Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

Goodwill And Other Intangible Assets (Schedule Of Goodwill Balances) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011
Goodwill [Line Items]
Total goodwill	$ 40	$ 40
Rubber Blacks [Member]
Goodwill [Line Items]
Total goodwill	27
Fumed Metal Oxides Business [Member]
Goodwill [Line Items]
Total goodwill	11
Security Materials [Member]
Goodwill [Line Items]
Total goodwill	$ 2