Supplemental Financial Statement Information - Liabilities (Details) - USD ($)	Nov. 30, 2020	Dec. 01, 2019	Nov. 30, 2019
Accounts Payable and Accrued Liabilities
Accrued salaries, wages and other compensation	$ 1,130,000		$ 863,000
Trade payables	914,000		295,000
Accrued interest payable	584,000		568,000
Accrued construction costs and retainage	439,000		1,849,000
Accrued lease commissions	269,000		223,000
Other	756,000		520,000
Total accounts payable and accrued liabilities	4,092,000		4,318,000
Other Liabilities
Interest rate swap liabilities	8,962,000		4,052,000
Deferred compensation plan	4,170,000		5,593,000
Prepaid rent from tenants	1,435,000		1,013,000
Lease liabilities	$ 748,000	$ 858,000
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Lease liabilities	Total other liabilities
Intangible liability, net	$ 705,000
Security deposits of tenants	690,000		538,000
Conditional asset retirement obligations	161,000		171,000
Other	100,000		142,000
Total other liabilities	17,652,000		$ 11,509,000
Warrant Liability
Other Liabilities
Derivative liability	11,550,000
Contingent Value Rights Liability
Other Liabilities
Derivative liability	$ 681,000