Fair Value Measurements - Discount Rate Used to Estimate Fair Value of Investment in Partnership (Details)	3 Months Ended
	Feb. 29, 2020 USD ($)	Feb. 28, 2019 USD ($)	Nov. 30, 2019 USD ($)	[1]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in limited partnership	$ 143,201,000		$ 137,849,000
Change in Value	$ 7,351,000	$ 0
Discount rate | 0.50% Decrease
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Weighted Average Rate	0.1407
Investment in limited partnership	$ 147,095,000
Change in Value	$ 3,894,000
Discount rate | No Change
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Weighted Average Rate	0.1457
Investment in limited partnership	$ 143,201,000
Change in Value	$ 0
Discount rate | 0.50% Increase
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Weighted Average Rate	0.1507
Investment in limited partnership	$ 139,459,000
Change in Value	$ (3,742,000)

[1] Derived from audited consolidated financial statements.