Contracts | Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	0		(14)		19
Net Investment Hedging | Currency Swap
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	(61)		25		77
Net Investment Hedging | Other Foreign Currency Denominated Debt
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	$ (403)		122		85
Economic Hedging [Member] | Foreign Currency Contracts | Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount			$ 14		$ 18

Financial Instruments, Hedgin72

Financial Instruments, Hedging Activities and Fair Value Measurements (Assets and Liabilities Reported at Fair Value on a Recurring Basis) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Level 1 | Short-term Investments | Marketable Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments reported at fair value on a recurring basis	$ 4	$ 4
Level 1 | Investments | Marketable Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments reported at fair value on a recurring basis	79	78
Level 2 | Other Current Assets | Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis	6	22
Level 2 | Other Current Assets | Cross Currency Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis	2	0
Level 2 | Other Assets | Cross Currency Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis		65
Level 2 | Accounts Payable and Accrued Liabilities | Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities reported at fair value on a recurring basis	$ 23	$ 9

Financial Instruments, Hedgin73

Financial Instruments, Hedging Activities and Fair Value Measurements (Fair Value Additional Information) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Foreign Currency Contract, Asset, Fair Value Disclosure		$ 2
Long-term debt	$ 4,123	4,299
Long-term debt (excluding capital lease obligations), fair values	4,341	4,502
Capital lease obligations	15	18
Short-term Debt	8	99
Noncontrolling Interest in Joint Ventures	$ 44	$ 38

Earnings Per Common Share (Calc

Earnings Per Common Share (Calculations) (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings per common share (attributable to PPG)
Continuing operations	$ 148	$ 393	$ 497	$ 331	$ 87	$ (211)	$ 339	$ 328	$ 828	$ 1,221	$ 1,369	$ 543	$ 1,311
Discontinued operations	3	217	(1)	6	253	27	31	19	5	222	225	330	95
Net income (attributable to PPG)	$ 151	$ 610	$ 496	$ 337	$ 340	$ (184)	$ 370	$ 347	$ 833	$ 1,443	$ 1,594	$ 873	$ 1,406
Weighted average common shares outstanding											256,100,000	265,600,000	271,400,000
Effect of dilutive securities:
Stock options											900,000	800,000	1,000,000
Other stock compensation plans											800,000	1,000,000	1,200,000
Potentially dilutive common shares											1,700,000	1,800,000	2,200,000
Adjusted weighted average common shares outstanding											257,800,000	267,400,000	273,600,000
Earnings per common share (attributable to PPG):
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22	$ 4.75	$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.88	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24	5.61	6.22	3.29	5.18
Earnings per common share - assuming dilution (attributable to PPG)
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19	4.72	5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.87	1.23	0.35
Earnings per common share - assuming dilution (in dollars per share)	$ 0.59	$ 2.36	$ 1.92	$ 1.30	$ 1.29	$ (0.69)	$ 1.37	$ 1.29	$ 3.21	$ 5.58	$ 6.18	$ 3.27	$ 5.14
Outstanding stock options excluded from the computation of diluted earnings per share due to their antidilutive effect											600,000	600,000	600,000

Income Taxes (Additional Inform

Income Taxes (Additional Information) (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended			96 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2025
Income Taxes [Line Items]
Net tax charge for Tax Cuts and Jobs Act													$ 134
One-time tax on unrepatriated foreign earnings													250
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability													125
Benefit from reversal of existing deferred tax liability on repatriated foreign earnings													150
Deferred income taxes				$ 6					$ (40)		$ (53)		38	$ 171	$ 0
Pension settlement charge	$ 38	$ 0	$ 0	22	$ 0	$ 968	$ 0	$ 0	22	$ 0	22	$ 968	60	968	0
Net tax charge related to Asbestos Settlement Funding													151
Income before income taxes of non-US operations													2,005	779	1,745
Taxes paid, net of refunds				$ 90					$ 326		$ 481		648	349	383
Net operating loss carryforwards	694				494								694	494
Tax effected amount of net operating loss carryforward	210				140								210	140
Unrecognized tax benefits that would affect the effective tax rate, if recognized	140												140
Accrued estimated interest and penalties on unrecognized tax benefits	15				9								15	9	8
Deferred Tax Assets, Tax Credit Carryforwards, Other	9				57								9	57
Recognized (income) expense for estimated interest and penalties													4	1	2
U.S.
Income Taxes [Line Items]
Income before income taxes of non-US operations													713	(210)	693
Non United States
Income Taxes [Line Items]
Income before income taxes of non-US operations													1,292	889	$ 1,052
Net Operating Loss, Indefinite Life
Income Taxes [Line Items]
Net operating loss carryforwards	447				376								447	376
Net Operating Loss, Expiring Within 20 Years
Income Taxes [Line Items]
Net operating loss carryforwards	$ 247				$ 118								247	$ 118
Pension Settlement Charges
Income Taxes [Line Items]
Deferred income taxes													22
Pension settlement charge													$ 60
Scenario, Forecast | Minimum
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount																$ 1
Scenario, Forecast | Maximum
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount																$ 3

Income Taxes (Components of Inc

Income Taxes (Components of Income Tax Expense) (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current income tax expense
U.S. federal											$ 179	$ (251)	$ 132
U.S. State and local											49	(12)	20
Non-U.S.											349	306	261
Total current income tax											577	43	413
Deferred income tax expense
U.S. federal											107	173	31
U.S. State and local											(16)	(10)	6
Non-U.S.											(53)	8	(37)
Deferred Income Tax Expense (Benefit)				$ 6					$ (40)	$ (53)	38	171	0
Total	$ 224	$ 124	$ 157	$ 110	$ 40	$ (220)	$ 285	$ 109	$ 267	$ 391	$ 615	$ 214	$ 413

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Statutory U.S. Corporate Federal Income Tax Rate to Effective Income Tax Rate) (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	35.00%	35.00%	35.00%
Changes in rate due to:
U.S. tax cost - Tax Cuts & Jobs Act	11.00%	0.00%	0.00%
U.S./foreign tax differential	(9.30%)	(17.70%)	(8.20%)
U.S. current tax benefit on foreign exchange realization	(4.90%)	(3.00%)	0.00%
U.S. state and local taxes	(2.30%)	(3.70%)	(1.90%)
U.S. tax (benefit) cost on foreign dividends	(1.90%)	0.40%	(1.00%)
U.S. state and local taxes	1.10%	(1.80%)	1.00%
U.S. deferred tax benefit on foreign income	(0.60%)	(3.10%)	(4.10%)
Asbestos charge	0.00%	19.10%	0.00%
Other	2.60%	2.30%	2.90%
Effective income tax rate	30.70%	27.50%	23.70%

Income Taxes (Net Deferred Inco

Income Taxes (Net Deferred Income Tax Assets and Liabilities) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)jurisdiction	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Income Tax Examination [Line Items]
Valuation Allowances and Reserves, Balance	$ 170				$ 119
Number of PPG Subsidiaries	250
Number of taxable jurisdictions | jurisdiction	75
Undistributed Earnings of Foreign Subsidiaries	$ 3,400				5,300
Income Tax, Potential U.S. Tax Cost for Repatriation of Foreign Earnings	30				350
Deferred income tax assets related to
Employee benefits	399				606
Contingent and accrued liabilities	164				263
Operating loss and other carry-forwards	221				197
Inventories	6				14
Property	51				49
Other	135				100
Valuation allowance	(173)				(119)
Total	803				1,110
Deferred income tax liabilities related to
Property	314				349
Intangibles	578				647
Employee benefits	11				4
Derivatives	1				6
Undistributed foreign earnings	24				189
Other	20				146
Total	948				1,341
Deferred income tax (liabilities) assets – net	$ (145)	$ (445)	$ (390)	$ (400)	(231)
Minimum
Income Tax Examination [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2018
Tax Credit Carryforward, Expiration Date	Dec. 31, 2018
Maximum
Income Tax Examination [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2030
Tax Credit Carryforward, Expiration Date	Dec. 31, 2027
Undistributed earnings, permanently reinvested
Income Tax Examination [Line Items]
Undistributed Earnings of Foreign Subsidiaries					$ 3,500

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 3,400	$ 5,300
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	94	82	$ 71
Current year tax positions - additions	37	25	14
Prior year tax positions - additions	26	8	5
Pre-acquisition unrecognized tax benefits	0	0	4
Prior year tax positions - reductions	0	(11)	(3)
Statute of limitations expirations	(8)	(8)	(1)
Settlements	(10)	0	(3)
Foreign currency translation	9	(2)	(5)
Ending balance	$ 148	$ 94	$ 82

