Employee Benefit Plans (Additional Information) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension and Other Postretirement Benefits Disclosure [Line Items]
ABO for all defined benefit pension plans			$ 5,220.0	$ 5,624.0
Aggregate PBO for the pension plans with PBO in excess of plan assets			4,717.0	4,864.0
Aggregate fair value of plan assets for the pension plans with PBO in excess of plan assets			3,937.0	3,879.0
Aggregate ABO for the pension plans with ABO in excess of plan assets			4,351.0	4,453.0
Fair value of plan assets for the pension plans with ABO in excess of plan assets			$ 3,676.0	$ 3,584.0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets		7.25%	6.10%	6.50%	6.50%
Weighted-average healthcare cost trend rate assumed for next fiscal year		6.30%	6.40%
Assumed ultimate health care cost trend rate		4.50%	4.50%
Assumed year that ultimate health care cost trend rate will be reached			2024
Estimated future benefit payments in 2016			$ 66.0
Estimated future benefit payments in 2017			66.0
Estimated future benefit payments in 2018			67.0
Estimated future benefit payments in 2019			67.0
Benefits paid				$ 61.0
Accrued pensions			$ 712.0	995.0
Defined Contribution Plan Contribution Rates As Percentage Of Employees Earnings			6.00%		6.00%
Expense (income) of the deferred compensation plan			$ 5.0	10.0	$ 18.0
Deferred Compensation Arrangement With Individual Increase Decrease In Fair Value Of Investments			3.0	8.0	17.0
Realized gains on the investment portfolio of the deferred compensation plan			3.0	3.0	$ 3.0
Obligations under the deferred compensation plan			124.0	119.0
Investments in marketable securities by the deferred compensation plan			$ 81.0	79.0
Defined Contribution Plan Contribution Rate			100.00%		75.00%
Deductible dividends on PPG shares held by the ESOP			$ 13.0	14.0	$ 15.0
Minimum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Contribution Plan Contribution Rate		2.00%
Maximum
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Contribution Plan Contribution Rate		5.00%			100.00%
Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Recognized expense for defined contribution pension plans			60.0	55.0	$ 49.0
Accrued pensions			12.0	14.0
Pittsburgh Glass Works LLC
Pension and Other Postretirement Benefits Disclosure [Line Items]
Costs related to the pension and other postemployment benefit liabilities of the divested business			17.0	19.0	30.0
Liabilities for pension and post-employment benefits earned for service up to the time of sale			867.0	945.0
Owen Sound Facility [Member]
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension Settlement Charge, Canadian wind-up			7.0	2.0
Plant closures in Canada, partial wind-ups of the pension plans, settlement charge, low estimate			40.0
Plant closures in Canada, partial wind-ups of the pension plans, settlement charge, high estimate			50.0
Plant closures in Canada, pension plan deficit, low estimate			5.0
Plant closures in Canada, pension plan deficit, high estimate			$ 10.0
Welfare Benefits - U.S. and Canada [Member]
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of defined benefit pension plan assets market value			91.00%
Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Curtailments and special termination benefits			$ 8.0	6.0
Fair values of pension plan assets			4,627.0	4,839.0	4,701.0
Estimated amounts of accumulated net actuarial loss that will be amortized from AOCI into net periodic benefit cost in 2012			124.0
Estimated amounts of accumulated prior service cost that will be amortized from AOCI into net periodic benefit cost in 2012			(2.0)
Contributions to defined benefit pension plans			289.0	41.0
Estimated future benefit payments in 2015			337.0
Estimated future benefit payments in 2016			276.0
Estimated future benefit payments in 2017			279.0
Estimated future benefit payments in 2018			282.0
Estimated future benefit payments in 2019			286.0
Estimated aggregate future benefits payments for the five years thereafter			1,459.0
Benefits paid			271.0	390.0
Accrued pensions			712.0	995.0
Defined Benefit Plan, Settlements, Plan Assets			17.0	4.0
Pensions | Pensions
Pension and Other Postretirement Benefits Disclosure [Line Items]
Curtailments and special termination benefits			8.0	8.0	18.0
Estimated amounts of accumulated net actuarial loss that will be amortized from AOCI into net periodic benefit cost in 2012			(125.0)	(77.0)	(102.0)
Other Postretirement Benefits
Pension and Other Postretirement Benefits Disclosure [Line Items]
Curtailments and special termination benefits			0.0	0.0
Estimated amounts of accumulated net actuarial loss that will be amortized from AOCI into net periodic benefit cost in 2012			18.0
Estimated amounts of accumulated prior service cost that will be amortized from AOCI into net periodic benefit cost in 2012			(9.0)
Estimated future benefit payments in 2015			65.0
Estimated aggregate future benefits payments for the five years thereafter			319.0
Benefits paid			52.0	44.0
Accrued pensions			$ 0.0	0.0
United States Pension Plans of US Entity, Defined Benefit
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets			7.15%
Contributions to defined benefit pension plans			$ 250.0	2.0	50.0
Foreign Pension Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets			6.10%
Contributions to defined benefit pension plans			$ 39.0	$ 39.0	$ 124.0
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year, Low end of Range			35.0
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year, High end of Range			$ 40.0
United States, Canada, Netherlands and United Kingdom
Pension and Other Postretirement Benefits Disclosure [Line Items]
Percentage of defined benefit pension plan assets market value			96.00%
U.S. Pension Settlement Charges
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Benefit Plan, Settlements, Plan Assets	$ 41.0