Discontinued Operations - Reconciliation of Consolidated Income (Loss) From Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income (loss) from discontinued operations attributable to Composites/Marl facility
Research and development expense	$ (17)	$ (19)
Income tax expense	(24)	(10)
Income from discontinued operations	23	28
Composites/Marl facility [Member]
Income (loss) from discontinued operations attributable to Composites/Marl facility
Sales	275	261
Cost of sales	(217)	(211)
Selling, general and administrative expense	(22)	(17)
Research and development expense	(3)	(2)
Equity and other income	3	3
Pretax operating income of discontinued operations	36	34
Net interest and other financing expense	(6)	(4)
Pretax income of discontinued operations	30	30
Income tax expense	(5)	(5)
Income from discontinued operations	$ 25	$ 25

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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