Employee Benefit Plans (Additio

Employee Benefit Plans (Additional Information) (Detail) $ in Millions	Oct. 01, 2016USD ($)	Jan. 31, 2018USD ($)	Oct. 31, 2016USD ($)	Aug. 31, 2016USD ($)purchase_agreementinsurance_companyretiree	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2015USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)plan	Dec. 31, 2015USD ($)	Jul. 31, 2016
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension settlement charge					$ 38	$ 0	$ 0	$ 22	$ 0	$ 968	$ 0	$ 0	$ 22	$ 0	$ 22	$ 968			$ 60	$ 968	$ 0
Discount rate used to calculate benefit obligation					3.20%				3.70%										3.20%	3.70%
ABO for all defined benefit pension plans					$ 3,382				$ 3,171										$ 3,382	$ 3,171
Net actuarial loss (gain) arising during the year																			$ 3
Return on plan assets assumption																			5.40%	6.10%	6.10%
Impact on net periodic pension expense																			$ 11
Weighted-average healthcare cost trend rate assumed for next fiscal year					6.10%														6.10%
Assumed ultimate health care cost trend rate					4.50%														4.50%
Assumed year that ultimate health care cost trend rate will be reached																			2,024
Recognized expense for defined contribution pension plans																			$ 57	$ 70	$ 60
Defined contribution plan contribution rates as percentage of employee earnings																			6.00%
Company-matching contribution, percent of match																			100.00%
Compensation expense related to the ESOP																			$ 46	48	44
Deductible dividends on PPG shares held by the ESOP																			14	14	13
Expense (income) of the deferred compensation plan																			19	7	5
Increase (Decrease) in fair value of investments																			18	5	3
Obligations under the deferred compensation plan					$ 121				124										121	124
Investments in marketable securities by the deferred compensation plan					83				82										83	82
Aggregate PBO for the pension plans with PBO in excess of plan assets					2,544				2,406										2,544	2,406
Aggregate fair value of plan assets for the pension plans with PBO in excess of plan assets					1,792				1,609										1,792	1,609
Aggregate ABO for the pension plans with ABO in excess of plan assets					2,434				2,302										2,434	2,302
Fair value of plan assets for the pension plans with ABO in excess of plan assets					1,749				1,575										1,749	1,575
Pittsburgh Glass Works L L C
Pension and Other Postretirement Benefits Disclosure [Line Items]
Liabilities for pension and post-employment benefits earned for service up to the time of sale					369				342										369	342
Costs related to the pension and other postemployment benefit liabilities of the divested business																			$ 2	20	17
Minimum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Company-matching contribution																			2.00%
Maximum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Company-matching contribution																			5.00%
Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans																			$ 87	204
Pension assets transferred																			0	(3)
Plan settlements																			95	2,338
Net actuarial loss (gain) arising during the year																			38
Estimated amounts of accumulated net actuarial loss that will be amortized from AOCI into net periodic benefit cost in 2012					68														68
Impact on net periodic pension expense																			22
Benefits paid																			167	233
Estimated future benefit payments in 2018					147														147
Estimated future benefit payments in 2019					147														147
Estimated future benefit payments in 2020					156														156
Estimated future benefit payments in 2021					161														161
Estimated future benefit payments in 2022					166														166
Estimated aggregate future benefits payments for the five years thereafter					901														901
Postretirement Health Coverage
Pension and Other Postretirement Benefits Disclosure [Line Items]
Increase (decrease) in benefit obligation due to U.S. Plan Merger and Remeasurement				$ (306)
Amortization reduction period				5 years 7 months 6 days
Other Postretirement Benefits
Pension and Other Postretirement Benefits Disclosure [Line Items]
Net actuarial loss (gain) arising during the year																			(35)
Estimated amounts of accumulated net actuarial loss that will be amortized from AOCI into net periodic benefit cost in 2012					17														17
Estimated amounts of accumulated prior service cost that will be amortized from AOCI into net periodic benefit cost in 2012					(60)														(60)
Impact on net periodic pension expense																			26
Benefits paid																			48	53
Estimated future benefit payments in 2018					54														54
Estimated future benefit payments in 2019					54														54
Estimated future benefit payments in 2020					53														53
Estimated future benefit payments in 2021					53														53
Estimated future benefit payments in 2022					52														52
Estimated aggregate future benefits payments for the five years thereafter					$ 231														$ 231
Flat Glass Business
Pension and Other Postretirement Benefits Disclosure [Line Items]
Settlement charge																				11
Flat Glass Business | Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Increase (decrease) in benefit obligation due to settlements																				(100)
Pension assets transferred																				55
European Fiber Glass
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension settlement charge			$ 46
Settlement charge																				46
European Fiber Glass | Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Increase (decrease) in benefit obligation due to settlements	$ (340)
Pension assets transferred																				250
United States, Canada, Netherlands and United Kingdom
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of defined benefit pension plan assets market value					93.00%														93.00%
Scenario, Forecast
Pension and Other Postretirement Benefits Disclosure [Line Items]
Weighted-average healthcare cost trend rate assumed for next fiscal year																		5.80%
Assumed ultimate health care cost trend rate																		4.50%
Scenario, Forecast | Flat Glass Business | Pensions | Minimum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension assets transferred																		$ 5
Scenario, Forecast | Flat Glass Business | Pensions | Maximum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension assets transferred																		$ 10
UNITED STATES
Pension and Other Postretirement Benefits Disclosure [Line Items]
Number of definitive purchase agreements | purchase_agreement				2
Number of insurance companies to service future benefit obligations | insurance_company				2
Number of Company's retirees affected by annuity purchase | retiree				13,200
Increase (decrease) in benefit obligation due to settlements																			$ (1,600)
Noncash Pension Settlement Charge - after tax																			535
Pension settlement charge																			857
Contributions to defined benefit pension plans																			$ 54	134	$ 224
Discount rate used to calculate benefit obligation																					4.50%	3.60%
Increase (decrease) in benefit obligation due to U.S. Plan Merger and Remeasurement																				306
Increase (decrease) in pension expense																				10
Return on plan assets assumption																			7.50%
UNITED STATES | Glass Segment
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans																				12	$ 26
UNITED STATES | Scenario, Forecast
Pension and Other Postretirement Benefits Disclosure [Line Items]
Return on plan assets assumption																		7.40%
Foreign Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Noncash Pension Settlement Charge - after tax																				47
Pension settlement charge																				64
Contributions to defined benefit pension plans																			$ 33	54	$ 39
Increase (decrease) in benefit obligation due to U.S. Plan Merger and Remeasurement																				$ (200)
Estimated future mandatory contributions, low end of range					$ 20														20
Estimated future mandatory contributions, high end of range					$ 30														30
Number of legacy plan windups | plan																				2
After-tax wind-up charges																				$ (34)
Pre-tax gain (loss) due to settlements																	$ (7)			(47)
Foreign Plan | Canada
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans																				7
Defined Benefit Plan, Plan Assets, Contributions by Employer, Windup																				1
Foreign Plan | Glass Segment
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans																				4
Foreign Plan | Scenario, Forecast
Pension and Other Postretirement Benefits Disclosure [Line Items]
Return on plan assets assumption																		5.30%
Retained U.S. Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans																			$ 29	146
Welfare Benefits - U.S. and Canada
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of defined benefit pension plan assets market value					85.00%														85.00%
U.S. Qualified Pension Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Noncash Pension Settlement Charge - after tax																			$ 22
Pension settlement charge																			35
Benefits paid																			87
U.S. Non-qualified Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Noncash Pension Settlement Charge - after tax																			14
Cash payment to retirees - U.S. Non-qualified Pension Plan																			40
Pension settlement charge																			22
Defined Contribution Plan [Member]
Pension and Other Postretirement Benefits Disclosure [Line Items]
Accrued pensions					$ 15				$ 11										$ 15	$ 11
Subsequent Event
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contributions to defined benefit pension plans		$ 25

Employee Benefit Plans (Changes

Employee Benefit Plans (Changes in Projected Benefit Obligations, Plan Assets and Funded Status) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	$ 2,561
End balance	2,883	$ 2,561
Amounts recognized in the Consolidated Balance Sheet:
Accounts payable and accrued liabilities	(78)	(124)
Accrued pensions	(729)	(740)		$ (759)	$ (748)	$ (712)
Other postretirement benefits	(699)	(724)		$ (767)	$ (755)	$ (720)
Pensions
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation, Beginning of year	3,252	5,349
Service cost	33	48	$ 57
Interest cost	98	142	196
Plan amendments	0	0
Actuarial losses (gains) - net	185	538
Benefits paid	(167)	(233)
Foreign currency translation adjustments	165	(141)
Settlements and curtailments	(85)	(2,354)
Defined Benefit Plan, Change in Benefit Obligation Attributable to Glass Segment	(1)	(96)
Other	(18)	(1)
Projected benefit obligation, End of year	3,462	3,252	5,349
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	2,561	4,627
Actual return on plan assets	289	470
Company contributions	87	204
Participant contributions	1	1
Benefits paid	(109)	(205)
Plan transfers	0	(3)
Plan settlements	(95)	(2,338)
Plan expenses and other-net	0	0
Foreign currency translation adjustments	149	(134)
Former glass business changes, net	0	(61)
End balance	2,883	2,561	4,627
Funded Status	(579)	(691)
Amounts recognized in the Consolidated Balance Sheet:
Other assets (long-term)	173	110
Accounts payable and accrued liabilities	(23)	(61)
Accrued pensions	(729)	(740)
Other postretirement benefits	0	0
Liabilities held for sale	0	0
Net liability recognized	(579)	(691)
Other Postretirement Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation, Beginning of year	792	1,084
Service cost	10	15	16
Interest cost	24	31	45
Plan amendments	0	(306)
Actuarial losses (gains) - net	(27)	13
Benefits paid	(48)	(53)
Foreign currency translation adjustments	8	2
Settlements and curtailments	0	0
Defined Benefit Plan, Change in Benefit Obligation Attributable to Glass Segment	(8)	6
Other	2	0
Projected benefit obligation, End of year	753	792	$ 1,084
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Funded Status	(753)	(792)
Amounts recognized in the Consolidated Balance Sheet:
Other assets (long-term)	0	0
Accounts payable and accrued liabilities	(54)	(61)
Accrued pensions	0	0
Other postretirement benefits	(699)	(724)
Liabilities held for sale	0	(7)
Net liability recognized	$ (753)	$ (792)

Employee Benefit Plans (Accumul

Employee Benefit Plans (Accumulated Other Comprehensive Loss Pretax Amounts Not Yet Reflected in Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Pensions
Defined Benefit Plan Disclosure [Line Items]
Accumulated net actuarial losses	$ 835	$ 918
Accumulated prior service cost (credit)	0	1
Total	835	919
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated net actuarial losses	180	226
Accumulated prior service cost (credit)	(239)	(298)
Total	$ (59)	$ (72)

Employee Benefit Plans (Change

Employee Benefit Plans (Change in Accumulated Other Comprehensive Loss (Pretax) Relating to Defined Benefit Pension and Other Postretirement Benefits) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain) arising during the year	$ 3
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain) arising during the year	(35)
New prior service cost (credit)	1
Amortization of actuarial loss	12	$ 19	$ 32
Amortization of prior service (cost) credit	59	31	9
Foreign currency translation adjustments	0
Impact of settlements and curtailments	0
Net change	13
Pensions
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain) arising during the year	38
New prior service cost (credit)	(2)
Amortization of actuarial loss	75	110	119
Amortization of prior service (cost) credit	(1)	$ 1	$ 2
Foreign currency translation adjustments	19
Impact of settlements and curtailments	(63)
Net change	$ (84)

