Guarantor Financial Information - Condensed Consolidating Statements of Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018
Net Income (Loss) Attributable to Parent [Abstract]
Sales	$ 613			$ 577			$ 1,761	$ 1,691
Cost of sales	406			376			1,168	1,088
Gross profit	207			201			593	603
Selling, general and administrative expenses	116			110			334	328
Net legacy and separation-related (income) expenses	0			(3)			3	14
Equity and other (income) expenses, net	(11)			(8)			(29)	(29)
Operating income	102			102			285	290
Net pension and other postretirement plan income	(2)			(10)			(7)	(30)
Net interest and other financing expenses	19			15			55	45
Income before income taxes	85			97			237	275
Income tax (benefit) expense	20			33			56	154
Equity in net income of subsidiaries	0			0			0	0
Net income	65	$ 63	$ 53	64	$ 67	$ (10)	181	121
Comprehensive income	63			48			173	105
Eliminations
Net Income (Loss) Attributable to Parent [Abstract]
Sales	(18)			(16)			(50)	(41)
Cost of sales	(18)			(16)			(50)	(41)
Gross profit	0			0			0	0
Selling, general and administrative expenses	0			0			0	0
Net legacy and separation-related (income) expenses	0			0			0	0
Equity and other (income) expenses, net	0			0			0	0
Operating income	0			0			0	0
Net pension and other postretirement plan income	0			0			0	0
Net interest and other financing expenses	0			0			0	0
Income before income taxes	0			0			0	0
Income tax (benefit) expense	0			0			0	0
Equity in net income of subsidiaries	88			83			245	215
Net income	(88)			(83)			(245)	(215)
Comprehensive income	(87)			(56)			(235)	(191)
Valvoline Inc. (Parent Issuer) | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales	0			0			0	0
Cost of sales	0			0			0	0
Gross profit	0			0			0	0
Selling, general and administrative expenses	3			3			8	10
Net legacy and separation-related (income) expenses	0			(3)			3	4
Equity and other (income) expenses, net	0			0			0	0
Operating income	(3)			0			(11)	(14)
Net pension and other postretirement plan income	0			0			0	0
Net interest and other financing expenses	17			14			47	39
Income before income taxes	(20)			(14)			(58)	(53)
Income tax (benefit) expense	(5)			(1)			(16)	16
Equity in net income of subsidiaries	(80)			(77)			(223)	(190)
Net income	65			64			181	121
Comprehensive income	63			48			173	105
Guarantor Subsidiaries | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales	491			456			1,396	1,319
Cost of sales	324			294			917	832
Gross profit	167			162			479	487
Selling, general and administrative expenses	87			81			258	247
Net legacy and separation-related (income) expenses	0			0			0	10
Equity and other (income) expenses, net	(16)			(11)			(43)	(37)
Operating income	96			92			264	267
Net pension and other postretirement plan income	(2)			(10)			(7)	(30)
Net interest and other financing expenses	2			1			5	4
Income before income taxes	96			101			266	293
Income tax (benefit) expense	24			30			65	128
Equity in net income of subsidiaries	(8)			(6)			(22)	(25)
Net income	80			77			223	190
Comprehensive income	78			61			215	174
Non-Guarantor Subsidiaries | Reportable Legal Entities
Net Income (Loss) Attributable to Parent [Abstract]
Sales	140			137			415	413
Cost of sales	100			98			301	297
Gross profit	40			39			114	116
Selling, general and administrative expenses	26			26			68	71
Net legacy and separation-related (income) expenses	0			0			0	0
Equity and other (income) expenses, net	5			3			14	8
Operating income	9			10			32	37
Net pension and other postretirement plan income	0			0			0	0
Net interest and other financing expenses	0			0			3	2
Income before income taxes	9			10			29	35
Income tax (benefit) expense	1			4			7	10
Equity in net income of subsidiaries	0			0			0	0
Net income	8			6			22	25
Comprehensive income	$ 9			$ (5)			$ 20	$ 17