Income Taxes (Details) - USD ($)	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Nov. 30, 2019
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax expense	$ 9,100,000	$ 4,500,000
Effective tax rate	13.20%	13.00%
Net (increase) reduction in valuation allowance		$ 3,300,000
Excess tax benefits related to stock-based compensation	$ (5,600,000)	(2,000,000.0)
Tax credits	(4,000,000.0)	800,000
Deferred tax assets	331,400,000		$ 383,700,000
Valuation allowance	19,200,000		19,200,000
Deferred Tax Assets, Tax Credit Carryforwards	43,322,000	$ 0
Adjustments to deferred tax valuation allowance	0
Gross unrecognized tax benefits (including interest and penalties)	$ 0		$ 0

Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount - Other

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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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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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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