Guarantor Financial Information - Condensed Consolidating Statements of Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Net Income (Loss) Attributable to Parent [Abstract]
Sales	$ 594	$ 577	$ 569	$ 545	$ 547	$ 534	$ 514	$ 489	$ 2,285	$ 2,084	$ 1,929
Cost of sales									1,479	1,308	1,181
Gross profit	203	201	207	195	196	197	198	185	806	776	748
Selling, general and administrative expenses									430	396	365
Legacy and separation-related expenses, net									14	11	6
Equity and other income, net									(33)	(25)	(19)
Operating income	105	102	100	88	113	87	100	94	395	394	396
Net pension and other postretirement plan expense (income)									0	(138)	(35)
Net interest and other financing expenses									63	42	9
Net loss on acquisition									0	0	1
Income before income taxes									332	490	421
Income tax expense	2	3	2	71					166	186	148
Equity in net income of subsidiaries									0	0	0
Net income	$ 45	$ 64	$ 67	$ (10)	$ 105	$ 56	$ 71	$ 72	166	304	273
Total comprehensive income									147	303	280
Eliminations
Net Income (Loss) Attributable to Parent [Abstract]
Sales									(55)	(57)	(47)
Cost of sales									(55)	(57)	(47)
Gross profit									0	0	0
Selling, general and administrative expenses									0	0	0
Legacy and separation-related expenses, net									0	0	0
Equity and other income, net									0	0	0
Operating income									0	0	0
Net pension and other postretirement plan expense (income)									0	0	0
Net interest and other financing expenses									0	0	0
Net loss on acquisition											0
Income before income taxes									0	0	0
Income tax expense									0	0	0
Equity in net income of subsidiaries									284	363	322
Net income									(284)	(363)	(322)
Total comprehensive income									(259)	(373)	(338)
Valvoline Inc. (Parent Issuer) | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales									0	0	0
Cost of sales									0	0	0
Gross profit									0	0	0
Selling, general and administrative expenses									11	9	0
Legacy and separation-related expenses, net									8	(15)	0
Equity and other income, net									0	0	0
Operating income									(19)	6	0
Net pension and other postretirement plan expense (income)									0	0	0
Net interest and other financing expenses									53	36	9
Net loss on acquisition											0
Income before income taxes									(72)	(30)	(9)
Income tax expense									14	(3)	(4)
Equity in net income of subsidiaries									(252)	(331)	(278)
Net income									166	304	273
Total comprehensive income									147	303	280
Guarantor Subsidiaries | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales									1,782	1,618	1,500
Cost of sales									1,132	986	895
Gross profit									650	632	605
Selling, general and administrative expenses									327	296	285
Legacy and separation-related expenses, net									6	26	6
Equity and other income, net									(50)	(37)	(21)
Operating income									367	347	335
Net pension and other postretirement plan expense (income)									1	(134)	(43)
Net interest and other financing expenses									6	4	0
Net loss on acquisition											1
Income before income taxes									360	477	377
Income tax expense									140	178	143
Equity in net income of subsidiaries									(32)	(32)	(44)
Net income									252	331	278
Total comprehensive income									234	330	285
Non-Guarantor Subsidiaries | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales									558	523	476
Cost of sales									402	379	333
Gross profit									156	144	143
Selling, general and administrative expenses									92	91	80
Legacy and separation-related expenses, net									0	0	0
Equity and other income, net									17	12	2
Operating income									47	41	61
Net pension and other postretirement plan expense (income)									(1)	(4)	8
Net interest and other financing expenses									4	2	0
Net loss on acquisition											0
Income before income taxes									44	43	53
Income tax expense									12	11	9
Equity in net income of subsidiaries									0	0	0
Net income									32	32	44
Total comprehensive income									$ 25	$ 43	$ 53