Employee Benefit Plans (Net Per

Employee Benefit Plans (Net Periodic Benefit Costs) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 10	$ 15	$ 16
Interest cost	24	31	45
Amortization of prior service credit	(59)	(31)	(9)
Amortization of actuarial losses	12	19	32
Net periodic benefit cost/(income)	(13)	34	84
Pensions
Defined Benefit Plan Disclosure [Line Items]
Service cost	33	48	57
Interest cost	98	142	196
Expected return on plan assets	141	213	287
Amortization of prior service credit	1	(1)	(2)
Amortization of actuarial losses	75	110	119
Settlements, curtailments, and special termination benefits	60	1,015	8
Net periodic benefit cost/(income)	$ 125	$ 1,101	$ 91

Employee Benefit Plans (Weighte

Employee Benefit Plans (Weighted Average Assumptions Used to Determine Benefit Obligation for Defined Benefit Pension and Other Postretirement Plans) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Return on plan assets assumption	5.40%	6.10%	6.10%
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 11
Discount rate used to calculate benefit obligation	3.20%	3.70%
Rate of compensation increase	1.30%	1.60%
Pensions
Defined Benefit Plan Disclosure [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 22
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 26
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Discount rate used to calculate benefit obligation	3.70%	4.30%

Employee Benefit Plans (Weigh86

Employee Benefit Plans (Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost for Defined Benefit Pension and Other Postretirement Plans) (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate used to calculate benefit obligation	3.20%	3.70%
Discount rate	3.60%	3.60%	3.80%
Expected return on assets	5.40%	6.10%	6.10%
Rate of compensation increase	1.30%	1.60%	2.00%
UNITED STATES
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate used to calculate benefit obligation	3.70%	4.30%

Employee Benefit Plans (Effect

Employee Benefit Plans (Effect of One Percentage Point Increase or Decrease in Health Care Cost Trend Rates) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Retirement Benefits [Abstract]
Increase in the aggregate of service and interest cost components of annual expense	$ 1
Decrease in the aggregate of service and interest cost components of annual expense	1
Increase in the benefit obligation	25
Decrease in the benefit obligation	$ 15

Employee Benefit Plans (Weigh88

Employee Benefit Plans (Weighted Average Target Pension Plan Asset Allocations) (Detail)	Dec. 31, 2017	Dec. 31, 2016
Minimum | Equity Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	15.00%	30.00%
Minimum | Debt Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	30.00%	30.00%
Minimum | Real Estate
Asset Category
Weighted average target pension plan asset allocation, minimum	0.00%	0.00%
Minimum | Other
Asset Category
Weighted average target pension plan asset allocation, minimum	20.00%	0.00%
Maximum | Equity Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	45.00%	65.00%
Maximum | Debt Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	65.00%	65.00%
Maximum | Real Estate
Asset Category
Weighted average target pension plan asset allocation, minimum	10.00%	10.00%
Maximum | Other
Asset Category
Weighted average target pension plan asset allocation, minimum	40.00%	20.00%

Employee Benefit Plans (Fair Va

Employee Benefit Plans (Fair Values of the Company's Pension Plan Assets by Asset Category) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total assets in the fair value hierarchy	$ 2,056	$ 1,177
Common-collective trusts	827	1,384
Fair values of pension plan assets	2,883	2,561
Equity Securities | U.S. | US Large Cap
Fair values of pension plan assets	83	80
Equity Securities | U.S. | US Small Cap
Fair values of pension plan assets	29	0
Equity Securities | U.S. | Treasury Stock
Fair values of pension plan assets	0	53
Equity Securities | Developed Markets | Developed Markets
Fair values of pension plan assets	194	155
Debt Securities | Cash and cash equivalents
Fair values of pension plan assets	11	6
Debt Securities | Corporate | Developed Markets
Fair values of pension plan assets	43	42
Debt Securities | Corporate | UNITED STATES
Fair values of pension plan assets	287	91
Debt Securities | Diversified
Fair values of pension plan assets	124	71
Debt Securities | Government | Developed Markets
Fair values of pension plan assets	101	78
Debt Securities | Government | UNITED STATES
Fair values of pension plan assets	69	0
Debt Securities | Other Debt Securities
Fair values of pension plan assets	432	15
Real Estate And Other
Fair values of pension plan assets	683	586
Level 1
Total assets in the fair value hierarchy	212	133
Fair values of pension plan assets	212	133
Level 1 | Equity Securities | U.S. | US Large Cap
Fair values of pension plan assets	0	0
Level 1 | Equity Securities | U.S. | US Small Cap
Fair values of pension plan assets	29	0
Level 1 | Equity Securities | U.S. | Treasury Stock
Fair values of pension plan assets	0	53
Level 1 | Equity Securities | Developed Markets | Developed Markets
Fair values of pension plan assets	115	80
Level 1 | Debt Securities | Cash and cash equivalents
Fair values of pension plan assets	0	0
Level 1 | Debt Securities | Corporate | Developed Markets
Fair values of pension plan assets	0	0
Level 1 | Debt Securities | Corporate | UNITED STATES
Fair values of pension plan assets	0	0
Level 1 | Debt Securities | Diversified
Fair values of pension plan assets	0	0
Level 1 | Debt Securities | Government | Developed Markets
Fair values of pension plan assets	0	0
Level 1 | Debt Securities | Government | UNITED STATES
Fair values of pension plan assets	68	0
Level 1 | Debt Securities | Other Debt Securities
Fair values of pension plan assets	0	0
Level 1 | Real Estate And Other
Fair values of pension plan assets	0	0
Level 2
Total assets in the fair value hierarchy	842	529
Fair values of pension plan assets	842	529
Level 2 | Equity Securities | U.S. | US Large Cap
Fair values of pension plan assets	83	80
Level 2 | Equity Securities | U.S. | US Small Cap
Fair values of pension plan assets	0	0
Level 2 | Equity Securities | U.S. | Treasury Stock
Fair values of pension plan assets	0	0
Level 2 | Equity Securities | Developed Markets | Developed Markets
Fair values of pension plan assets	79	75
Level 2 | Debt Securities | Cash and cash equivalents
Fair values of pension plan assets	11	6
Level 2 | Debt Securities | Corporate | Developed Markets
Fair values of pension plan assets	43	42
Level 2 | Debt Securities | Corporate | UNITED STATES
Fair values of pension plan assets	201	5
Level 2 | Debt Securities | Diversified
Fair values of pension plan assets	124	71
Level 2 | Debt Securities | Government | Developed Markets
Fair values of pension plan assets	101	78
Level 2 | Debt Securities | Government | UNITED STATES
Fair values of pension plan assets	1	0
Level 2 | Debt Securities | Other Debt Securities
Fair values of pension plan assets	14	0
Level 2 | Real Estate And Other
Fair values of pension plan assets	185	172
Level 3
Total assets in the fair value hierarchy	1,002	515
Fair values of pension plan assets	1,002	515	$ 635
Level 3 | Equity Securities | U.S. | US Large Cap
Fair values of pension plan assets	0	0
Level 3 | Equity Securities | U.S. | US Small Cap
Fair values of pension plan assets	0	0
Level 3 | Equity Securities | U.S. | Treasury Stock
Fair values of pension plan assets	0	0
Level 3 | Equity Securities | Developed Markets | Developed Markets
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Cash and cash equivalents
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Corporate | Developed Markets
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Corporate | UNITED STATES
Fair values of pension plan assets	86	86
Level 3 | Debt Securities | Diversified
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Government | Developed Markets
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Government | UNITED STATES
Fair values of pension plan assets	0	0
Level 3 | Debt Securities | Other Debt Securities
Fair values of pension plan assets	418	15
Level 3 | Real Estate And Other
Fair values of pension plan assets	$ 498	$ 414

Employee Benefit Plans (Chang90

Employee Benefit Plans (Change in Fair Value of Company's Level 3 Pension Assets) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	$ 2,561
End balance	2,883	$ 2,561
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	515	635
Realized gains	59	29
Unrealized losses	5	(16)
Transfers (out)/in	386	(77)
Foreign currency losses	37	(56)
End balance	1,002	515
Level 3 | Real Estate
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	129	209
Realized gains	11	28
Unrealized losses	0	(15)
Transfers (out)/in	(5)	(88)
Foreign currency losses	3	(5)
End balance	138	129
Level 3 | Other Debt Securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	16	21
Realized gains	45	1
Unrealized losses	0	0
Transfers (out)/in	355	(5)
Foreign currency losses	2	(1)
End balance	418	16
Level 3 | Hedge Funds and Other Assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	370	405
Realized gains	3	0
Unrealized losses	5	(1)
Transfers (out)/in	36	16
Foreign currency losses	32	(50)
End balance	$ 446	$ 370

Employee Benefit Plans (Employe

Employee Benefit Plans (Employee Savings Plan) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Company-matching contributions are applied to eligible participant compensation	6.00%
Compensation expense related to the ESOP	$ 46	$ 48	$ 44
Deductible dividends on PPG shares held by the ESOP	$ 14	$ 14	$ 13
Minimum
Company-matching contribution	2.00%
Maximum
Company-matching contribution	5.00%

