Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	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, 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 expense	20	33	56	154
Net income	$ 65	$ 64	$ 181	$ 121
NET INCOME PER SHARE
Basic (usd per share)	$ 0.34	$ 0.33	$ 0.96	$ 0.61
Diluted (usd per share)	$ 0.34	$ 0.33	$ 0.96	$ 0.61
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING
Basic (shares)	189	195	189	199
Diluted (shares)	189	196	189	200
COMPREHENSIVE INCOME
Net income	$ 65	$ 64	$ 181	$ 121
Other comprehensive income (loss), net of tax
Currency translation adjustments	1	(13)	(1)	(9)
Amortization of pension and other postretirement plan prior service credit	(3)	(3)	(7)	(7)
Other comprehensive loss	(2)	(16)	(8)	(16)
Comprehensive income	$ 63	$ 48	$ 173	$ 105