Income Taxes - Schedule of Income Tax (Benefit) Provision (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Aug. 31, 2014	Aug. 31, 2013	Aug. 31, 2014	Aug. 31, 2013
Income Tax Disclosure [Abstract]
Federal and state current income tax expense			$ 5.4	$ 9.6
Net deferred benefit			(5.5)	(207.2)
Impact of change in research credit estimates			1.2	(2.0)
Income tax provision (benefit)	(0.7)	(206.6)	1.1	(199.6)
Cash paid for income taxes			$ 4.6	$ 6.3

Current Federal And State Tax Expense Benefit

No definition available.

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- Definition

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

+ References

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

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