Reportable Segment Information - Financial Information by Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Sales	$ 629	$ 613	$ 591	$ 557	$ 594	$ 577	$ 569	$ 545	$ 2,390	$ 2,285	$ 2,084
Operating income	$ 113	$ 102	$ 96	$ 87	$ 105	$ 102	$ 100	$ 88	398	395	394
Depreciation and amortization									61	54	42
Quick Lubes
Segment Reporting Information [Line Items]
Sales									822
Core North America
Segment Reporting Information [Line Items]
Sales									994
International
Segment Reporting Information [Line Items]
Sales									574
Operating Segments
Segment Reporting Information [Line Items]
Operating income									415	409	405
Operating Segments | Quick Lubes
Segment Reporting Information [Line Items]
Sales									822	660	541
Operating income									178	153	130
Depreciation and amortization									36	30	22
Operating Segments | Core North America
Segment Reporting Information [Line Items]
Sales									994	1,035	1,004
Operating income									152	172	199
Depreciation and amortization									18	18	15
Operating Segments | International
Segment Reporting Information [Line Items]
Sales									574	590	539
Operating income									85	84	76
Depreciation and amortization									7	6	5
Unallocated and Other
Segment Reporting Information [Line Items]
Operating income									$ (17)	$ (14)	$ (11)