Accounts Payable, Accrued Liabilities and Other Liabilities - Components of Other Long-Term Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Payables And Accruals [Abstract]
Employee benefit plan liabilities	$ 173	$ 138
Non-current tax liabilities	19	17
Other accrued liabilities	93	85
Total	$ 285	$ 240