Long-Term Debt - FV, Limit, Interest Expense (Details) $ in Thousands	Nov. 30, 2016 USD ($)
Long-term debt
Limit on additional debt borrowings	$ 180,770
3.90% unsecured Senior Notes payable \| Book value
Long-term debt
Long-term debt	39,690
3.90% unsecured Senior Notes payable \| Fair Values \| Significant Other Observable Market Inputs (Level 2) \| Discounted cash flow analysis
Long-term debt
Long-term debt	$ 40,310

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

No definition available.

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant