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Stockholders' Equity - Additional Information (Detail) (Sixth Share Repurchase Program, USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Nov. 30, 2013
Sixth Share Repurchase Program
Stockholders Equity Note [Line Items]
Share repurchase program, authorized amount		$ 300
Share repurchase program, remaining authorized repurchase amount	$ 120

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- Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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