Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Effective tax rate	36.00%	16.00%	38.00%
Undistributed earnings of foreign subsidiaries	$ 19
Operating loss carryforwards	24
Operating loss carryforwards, valuation allowance		$ 7
Operating loss carryforwards, expiration date	2031
Decrease in unrecognized tax benefits due to expiration of certain statutes of limitations	1.00%

Operating losses carryforward expiration year.

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- Definition

Unrecognized tax benefits percentage reductions resulting from lapse of applicable statute of limitations.

+ References

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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