Fair Value of Financial Instruments (Details) (USD $)	Nov. 30, 2012	Nov. 30, 2011
Fair Value of Financial Instruments
Fair value of the long-term debt	$ 144,600,000	$ 145,800,000
Carrying value of the long-term debt	128,600,000	134,400,000
Recurring basis | Level 1
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,000	3,000
Recurring basis | Level 1 | Foreign Currency Forward Contracts
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,000	3,000
Recurring basis | Level 2
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,742,000	2,162,000
Recurring basis | Level 2 | Interest Rate Contracts
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,742,000	2,162,000
Recurring basis | Total
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,744,000	2,165,000
Recurring basis | Total | Foreign Currency Forward Contracts
Assets and liabilities measured at fair value
Fair Value of Liabilities	2,000	3,000
Recurring basis | Total | Interest Rate Contracts
Assets and liabilities measured at fair value
Fair Value of Liabilities	$ 2,742,000	$ 2,162,000