Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2013	Aug. 31, 2012
Income Taxes [Line Items]
Liability for uncertain tax positions, inclusive of tax, interest, and penalties	$ 2.5		$ 2.5
If the accrued liability for uncertain tax positions was de-recognized, the amount that would reduce the effective tax rate	1.3		1.3
Tax deductions with uncertain timing	0.7		0.7
If the tax benefits with uncertain timing were de-recognized, effect on effective income tax rate	0		0
Accrued interest related to uncertain tax positions	0.5		0.5
Accrued penalties related to uncertain tax positions	0		0
If the accrued interest and penalties related to uncertain tax positions were de-recognized, amount that would reduce effective tax rate	0.3		0.3
Effective income tax rate	42.90%	51.30%	37.40%	36.90%
State
Income Taxes [Line Items]
Liability for uncertain tax positions, inclusive of tax, interest, and penalties	$ 2.0		$ 2.0