Commitments and Contingent Li92

Commitments and Contingent Liabilities (Litigation Settlements Disclosure) (Detail) $ in Millions	1 Months Ended	12 Months Ended
	May 14, 2002shares	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2008USD ($)
Forward Contract Indexed To Issuers Equity Fair Value					$ 258
Prepayment of future pre-tax cash payments to the trust					$ 764
Cash Paid for Asbestos Settlement Funding		$ 0	$ 813	$ 0
Change in fair value:
Investment in equity affiliates		(134)	(46)	(94)
Other Reserves		$ 180
Asbestos Issue
Loss Contingency, Pending Claims, Number		625
Change in fair value:
Other Reserves		$ 162
Asbestos Settlement Liability, Current
Beginning balance/Prior year activity			796
Change in fair value:
PPG stock			(34)
Equity forward instrument			0
Accretion of asbestos liability			0
Company Stock To Be Contributed To Asbestos Trust			(308)
Reclassification			1
Ending balance/Activity during year				796
Asbestos Settlement Liability, Long-term
Beginning balance/Prior year activity			252
Change in fair value:
PPG stock			0
Accretion of asbestos liability			6
Reclassification			0
Ending balance/Activity during year				252
Equity Forward (Asset) Liability
Forward Contract Indexed To Issuers Equity Fair Value				(223)
Change in fair value:
PPG stock			0
Equity forward instrument			35
Accretion of asbestos liability			0
Settlement of equity forward instrument with counterparty			(49)
Company Stock To Be Contributed To Asbestos Trust			(308)
Reclassification			1
Pre-tax Charge
Beginning balance/Prior year activity		$ 5	12
Change in fair value:
PPG stock			(34)
Equity forward instrument			35
Accretion of asbestos liability			6
Reclassification			0
Ending balance/Activity during year			5	$ 12
Pittsburgh Corning Corporation
Change in fair value:
Investment in equity affiliates			(15)
Other Current Liabilities
Change in fair value:
Cash Contributed to the PC Trust			(506)
Other Noncurrent Liabilities
Change in fair value:
Cash Contributed to the PC Trust			$ (258)
Pittsburgh Corning Corporation | Asbestos Issue
Agreement to convey assets to the PC asbestos settlement trust (the Trust), shares of PPG common stock | shares	2,777,778
Change in fair value:
Future cash payments to the Trust by PPG's participating historical insurance carriers						$ 1,700
Future PPG cash payments to the Trust, prepayment discount rate	5.50%

Commitments and Contingent Li93

Commitments and Contingent Liabilities (Additional Information) (Detail) $ in Millions	12 Months Ended			60 Months Ended
	Dec. 31, 2017USD ($)Location	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2022USD ($)	Jun. 30, 2009Location
Environmental Matters [Abstract]
Reserves for environmental contingencies	$ 258	$ 285
Reserves for environmental contingencies classified as current liabilities	73	76
Pretax charges for environmental remediation costs	10	94	$ 9
Significant Changes in Reserves	27
Cash outlays related to environmental remediation	44	47	109
Historical low end of range of annual environmental remediation expense over the past 15 years	5
Historical high end of range of annual environmental remediation expense over the past 15 years	$ 35
Remediation Period	10 years
Maximum
Environmental Matters [Abstract]
Unreserved loss contingencies related to environmental matters, high estimate	$ 200
Minimum
Environmental Matters [Abstract]
Unreserved loss contingencies related to environmental matters, high estimate	$ 100
Scenario, Forecast | Maximum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies High Estimate				$ 75
Scenario, Forecast | Minimum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies Low Estimate				$ 25
Soil Treatment Transportation And Disposal Of Excavated Soil
Environmental Matters [Abstract]
Percentage of the total remaining reserve	27.00%
Construction Services
Environmental Matters [Abstract]
Percentage of the total remaining reserve	23.00%
Jersey City Manufacturing Plant
Environmental Matters [Abstract]
Reserves for environmental contingencies	$ 136	163
Pretax charges for environmental remediation costs	4	60	0
Legacy Glass and Chemical Sites
Environmental Matters [Abstract]
Reserves for environmental contingencies	71	70
Other Environmental Contingencies
Environmental Matters [Abstract]
Reserves for environmental contingencies	51	52
Pretax charges for environmental remediation costs	$ 6	$ 34	$ 9
Judicial Consent Order
Environmental Matters [Abstract]
Number Of Sites Involved For Environmental Remediation | Location	19				20
Excavation of Soil
Environmental Matters [Abstract]
Percentage of the total remaining reserve	29.00%

Shareholders' Equity (Summary o

Shareholders' Equity (Summary of Shares Outstanding) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Shareholders' Equity Note [Line Items]
Common Stock, Par or Stated Value Per Share	$ 1.667
Preferred stock without par value (in dollars per share)	$ 10,000,000
Shares of common stock authorized	1,200,000,000
Per share cash dividends paid (in dollars per share)	$ 1.7	$ 1.56	$ 1.41
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	257,330,160	266,876,009	271,964,566
Purchases (in shares)	(7,427,557)	(10,725,869)	(6,992,772)
Issuances (in shares)	1,271,796	1,180,020	1,904,215
Ending balance (in shares)	251,174,399	257,330,160	266,876,009
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	581,146,136	581,146,136	581,146,136
Ending balance (in shares)	581,146,136	581,146,136	581,146,136
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	323,815,976	314,270,127	309,181,570
Purchases (in shares)	(7,427,557)	(10,725,869)	(6,992,772)
Issuances (in shares)	1,271,796	1,180,020	1,904,215
Ending balance (in shares)	329,971,737	323,815,976	314,270,127

Accumulated Other Comprehensi95

Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (2,059)	$ (2,076)	$ (2,356)	$ (2,356)	$ (2,356)	$ (2,356)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						542	$ (299)	$ (630)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax						(295)	(135)	(24)
Net change	(2)	23	287	310	308	316	336	(599)
Ending Balance	$ (2,063)	$ (2,059)	(2,076)	(2,059)	(2,063)	(2,057)	(2,356)
Unrealized Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(1,798)	(1,798)	(1,798)	(1,798)	(1,332)	(628)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax						542	(299)	(630)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax						(311)	(167)	(74)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax
Net change							(466)	(704)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent						231
Ending Balance						(1,567)	(1,798)	(1,332)
Pension and Other Post retirement Benefit Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(571)	(571)	(571)	(571)	(1,379)	(1,492)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						20	29	9
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						58	779	104
Net change						78	808	113
Ending Balance						(493)	(571)	(1,379)
Unrealized Gain (Loss) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			13	13	13	13	9	4
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						(4)	3	41
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						(6)	1	(36)
Net change						(10)	4	5
Ending Balance						3	13	9
Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(2,356)	(2,356)	(2,356)	(2,356)	(2,702)	(2,116)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						52	780	68
Net change			$ 280	$ 297	$ 293	299	346	(586)
Ending Balance						$ (2,057)	$ (2,356)	$ (2,702)

Accumulated Other Comprehensi96

Accumulated Other Comprehensive Loss (Additional Information) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Equity [Abstract]
Tax benefit (cost) related to unrealized currency translation adjustments other than translation of foreign denominated balance sheets	$ 141	$ (34)	$ (84)
Tax benefit (cost) related to the adjustment for pension and other postretirement benefits	(33)	(403)	(51)
Cumulative tax benefit related to the adjustment for pension and other postretirement benefits	243	276
Tax benefit (cost) related to the change in the unrealized gain (loss) on derivatives	$ 5	$ 2	$ (2)

Other Income (Detail)

Other Income (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Net gains on the divestitures of businesses		$ 0	$ 25			$ 0	$ 0		$ 25	$ 0	$ 25	$ 0	$ 25	$ 46	$ 0
Royalty income													11	12	15
Share of net earnings of equity affiliates (See Note 6)													12	8	4
Gain on sale of assets													28	6	4
Income from a legal settlement		0	18			0	0		18	$ 0	18	$ 0	18	0	0
Other													56	55	87
Total	$ 41	$ 16	$ 69	$ 24	$ 47	$ 21	$ 45	$ 14	$ 93		$ 109		$ 150	$ 127	$ 110

Stock-Based Compensation (Addit

Stock-Based Compensation (Additional Information) (Detail) $ / shares in Units, shares in Millions, $ in Millions

3 Months Ended

6 Months Ended

9 Months Ended

12 Months Ended

Jun. 30, 2017USD ($)

Mar. 31, 2017USD ($)

Dec. 31, 2016

Sep. 30, 2016

Jun. 30, 2016USD ($)

Mar. 31, 2016USD ($)

Jun. 30, 2017USD ($)

Jun. 30, 2016USD ($)

Sep. 30, 2017USD ($)

Dec. 31, 2017USD ($)target$ / sharesshares

Dec. 31, 2016USD ($)$ / shares

Dec. 31, 2015USD ($)$ / shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Description and Terms

The options are generally exercisable 36 months after being granted and have a maximum term of 10 years.

Shares available for future grants under the PPG Omnibus Plan | shares

8

Stock-based compensation expense | $

$ 8

$ 9

$ 16

$ 10

$ 17

$ 26

$ 26

$ 35

$ 45

$ 54

Total income tax benefit recognized related to the stock-based compensation | $

$ 2

$ 3

$ 5

$ 4

$ 5

$ 9

$ 12

$ 17

$ 18

Maximum term of the outstanding stock options for the PPG Omnibus Plan and the PPG Stock Plan for certain employees

10 years

Weighted average fair value of options granted (in dollars per share) | $ / shares

$ 21.15

$ 17.94

$ 26.94

Earned payout if the target performance is achieved

150.00%

100.00%

150.00%

Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period

36 months

Employee Stock Option

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Total unrecognized compensation cost that have not yet vested | $

$ 7

Cost not yet recognized, period for recognition

1 year 6 months

Restricted Stock Units (RSUs)

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Total unrecognized compensation cost that have not yet vested | $

$ 14

Cost not yet recognized, period for recognition

1 year 8 months

Award vesting period

3 years

Restricted Stock Units (RSUs) | Minimum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is paid based on performance

0.00%

0.00%

0.00%

Restricted Stock Units (RSUs) | Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is paid based on performance

180.00%

180.00%

180.00%

Restricted Stock Units (RSUs) | Performance Period Twenty Thirteen To Twenty Fifteen

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is assumed to vest for the purposes of expense recognition

100.00%

Number of performance targets met

2

Number of performance targets

4

Restricted Stock Units (RSUs) | Performance Period Twenty Fourteen to Twenty Sixteen

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of performance targets met

1

Number of performance targets

2

Restricted Stock Units (RSUs) | Performance Period Twenty Twelve To Twenty Fourteen

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is assumed to vest for the purposes of expense recognition

150.00%

Number of performance targets met

4

Number of performance targets

6

Contingent Share Grants

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Total unrecognized compensation cost that have not yet vested | $

$ 3

Cost not yet recognized, period for recognition

1 year 8 months

3 years

Award vesting period

3 years

3 years

Earned payout if the target performance is achieved

100.00%

Contingent Share Grants | Minimum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is paid based on performance

0.00%

0.00%

0.00%

Contingent Share Grants | Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of the target award that is paid based on performance

