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- Definition

Number of Stock Option Plans

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- Definition

Performance Share Payout

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- Definition

Performance Share Payout, Description

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Target Award

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- Definition

Share Based Compensation Arrangement by Share based Payment Award, Vesting Percentage

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- Definition

Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11283-113907

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Subparagraph (d)(1)
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- Definition

Description of significant modifications (such as a change in expiration dating, vesting rights, or exercise prices) to an equity-based compensation plan, including the terms of the modifications.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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- Definition

Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
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Stock-Based Compensation (Additional Information) (Detail) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) OptionPlan $ / shares shares	Dec. 31, 2014 USD ($) $ / shares	Dec. 31, 2013 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of options granted (in dollars per share) \| $ / shares	$ 26.94	$ 21.55	$ 13.68
Shares available for future grants under the PPG Omnibus Plan \| shares	10.0
Stock-based compensation expense	$ 56	$ 73	$ 81
Total income tax benefit recognized related to the stock-based compensation	$ 19	$ 25	$ 28
Number of stock option plans \| OptionPlan	2
Maximum term of the outstanding stock options for the PPG Omnibus Plan and the PPG Stock Plan for certain employees	10 years
Description of the terms of the outstanding stock options for the PPG Omnibus Plan and the PPG Stock Plan for certain employees	The options are generally exercisable 36 months after being granted and have a maximum term of 10 years.
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]
Cost not yet recognized, period for recognition	1 year 5 months
Total unrecognized compensation cost that have not yet vested	$ 8
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cost not yet recognized, period for recognition	1 year 8 months 12 days
Award vesting period	3 years
Total unrecognized compensation cost that have not yet vested	$ 17
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 [Member] [Domain]
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	4
Restricted Stock Units (RSUs) \| Performance Period Twenty Thirteen To Twenty Fifteen [Member] [Domain] \| Performance Targets Met
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance targets	4
Restricted Stock Units (RSUs) \| Performance Period Twenty Fourteen to Twenty Sixteen [Domain]
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	2
Restricted Stock Units (RSUs) \| Performance Period Twenty Fourteen to Twenty Sixteen [Domain] \| Performance Targets Met
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance targets	2
Restricted Stock Units (RSUs) \| Performance Period Twenty Twelve To Twenty Fourteen [Member]
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	180.00%
Number of performance targets	6
Restricted Stock Units (RSUs) \| Performance Period Twenty Twelve To Twenty Fourteen [Member] \| Performance Targets Met
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance targets	6
Contingent Share Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cost not yet recognized, period for recognition	1 year 7 months		3 years
Award vesting period	3 years	3 years
Earned payout if the target performance is achieved	100.00%
Total unrecognized compensation cost that have not yet vested	$ 4
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%
Contingent Share Grants \| Performance Period 2011 To 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share payout description		Dividend equivalents for the award period, which will be paid to participants with the award payout at the end of the period based on the actual number of contingent shares that are earned.
Contingent Share Grants \| 2010-2013 Performance Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share payout description			Dividend equivalents for the award period, which will be paid to participants with the award payout at the end of the period based on the actual number of contingent shares that are earned.
Contingent Share Grants \| Performance Period Twenty Twelve To Twenty Fourteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share payout description	Dividend equivalents for the award period, which will be paid to participants with the award payout at the end of the period based on the actual number of contingent shares that are earned.