Income Tax (Tables)

6 Months Ended

Mar. 31, 2017

Income Tax Disclosure [Abstract]

Effective Tax Rate

Effective Tax Rate

	Three Months Ended						Six Months Ended
	March 31,						March 31,
	2017			2016			2017			2016
	(Dollars in millions)
Provision (benefit) for income taxes	$	(1	)	$	11		$	16		$	6
Effective tax rate		(1	)%		20	%		11	%		12	%