Financial Information by Segment - Schedule of Income (Loss) from Continuing Operations before Income Taxes and Equity in Earnings of Affiliated Companies for Unallocated and Other (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2017	Jun. 30, 2017
Segment Reporting [Abstract]
Increase (decrease) in general unallocated income expense	$ 2	$ (4)