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Stock Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Stock Repurchase Program
Authorized amount of stock repurchase	$ 1,000.0
Shares repurchased and retired under the agreement		27.4
Average price per share of stock repurchased under the agreement (in dollars per share)		$ 24.10
Total cost of shares repurchased under the agreement	$ 0.0	$ 660.1

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef



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-Name Accounting Standards Codification



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-SubTopic 10



-Section 50



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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



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Total cost of shares repurchased divided by the total number of shares repurchased.

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-Name Accounting Standards Codification



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