220.00%

220.00%

220.00%

Stock-Based Compensation (Weigh

Stock-Based Compensation (Weighted Average Assumptions Used in Calculating Fair Value of Stock Option) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted average exercise price	$ 101.53	$ 95.29	$ 118.02
Risk free interest rate	2.40%	1.60%	1.90%
Expected life of option in years	6 years 6 months	6 years 6 months	6 years 6 months
Expected dividend yield	1.80%	2.10%	2.70%
Expected volatility	22.00%	22.80%	29.20%

Stock-Based Compensation (Stock

Stock-Based Compensation (Stock Options Outstanding, Exercisable and Activity) (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Number of Shares
Beginning Balance	3,881,566
Granted	642,037
Exercised	(856,900)
Forfeited/Expired	(91,078)
Ending Balance	3,575,625	3,881,566
Vested or expected to vest, at end of period	3,530,023
Exercisable, at end of period	1,677,087
Weighted Average Exercise Price
Beginning Balance (in dollars per share)	$ 75.84
Granted (in dollars per share)	101.53
Exercised (in dollars per share)	61.10
Forfeited/Expired (in dollars per share)	101.36
Ending Balance (in dollars per share)	83.34	$ 75.84
Vested or expected to vest, at end of period (in dollars per share)	83.05
Exercisable, at end of period (in dollars per share)	$ 60.13
Weighted Average Remaining Contractual Life (in years)
Outstanding	6 years 5 months	6 years 6 months
Vested or expected to vest, at end of period	6 years 5 months
Exercisable, at end of period	4 years 5 months
Intrinsic Value (in millions)
Outstanding	$ 120	$ 86
Vested or expected to vest, at end of period	120
Exercisable, at end of period	$ 95

Stock-Based Compensation (St101

Stock-Based Compensation (Stock Option Activity) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total intrinsic value of stock options exercised	$ 40	$ 34	$ 92
Cash received from stock option exercises	52	32	53
Income tax benefit from the exercise of stock options	15	12	31
Total fair value of stock options vested	$ 13	$ 16	$ 13

Stock-Based Compensation (RSU A

Stock-Based Compensation (RSU Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Beginning Balance	721,924
Granted	229,667
Additional shares vested	70,525
Released from restrictions	(349,871)
Forfeited	(56,638)
Ending Balance	615,607
Vested or expected vest, at end of period	595,462
Weighted Average Fair Value
Beginning Balance (in dollars per share)	$ 95.65
Granted (in dollars per share)	102.71
Additional shares vested (in dollars per share)	114.08
Released from restrictions (in dollars per share)	103.09
Forfeited (in dollars per share)	89.16
Ending Balance (in dollars per share)	101.73
Vested or expected to vest, at end of period (in dollars per share)	$ 101.89
Intrinsic Value (in millions)
Outstanding	$ 63	$ 69
Vested or expected to vest, at end of period	$ 60

Quarterly Financial Informat103

Quarterly Financial Information - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Continuing operations	$ (148)	$ (393)	$ (497)	$ (331)	$ (87)	$ 211	$ (339)	$ (328)	$ (828)		$ (1,221)		$ (1,369)	$ (543)	$ (1,311)
Net Income (attributable to PPG) (in dollars per share)	$ 0.59	$ 2.36	$ 1.92	$ 1.30	$ 1.29	$ (0.69)	$ 1.37	$ 1.29	$ 3.21		$ 5.58		$ 6.18	$ 3.27	$ 5.14
Continuing operations (in dollars per share)	$ (0.58)	$ (1.52)	$ (1.92)	$ (1.28)	$ (0.33)	$ 0.79	$ (1.25)	$ (1.22)	$ (3.19)		$ (4.72)		$ (5.31)	$ (2.04)	$ (4.79)
Discontinued operations	$ 3	$ 217	$ (1)	$ 6	$ 253	$ 27	$ 31	$ 19	$ 5		$ 222		$ 225	$ 330	$ 95
Earned payout if the target performance is achieved				150.00%	100.00%	150.00%
Stock-based compensation expense			$ 8	$ 9			$ 16	$ 10	$ 17	$ 26	$ 26		$ 35	$ 45	$ 54
Discontinued operations (in dollars per share)	$ 0.01	$ 0.84	$ 0	$ 0.02	$ 0.96	$ 0.10	$ 0.12	$ 0.07	$ 0.02		$ 0.86		$ 0.87	$ 1.23	$ 0.35
Income before income taxes	$ 377	$ 523	$ 659	$ 446	$ 131	$ (426)	$ 630	$ 444	$ 1,105	$ 1,074	$ 1,628	$ 648	$ 2,005	$ 779	$ 1,745
Environmental remediation charge													0	82	0
Defined benefit pension expense				18					34		52		65	85	$ 88
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Continuing operations	$ (1)	$ (1)	$ 7	$ (3)	$ 4				$ 4		$ 3		$ 2	$ 4
Net Income (attributable to PPG) (in dollars per share)	$ 0.01	$ 0	$ (0.02)	$ 0.01	$ (0.01)				$ (0.01)		$ 0		$ 0.01	$ (0.01)
Continuing operations (in dollars per share)	$ 0	$ 0	$ 0.03	$ (0.01)	$ 0.01				$ 0.02		$ 0.01		$ 0.01	$ 0.01
Discontinued operations	$ 3	$ 0	$ 2	$ 0	$ 0				$ 2		$ 2		$ 5	$ 0
Stock-based compensation expense					$ 6.8
Discontinued operations (in dollars per share)	$ 0.01	$ 0	$ 0.01	$ 0	$ 0				$ 0.01		$ 0.01		$ 0.02	$ 0
Customer refundable fees, revenue recognized			$ 1.4	$ 0.4
Income before income taxes	$ 1	$ 2	(12)	6	$ (7)				$ (6)		$ (4)		$ (3)	$ (7)
Restructuring reserve, accrual adjustment					3.4									3.4
Accrued vacation	2.2	(1.3)	(0.9)						$ (0.9)		$ (1.3)		2.2
Severance costs	2.1	1.4	3.5
Health care expenses		3.5	3.5
Environmental remediation charge				0.5									0.5
Defined benefit pension expense	1	$ 1
Discontinued Operations | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Discontinued operations	2.9		1.5
Income before income taxes	$ (4.7)		$ (2.5)
Share-based Compensation | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income before income taxes				(6.8)	$ (6.8)									$ (6.8)
Other Expense
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Environmental remediation charge				$ 0.5									$ 0.5

Quarterly Financial Informat104

Quarterly Financial Information - Quarterly Financial Information (unaudited) (As Restated) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290	$ 11,066	$ 14,748	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	2,119	2,101	2,082	1,905	1,910	1,978	1,988	1,817	3,987	6,088	8,207	7,693	7,786
Continuing operations	148	393	497	331	87	(211)	339	328	828	1,221	1,369	543	1,311
Discontinued operations	3	217	(1)	6	253	27	31	19	5	222	225	330	95
Net income (loss) attributable to parent	$ 151	$ 610	$ 496	$ 337	$ 340	$ (184)	$ 370	$ 347	$ 833	$ 1,443	$ 1,594	$ 873	$ 1,406
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22	$ 4.75	$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.88	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24	5.61	6.22	3.29	5.18
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19	4.72	5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.87	1.23	0.35
Earnings per common share - assuming dilution (in dollars per share)	$ 0.59	$ 2.36	$ 1.92	$ 1.30	$ 1.29	$ (0.69)	$ 1.37	$ 1.29	$ 3.21	$ 5.58	$ 6.18	$ 3.27	$ 5.14

Quarterly Financial Informat105

Quarterly Financial Information (Unaudited) (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly financial information [Line Items]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290	$ 11,066	$ 14,748	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	2,119	2,101	2,082	1,905	1,910	1,978	1,988	1,817	3,987	6,088	8,207	7,693	7,786
Continuing operations	148	393	497	331	87	(211)	339	328	828	1,221	1,369	543	1,311
Discontinued operations	3	217	(1)	6	253	27	31	19	5	222	225	330	95
Net income (attributable to PPG)	$ 151	$ 610	$ 496	$ 337	$ 340	$ (184)	$ 370	$ 347	$ 833	$ 1,443	$ 1,594	$ 873	$ 1,406
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22	$ 4.75	$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.88	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24	5.61	6.22	3.29	5.18
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19	4.72	5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02	0.86	0.87	1.23	0.35
Earnings per common share - assuming dilution (in dollars per share)	$ 0.59	$ 2.36	$ 1.92	$ 1.30	$ 1.29	$ (0.69)	$ 1.37	$ 1.29	$ 3.21	$ 5.58	$ 6.18	$ 3.27	$ 5.14

Quarterly Financial Informat106

Quarterly Financial Information - Quarterly Condensed Consolidated Balance Sheet (unaudited) - Summary of Restatement (Details) - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax assets, net of valuation allowance	$ 803				$ 1,110
Other	353	$ 350	$ 390	$ 439	320
Total current assets	6,477	7,638	7,141	6,763	6,574
Other assets	677	585	582	587	669
Assets	16,538	17,616	16,973	16,154	15,771
Accounts payable and accrued liabilities	3,781	3,900	3,656	3,517	3,460
Total current liabilities	3,895	4,623	4,444	4,285	4,253
Accrued pensions	729	759	748	712	740
Other liabilities	967	928	910	934	935
Liabilities	10,866	11,611	11,245	10,868	10,856
Retained earnings	17,140	17,101	16,606	16,214	15,980
Total PPG shareholders’ equity	5,557	5,897	5,623	5,192	4,828
Noncontrolling interests	115	108	105	94	87
Stockholders' equity, including portion attributable to noncontrolling interest	5,672	6,005	5,728	5,286	4,915	$ 5,069	$ 5,265
Liabilities and Equity	16,538	17,616	16,973	$ 16,154	15,771
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax assets, net of valuation allowance		421			184
Other			394
Total current assets			7,145
Assets		17,615	16,977		15,769
Accounts payable and accrued liabilities	3,780	3,895	3,653
Total current liabilities	3,894	4,618	4,441
Accrued pensions		758
Other liabilities		928	910
Liabilities	10,865	11,605	11,242
Retained earnings	17,141	17,106	16,613		15,984
Total PPG shareholders’ equity	5,558	5,902	5,630		4,826
Noncontrolling interests	115	108	105		87
Stockholders' equity, including portion attributable to noncontrolling interest	5,673	6,010	5,735		4,913
Liabilities and Equity	16,538	17,615	16,977		15,769
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax assets, net of valuation allowance		1			2
Other			(4)
Total current assets			(4)
Assets		1	(4)		2
Accounts payable and accrued liabilities	1	5	3
Total current liabilities	1	5	3
Accrued pensions		1
Other liabilities		0	0
Liabilities	1	6	3
Retained earnings	(1)	(5)	(7)		(4)
Total PPG shareholders’ equity	(1)	(5)	(7)		2
Noncontrolling interests	0
Stockholders' equity, including portion attributable to noncontrolling interest	(1)	(5)	(7)
Liabilities and Equity	$ 0	$ 1	$ (4)		$ 2

