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

+ References

No definition available.

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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
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-SubTopic 20
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-Paragraph 20
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Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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.

+ References

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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No definition available.

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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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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
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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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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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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, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) target $ / shares shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($) $ / 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										8.0
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%