Business Restructuring (Schedule of Restructuring Activity) (Details)	3 Months Ended			9 Months Ended		12 Months Ended	15 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) employee	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) employee position	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) employee	Jun. 30, 2019 USD ($)
Restructuring Cost and Reserve [Line Items]
Business restructuring charge	$ (12,000,000)		$ 0	$ 71,000,000	$ 0
Restructuring and related cost, accelerated depreciation	4,000,000		$ 0	$ 9,000,000	$ 0
Employees Impacted | employee				269		949
Number Of Employees Included In Plan Who Ceased Employment In Period | employee				(680)
Employee Severance
Restructuring Cost and Reserve [Line Items]
Business restructuring charge				$ 48,000,000
Restructuring Reserve, Translation Adjustment				(3,000,000)
Restructuring Reserve	51,000,000			$ 51,000,000		$ 102,000,000
2016 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected number of positions eliminated | position				2,000
2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Business restructuring charge	83,000,000			$ 9,000,000
Restructuring and related cost, expected cost	25,000,000			25,000,000
Restructuring and related cost, cost expensed on an as-incurred basis	10,000,000			10,000,000
Restructuring and related cost, cost expected to be capitalized	$ 15,000,000			$ 15,000,000
Employees Impacted	1,243	1,678
Number Of Employees Included In Plan Who Ceased Employment In Period				(435)
Restructuring Reserve	$ 74,000,000	$ 83,000,000		$ 74,000,000
2018 Restructuring Program | Employee Severance And Other Cost
Restructuring Cost and Reserve [Line Items]
Severance Costs	80,000,000
2018 Restructuring Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Business restructuring charge				6,000,000
Restructuring Reserve	74,000,000	80,000,000		74,000,000
2018 Restructuring Program | Asset Write Offs Or Other
Restructuring Cost and Reserve [Line Items]
Business restructuring charge				3,000,000
Restructuring Reserve	$ 0	3,000,000		$ 0
Performance Coatings | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 52,000,000
Employees Impacted | employee		1,032
Performance Coatings | 2018 Restructuring Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 49,000,000
Performance Coatings | 2018 Restructuring Program | Asset Write Offs Or Other
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		3,000,000
Industrial Coatings | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 21,000,000
Employees Impacted | employee		298
Industrial Coatings | 2018 Restructuring Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 21,000,000
Industrial Coatings | 2018 Restructuring Program | Asset Write Offs Or Other
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		0
Corporate Segment | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 10,000,000
Employees Impacted | employee		348
Corporate Segment | 2018 Restructuring Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 10,000,000
Corporate Segment | 2018 Restructuring Program | Asset Write Offs Or Other
Restructuring Cost and Reserve [Line Items]
Business restructuring charge		$ 0
Scenario, Forecast
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, accelerated depreciation							$ 20,000,000