Quarterly Financial Informat107

Quarterly Financial Information - Acquisitions and Divestitures (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Net gains on the divestitures of businesses		0	25			0	0		25	$ 0	25	$ 0	25	46	0
Income tax expense	224	124	157	110	40	(220)	285	109	267		391		615	214	413
Net income (loss) attributable to parent	$ 151	610	496	$ 337	$ 340	(184)	370	$ 347	833		1,443		1,594	873	1,406
Glass Segment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		50	84			285	282		167	543	217	828	217	908	1,089
Income from operations		5	12			38	43		21	71	26	109	30	111	137
Net gains on the divestitures of businesses		343				0					343	0	343	421	0
Income tax expense		131	4			11	12		8	21	139	32	140	202	42
Net income (loss) attributable to parent		$ 217	$ 8			$ 27	$ 31		$ 13	$ 50	$ 230	$ 77	$ 233	$ 330	$ 95

Quarterly Financial Informat108

Quarterly Financial Information - Stock-Based Compensation (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Stock-based compensation expense	$ 9	$ 11	$ 26	$ 37
Total income tax benefit recognized related to the stock-based compensation	$ 4	$ 3	$ 9	$ 12

Quarterly Financial Informat109

Quarterly Financial Information - Shareholders’ Equity (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Stockholders' equity, including portion attributable to noncontrolling interest	$ 5,672	$ 6,005	$ 5,728	$ 5,286	$ 4,915				$ 5,728	$ 6,005	$ 5,672	$ 4,915	$ 5,069	$ 5,265
Net income attributable to the controlling and noncontrolling interests	156	616	501	342	344	$ (179)	$ 376	$ 354	843	1,459	1,615	895	1,427
Other comprehensive loss, net of tax		(2)	23	287					310	308	316	336	(599)
Dividends, Common Stock, Cash				(103)					(205)	(321)	(434)	(414)	(383)
Issuance of treasury stock				34					49	75	83	55	71
Stock Repurchased During Period, Value				(163)					(163)	(413)
Stock-based compensation activity				(21)					(16)	(8)		35	46
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders										(5)	(5)	(4)	(4)
Stockholders' Equity, Other				(5)					(5)	(5)
Parent
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Stockholders' equity, including portion attributable to noncontrolling interest	5,557	5,897	5,623	5,192	4,828				5,623	5,897	5,557	4,828	4,983	5,180
Net income attributable to the controlling and noncontrolling interests				337					833	1,443	1,594	873	1,406
Other comprehensive loss, net of tax				280					297	293	299	346	(586)
Dividends, Common Stock, Cash				(103)					(205)	(321)	(434)	(414)	(383)
Issuance of treasury stock				34					49	75	83	55	71
Stock Repurchased During Period, Value				(163)					(163)	(413)
Stock-based compensation activity				(21)					(16)	(8)		35	46
Stockholders' Equity, Other				0					0	0
Non-controlling Interests
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Stockholders' equity, including portion attributable to noncontrolling interest	115	$ 108	$ 105	94	87				105	108	115	87	86	85
Net income attributable to the controlling and noncontrolling interests				5					10	16	21	22	21
Other comprehensive loss, net of tax				7					13	15	17	(10)	(13)
Dividends, Common Stock, Cash				0					0	0
Issuance of treasury stock				0					0	0
Stock Repurchased During Period, Value				0					0	0
Stock-based compensation activity				0					0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders										(5)	(5)	(4)	(4)
Stockholders' Equity, Other				$ (5)					$ (5)	$ (5)
Common Stock
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Stockholders' equity, including portion attributable to noncontrolling interest	$ 969				$ 969						$ 969	$ 969	$ 969	$ 484

Quarterly Financial Informat110

Quarterly Financial Information - Quarterly Reportable Business Segment Information (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues		$ 3,776	$ 3,804	$ 3,486		$ 3,660	$ 3,782	$ 3,411	$ 7,290	$ 7,193	$ 11,066	$ 10,853
Segment income		589	673	557		617	720	544	1,230	1,264	1,819	1,881	$ 2,293	$ 2,356	$ 2,287
Corporate Expenditure		(45)	(32)	(56)		(43)	(60)	(63)	(88)	(123)	(133)	(166)	(181)	(220)	(225)
Interest expense, net of interest income		(22)	(22)	(21)		(28)	(24)	(24)	(43)	(48)	(65)	(76)	(85)	(99)	(86)
Segment Reporting Information Legacy Items		1	2	(8)		(4)	(10)	(11)	(6)	(21)	(5)	(25)	(2)	(114)	(51)
Asset write-down		0	0			0	(10)		0	(10)	0	(10)	(7)	(23)
Gain from the sale of an equity affiliate		0	0	0			20		25	20	25	20	25	39	0
Pension settlement charge	$ (38)	0	0	(22)	$ 0	(968)	0	0	(22)	0	(22)	(968)	(60)	(968)	0
Net gains on the divestitures of businesses		0	25			0	0		25	0	25	0	25	46	0
Income from a legal settlement		0	18			0	0		18	0	18	0	18	0	0
Transaction-related costs		0	(5)	(4)		0	(6)	(2)	(9)	(8)	(9)	(8)	(9)	(8)	(44)
Income before income taxes	$ 377	523	659	446	$ 131	(426)	630	444	1,105	1,074	1,628	648	2,005	779	1,745
Performance Coatings Segment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues		2,290	2,299	2,017		2,223	2,338	2,039	4,316	4,377	6,606	6,600
Segment income		366	409	284		368	428	279	693	707	1,059	1,075	1,321	1,314	1,302
Industrial Coatings Segment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues		1,486	1,505	1,469		1,437	1,444	1,372	2,974	2,816	4,460	4,253
Segment income		$ 223	$ 264	$ 273		$ 249	$ 292	$ 265	$ 537	$ 557	$ 760	$ 806	$ 972	$ 1,042	$ 985

