Related Party Transactions - Ashland Costs Allocated (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline	$ 0	$ 21
Ashland | Information technology
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		5
Ashland | Financial and accounting
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		3
Ashland | Building services
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		3
Ashland | Legal and environmental
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		2
Ashland | Human resources
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		1
Ashland | Shared services
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		1
Ashland | Other general and administrative
Related Party Transaction [Line Items]
General corporate expenses allocated to Valvoline		$ 6