Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Income Taxes [Abstract]
Effective Income Tax Rate, Continuing Operations	20.00%	36.00%	28.00%	36.00%
Income Tax Impact From Remeasurement Of Deferred Taxes	$ 208,000,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)	11,000,000,000		11,000,000,000
Unrecognized Tax Benefits, Period Increase (Decrease)	33,000,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	7,000,000		7,000,000
Unrecognized Tax Benefits, Income Tax Penalties Accrued	$ 0		$ 0

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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This element represents the amount of statutory penalties accrued as of the date of the statement of financial position for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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- Definition

This element represents the amount of interest expense accrued as of the date of the statement of financial position for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

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