Quarterly Financial Informat111

Quarterly Financial Information - Quarterly Condensed Consolidated Statement of Income (unaudited) (As Restated) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	2,119	2,101	2,082	1,905	1,910	1,978	1,988	1,817	3,987		6,088		8,207	7,693	7,786
Selling, general and administrative	908	902	872	882	868	893	930	897	1,754		2,656		3,564	3,588	3,584
Business restructuring					191	0	0	0					0	191	136
Gain Loss Related To Asbestos Litigation Settlement					0	0	(2)	(3)					0	(5)	(12)
Depreciation	86	85	81	79	79	82	79	79	160		245		331	319	314
Amortization	34	32	32	31	30	31	30	30	63		95		129	121	132
Research and development, net	116	114	113	110	115	115	115	114	223		337		453	459	466
Interest expense	27	27	26	25	29	34	31	31	51		78		105	125	125
Interest income	(7)	(5)	(4)	(4)	(6)	(6)	(7)	(7)	(8)		(13)		(20)	(26)	(39)
Pension settlement charge	38	0	0	22	0	968	0	0	22	$ 0	22	$ 968	60	968	0
Other charges	25	13	12	14	117	12	29	17	26		39		64	175	90
Other income	(41)	(16)	(69)	(24)	(47)	(21)	(45)	(14)	(93)		(109)		(150)	(127)	(110)
Income (loss) from continuing operations before income taxes, noncontrolling interest	377	523	659	446	131	(426)	630	444	1,105	$ 1,074	1,628	$ 648	2,005	779	1,745
Income from continuing operations	153	399	502	336	91	(206)	345	335	838		1,237		1,390	565	1,332
Income tax expense	224	124	157	110	40	(220)	285	109	267		391		615	214	413
Income from discontinued operations, net of tax	3	217	(1)	6	253	27	31	19	5		222		225	330	95
Net income attributable to the controlling and noncontrolling interests	156	616	501	342	344	(179)	376	354	843		1,459		1,615	895	1,427
Less: net income attributable to noncontrolling interests	(5)	(6)	(5)	(5)	(4)	(5)	(6)	(7)	(10)		(16)		(21)	(22)	(21)
Net income (loss) attributable to parent	151	610	496	337	340	(184)	370	347	833		1,443		1,594	873	1,406
Continuing operations	148	393	497	331	87	(211)	339	328	828		1,221		1,369	543	1,311
Discontinued operations	$ 3	$ 217	$ (1)	$ 6	$ 253	$ 27	$ 31	$ 19	$ 5		$ 222		$ 225	$ 330	$ 95
Continuing operations (in dollars per share)	$ 0.59	$ 1.53	$ 1.93	$ 1.29	$ 0.34	$ (0.79)	$ 1.26	$ 1.23	$ 3.22		$ 4.75		$ 5.34	$ 2.05	$ 4.83
Discontinued operations (in dollars per share)	0.01	0.85	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.88	1.24	0.35
Net income (attributable to PPG)	0.60	2.38	1.93	1.31	1.30	(0.69)	1.38	1.30	3.24		5.61		6.22	3.29	5.18
Continuing operations (in dollars per share)	0.58	1.52	1.92	1.28	0.33	(0.79)	1.25	1.22	3.19		4.72		5.31	2.04	4.79
Discontinued operations (in dollars per share)	0.01	0.84	0	0.02	0.96	0.10	0.12	0.07	0.02		0.86		0.87	1.23	0.35
Earnings per common share - assuming dilution (in dollars per share)	0.59	2.36	1.92	1.30	1.29	(0.69)	1.37	1.29	3.21		5.58		$ 6.18	$ 3.27	$ 5.14
Common stock, dividends, per share, declared	$ 0.45	$ 0.45	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.36	$ 0.80		$ 1.25
As Previously Reported
Net sales			$ 3,806	$ 3,486					$ 7,292		$ 11,068		$ 14,750
Cost of sales, exclusive of depreciation and amortization	$ 2,117	$ 2,100									6,087		8,204
Selling, general and administrative	912	905	865	888	$ 861				1,753		2,658		3,570	$ 3,581
Business restructuring					195									195
Other charges				14					26		39		64
Other income	(42)		(72)		(51)				(96)		(112)		(154)	(131)
Income (loss) from continuing operations before income taxes, noncontrolling interest	376	521	671	440	138				1,111		1,632		2,008	786
Income from continuing operations	152	398	509	333	95				842		1,240		1,392	569
Income tax expense	224	123	162	107	43				269		392		616	217
Income from discontinued operations, net of tax	0	217	(3)	6	253				3		220		220	330
Net income attributable to the controlling and noncontrolling interests	152	615	506	339	348				845		1,460		1,612	899
Less: net income attributable to noncontrolling interests	5	6	5	5	4				10		16		(21)	(22)
Net income (loss) attributable to parent	147	609	501	334	344				835		1,444		1,591	877
Continuing operations	147	392	504	328	91				832		1,224		1,371	547
Discontinued operations	$ 0	$ 217	$ (3)	$ 6	$ 253				$ 3		$ 220		$ 220	$ 330
Continuing operations (in dollars per share)	$ 0.58	$ 1.53	$ 1.96	$ 1.28	$ 0.35				$ 3.23		$ 4.76		$ 5.35	$ 2.06
Discontinued operations (in dollars per share)	0	0.85	(0.01)	0.02	0.96				0.01		0.86		0.86	1.24
Net income (attributable to PPG)	0.58	2.38	1.95	1.30	1.31				3.24		5.62		6.21	3.30
Continuing operations (in dollars per share)	0.58	1.52	1.95	1.27	0.34				3.21		4.73		5.32	2.05
Discontinued operations (in dollars per share)	0	0.84	(0.01)	0.02	0.96				0.01		0.85		0.85	1.23
Earnings per common share - assuming dilution (in dollars per share)	0.58	2.36	1.94	1.29	1.30				3.22		5.58		$ 6.17	$ 3.28
Common stock, dividends, per share, declared	$ 0.45	$ 0.45	$ 0.40	$ 0.40	$ 0.40				$ 0.80		$ 1.25
Restatement Adjustment
Net sales			$ (2)	$ 0					$ (2)		$ (2)		$ (2)
Cost of sales, exclusive of depreciation and amortization	$ 2	$ 1									1		3
Selling, general and administrative	(4)	(3)	7	(6)	$ 7				1		(2)		(6)	$ 7
Business restructuring					(4)									(4)
Other charges				0					0		0		0
Other income	1		3		4				3		3		4	4
Income (loss) from continuing operations before income taxes, noncontrolling interest	1	2	(12)	6	(7)				(6)		(4)		(3)	(7)
Income from continuing operations	1	1	(7)	3	(4)				(4)		(3)		(2)	(4)
Income tax expense	0	1	(5)	3	(3)				(2)		(1)		(1)	(3)
Income from discontinued operations, net of tax	3	0	2	0	0				2		2		5	0
Net income attributable to the controlling and noncontrolling interests	4	1	(5)	3	(4)				(2)		(1)		3	(4)
Less: net income attributable to noncontrolling interests	0	0	0	0	0				0		0		0	0
Net income (loss) attributable to parent	4	1	(5)	3	(4)				(2)		(1)		3	(4)
Continuing operations	1	1	(7)	3	(4)				(4)		(3)		(2)	(4)
Discontinued operations	$ 3	$ 0	$ 2	$ 0	$ 0				$ 2		$ 2		$ 5	$ 0
Continuing operations (in dollars per share)	$ 0.01	$ 0	$ (0.03)	$ 0.01	$ (0.01)				$ (0.01)		$ (0.01)		$ (0.01)	$ (0.01)
Discontinued operations (in dollars per share)	0.01	0	0.01	0	0				0.01		0		0.02	0
Net income (attributable to PPG)	0.02	0	(0.02)	0.01	(0.01)				0		(0.01)		0.01	(0.01)
Continuing operations (in dollars per share)	0	0	(0.03)	0.01	(0.01)				(0.02)		(0.01)		(0.01)	(0.01)
Discontinued operations (in dollars per share)	0.01	0	0.01	0	0				0.01		0.01		0.02	0
Earnings per common share - assuming dilution (in dollars per share)	0.01	0	(0.02)	0.01	(0.01)				(0.01)		0		$ 0.01	$ (0.01)
Common stock, dividends, per share, declared	$ 0	$ 0	$ 0	$ 0	$ 0				$ 0		$ 0

Quarterly Financial Informat112

Quarterly Financial Information - Quarterly Condensed Consolidated Statement of Comprehensive Income (unaudited) (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Other Comprehensive Income [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 156	$ 616	$ 501	$ 342	$ 344	$ (179)	$ 376	$ 354	$ 843	$ 1,459	$ 1,615	$ 895	$ 1,427
Unrealized foreign currency translation gains/(losses)		(29)	(55)	21					(34)	(63)	248	(476)	(717)
Defined benefit pension and other postretirement benefit adjustments		26	82	279					361	387	78	808	113
Unrealized (losses)/gains – derivative financial instruments		1	(4)	(13)					(17)	(16)	(10)	4	5
Other comprehensive loss, net of tax		(2)	23	287					310	308	316	336	(599)
Total comprehensive income		614	524	629					1,153	1,767	1,931	1,231	828
Less: net income attributable to noncontrolling interests	$ 5	6	5	5	$ 4	$ 5	$ 6	$ 7	10	16	21	22	21
Unrealized foreign currency translation (losses)/gains		(2)	(6)	(7)					(13)	(15)	(17)	10	13
Comprehensive income attributable to PPG		$ 606	$ 513	$ 617					$ 1,130	$ 1,736	$ 1,893	$ 1,219	$ 820

Quarterly Financial Informat113

Quarterly Financial Information - Quarterly Condensed Consolidated Balance Sheets (unaudited) (As Restated) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash and cash equivalents	$ 1,436	$ 2,287	$ 1,569	$ 1,349	$ 1,820	$ 1,311	$ 686
Short-term investments	55	41	48	40	43
Receivables	2,903	3,155	3,191	3,013	2,654
Inventories	1,730	1,805	1,766	1,699	1,514
Assets held for sale	0	0	177	223	223
Other	353	350	390	439	320
Total current assets	6,477	7,638	7,141	6,763	6,574
Property, plant and equipment, net	2,824	2,730	2,710	2,659	2,608	2,608
Goodwill	3,942	3,881	3,845	3,720	3,572	3,625
Identifiable intangible assets, net	2,045	2,099	2,118	2,080	1,983
Deferred income taxes	305	422	321	170	186
Investments	268	261	256	175	179
Other assets	677	585	582	587	669
Assets	16,538	17,616	16,973	16,154	15,771
Accounts payable and accrued liabilities	3,781	3,900	3,656	3,517	3,460
Restructuring reserves	102	107	115	95	100
Short-term debt and current portion of long-term debt	12	616	619	604	629
Liabilities held for sale	0	0	54	69	64
Total current liabilities	3,895	4,623	4,444	4,285	4,253
Long-term debt	4,134	4,089	3,998	3,817	3,787
Accrued pensions	729	759	748	712	740
Other postretirement benefits	699	767	755	720	724
Deferred income taxes	145	445	390	400	231
Deferred income taxes	442				417
Deferred Tax Liabilities, Gross	948				1,341
Other liabilities	967	928	910	934	935
Liabilities	10,866	11,611	11,245	10,868	10,856
Commitments and contingent liabilities (See Note 14)
Common stock	969	969	969	969	969
Additional paid-in capital	756	745	723	711	707
Retained earnings	17,140	17,101	16,606	16,214	15,980
Treasury stock, value	(11,251)	(10,855)	(10,616)	(10,626)	(10,472)
Accumulated other comprehensive loss	(2,057)	(2,063)	(2,059)	(2,076)	(2,356)
Total PPG shareholders’ equity	5,557	5,897	5,623	5,192	4,828
Noncontrolling interests	115	108	105	94	87
Stockholders' equity, including portion attributable to noncontrolling interest	5,672	6,005	5,728	5,286	4,915	$ 5,069	$ 5,265
Liabilities and Equity	16,538	17,616	16,973	$ 16,154	15,771
Restatement Adjustment
Other			(4)
Total current assets			(4)
Assets		1	(4)		2
Accounts payable and accrued liabilities	1	5	3
Total current liabilities	1	5	3
Accrued pensions		1
Other liabilities		0	0
Liabilities	1	6	3
Additional paid-in capital					6
Retained earnings	(1)	(5)	(7)		(4)
Total PPG shareholders’ equity	(1)	(5)	(7)		2
Noncontrolling interests	0
Stockholders' equity, including portion attributable to noncontrolling interest	(1)	(5)	(7)
Liabilities and Equity	0	1	(4)		2
As Previously Reported
Other			394
Total current assets			7,145
Assets		17,615	16,977		15,769
Accounts payable and accrued liabilities	3,780	3,895	3,653
Total current liabilities	3,894	4,618	4,441
Accrued pensions		758
Other liabilities		928	910
Liabilities	10,865	11,605	11,242
Additional paid-in capital					701
Retained earnings	17,141	17,106	16,613		15,984
Total PPG shareholders’ equity	5,558	5,902	5,630		4,826
Noncontrolling interests	115	108	105		87
Stockholders' equity, including portion attributable to noncontrolling interest	5,673	6,010	5,735		4,913
Liabilities and Equity	$ 16,538	$ 17,615	$ 16,977		$ 15,769

Quarterly Financial Informat114

Quarterly Financial Information - Quarterly Condensed Consolidated Statement of Cash Flows (unaudited) (As Restated) (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Cash Flows [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 156	$ 616	$ 501	$ 342	$ 344	$ (179)	$ 376	$ 354	$ 843		$ 1,459		$ 1,615	$ 895	$ 1,427
Income from discontinued operations, net of tax	3	217	(1)	6	253	27	31	19	5		222		225	330	95
Income from continuing operations	153	399	502	336	91	(206)	345	335	838		1,237		1,390	565	1,332
Depreciation and amortization				110					223		340		460	440	446
Defined benefit pension expense				18					34		52		65	85	88
Pension settlement charges	38	0	0	22	0	$ 968	0	0	22	$ 0	22	$ 968	60	968	0
Stock-based compensation expense			8	9			16	$ 10	17	26	26		35	45	54
Net gain, from sale of businesses		0	0	0			$ (20)		(25)	$ (20)	(25)	$ (20)	(25)	(39)	0
Equity affiliate (income)/loss, net of dividends				(1)					3		0		(4)	(6)	66
Deferred income taxes				6					(40)		(53)		38	171	0
Cash contributions to pension plans				(34)					(37)		(43)		(87)	(188)	(263)
Restructuring cash expenditures				(10)					(20)		(31)		(49)	(76)	(47)
Receivables				(296)					(406)		(350)		(76)	(68)	(125)
Inventories				(157)					(185)		(200)		(116)	56	37
Other current assets				(47)					(49)		(40)		(43)	21	(81)
Accounts payable and accrued liabilities				62					147		229		188	169	152
Noncurrent assets and liabilities, net				39					(14)		(102)		(170)	(53)	79
Taxes and interest payable				(82)					(128)		(115)		(129)	(268)	(96)
Other				24					52		71		14	(64)	(19)
Cash from operating activities - continuing operations				(1)					432		1,018		1,551	1,218	1,759
Cash from operating activities - discontinued operations				10					14		14		17	133	136
Cash from operating activities				9					446		1,032		1,568	1,351	1,895
Additions to property and investments				(63)					(135)		(207)		(360)	(380)	(430)
Business acquisitions, net of cash balances acquired (See Note 2)				(61)					(62)		(69)		(225)	(349)	(320)
Payments for acquisition of equity investment				0					(100)		(100)		(100)	0	0
Net proceeds from the sale of businesses				0					52		593		593	1,094	47
Proceeds from maturity of short-term investments													0	92	402
Purchase of short-term investments				0					0		0		(1)	0	(97)
Payments for the settlement of cross currency swap contracts				(34)					(34)		(34)		(34)	(36)	(34)
Proceeds from the settlement of cross currency swap contracts				19					19		37		37	37	37
(Payments on) / Proceeds from net investment hedges													0	(13)	19
Other				2					2		0		27	27	27
Cash (used for)/from investing activities - continuing operations				(137)					(258)		220		(63)	472	(349)
Cash used for investing activities - discontinued operations				(1)					(3)		(4)		(4)	(36)	(46)
Cash (used for)/from investing activities				(138)					(261)		216		(67)	436	(395)
Net change in borrowings with maturities of three months or less				(7)					(3)		(6)		(7)	(15)	(32)
Net payments on commercial paper and short-term debt				(32)					(61)		(81)		(93)	(361)	(528)
Proceeds from long term debt (net of discount and issuance costs) (See Note 8)													0	988	1,242
Repayments of debt				(7)					(8)		(9)		(588)	(379)	(340)
Payments related to tax withholding on stock-based compensation awards				(16)					(20)		(25)		(28)	(26)	(58)
Purchase of treasury stock				(163)					(163)		(413)		(813)	(1,050)	(751)
Issuance of treasury stock				9					20		45		52	31	53
Dividends paid on PPG common stock				(103)					(205)		(321)		(434)	(414)	(383)
Other				(53)					(50)		(41)		(43)	16	(15)
Cash used for financing activities				(372)					(490)		(851)		(1,954)	(1,210)	(812)
Effect of currency exchange rate changes on cash and cash equivalents				30					54		70		69	(68)	(63)
Net (decrease) increase in cash and cash equivalents				(471)					(251)		467		(384)	509	625
Cash and cash equivalents	$ 1,436	$ 2,287	$ 1,569	1,349	$ 1,820				1,569		2,287		1,436	1,820	1,311	$ 686
Interest paid, net of amount capitalized				23					52		60		100	118	115
Taxes paid, net of refunds				$ 90					$ 326		$ 481		$ 648	$ 349	$ 383

Reportable Business Segment 115

Reportable Business Segment Information (Reportable Segment Information) (Detail) - Segment	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Number of PPG operating segments		10
Number of PPG reportable business segments, based on economic similarities, the nature of their products, production processes, end-use markets and methods of distribution		2
Scenario, Forecast
Segment Reporting Information [Line Items]
Number of PPG operating segments	9

Reportable Business Segment 116

Reportable Business Segment Information Reportable Segment Tables (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Segment income			589	673	557		617	720	544	1,230	$ 1,264	1,819	$ 1,881	2,293	2,356	2,287
Legacy items			1	2	(8)		(4)	(10)	(11)	(6)	(21)	(5)	(25)	(2)	(114)	(51)
Restructuring Charges						(191)	0	0	0					0	(191)	(136)
Charges related to transaction related costs			0	(5)	(4)		0	(6)	(2)	(9)	(8)	(9)	(8)	(9)	(8)	(44)
Pension settlement charge		38	0	0	22	0	968	0	0	22	0	22	968	60	968	0
Asset write-down			0	0			0	(10)		0	(10)	0	(10)	(7)	(23)
Income from a legal settlement			0	18			0	0		18	0	18	0	18	0	0
Net gains on the divestitures of businesses			0	25			0	0		25	0	25	0	25	46	0
Interest expense, net of interest income			(22)	(22)	(21)		(28)	(24)	(24)	(43)	(48)	(65)	(76)	(85)	(99)	(86)
Corporate unallocated			(45)	(32)	(56)		(43)	(60)	(63)	(88)	(123)	(133)	(166)	(181)	(220)	(225)
Income before income taxes														2,005	779	1,745
Depreciation and amortization					110					223		340		460	440	446
Share of net earnings (loss) of equity affiliates														12	8	4
Assets	$ 16,973	16,538	17,616	16,973	16,154	15,771				16,973		17,616		16,538	15,771
Investment in equity affiliates		134				46								134	46	94
Expenditures for property (including business acquisitions)														685	729	750
Pretax charges for environmental remediation costs														10	94	9
Performance Coatings Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														8,730	8,580	8,765
Segment income			366	409	284		368	428	279	693	707	1,059	1,075	1,321	1,314	1,302
Depreciation and amortization														272	272	296
Share of net earnings (loss) of equity affiliates														2	5	7
Investment in equity affiliates		32				30								32	30	45
Expenditures for property (including business acquisitions)														224	187	298
Industrial Coatings Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														6,018	5,691	5,477
Segment income			$ 223	$ 264	$ 273		$ 249	$ 292	$ 265	$ 537	$ 557	$ 760	$ 806	972	1,042	985
Depreciation and amortization														164	143	124
Share of net earnings (loss) of equity affiliates														0	1	0
Investment in equity affiliates		13				13								13	13	13
Expenditures for property (including business acquisitions)														328	510	414
Consolidation, Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														0	(1)	(1)
Depreciation and amortization														24	25	26
Share of net earnings (loss) of equity affiliates														10	2	(3)
Investment in equity affiliates		89				3								89	3	36
Expenditures for property (including business acquisitions)														133	32	38
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														14,748	14,270	14,241
Assets		16,538				15,771								16,538	15,771	17,076
Operating Segments | Performance Coatings Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														8,730	8,580	8,765
Assets		9,763				9,168								9,763	9,168	9,917
Operating Segments | Industrial Coatings Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														6,018	5,690	5,476
Assets		4,563				3,972								4,563	3,972	3,643
Operating Segments | Consolidation, Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets		$ 2,212				$ 2,631								2,212	2,631	3,516
Intersegment Eliminations | Industrial Coatings Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														0	1	1
Intersegment Eliminations | Consolidation, Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales														0	(1)	$ (1)
Mexican Plaka Business
Segment Reporting, Revenue Reconciling Item [Line Items]
Net gains on the divestitures of businesses	$ 25													25
Other Business Affiliates
Segment Reporting, Revenue Reconciling Item [Line Items]
Gain (Loss) on Disposition of Assets														$ 13
Legacy Chemical Sites
Segment Reporting, Revenue Reconciling Item [Line Items]
Pretax charges for environmental remediation costs															$ 82

Reportable Business Segment 117

Reportable Business Segment Information (Geographic Information) (Detail) - USD ($) $ in Millions	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 3,417	$ 3,660	$ 3,782	$ 3,411	$ 7,290		$ 11,066		$ 14,748	$ 14,270	$ 14,241
Segment income		589	673	557		$ 617	$ 720	$ 544	1,230	$ 1,264	1,819	$ 1,881	2,293	2,356	2,287
Property, plant and equipment, net	2,824	$ 2,730	$ 2,710	$ 2,659	2,608				$ 2,710		$ 2,730		2,824	2,608	2,608
United States and Canada
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales													6,307	6,254	6,232
Segment income													1,129	1,152	1,176
Property, plant and equipment, net	1,224				1,184								1,224	1,184	1,101
Latin America
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales													1,529	1,421	1,473
Segment income													234	232	213
Property, plant and equipment, net	281				251								281	251	271
Europe, Middle East and Africa (“EMEA”)
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales													4,389	4,164	4,103
Segment income													569	590	539
Property, plant and equipment, net	826				726								826	726	805
Asia Pacific
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales													2,523	2,431	2,433
Segment income													361	382	359
Property, plant and equipment, net	$ 493				$ 447								$ 493	$ 447	$ 431

Schedule II - Valuation and 118

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 119
Balance at End of Year	170	$ 119
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	36	43	$ 80
Charged to Costs and Expenses	15	22	10
Deductions	(26)	(29)	(47)
Balance at End of Year	$ 25	$ 36	$ 43