Mortgage Loan (Details) $ in Thousands										3 Months Ended			12 Months Ended
	Jan. 20, 2017 building	Nov. 17, 2016 USD ($) ft² derivative	Apr. 26, 2016 USD ($) ft² building	Dec. 11, 2015 USD ($) subsidiary	Dec. 10, 2015 USD ($)	Sep. 01, 2015 USD ($) ft² subsidiary	Jul. 29, 2015 USD ($) ft² building	Dec. 31, 2014 USD ($) ft² derivative	Jun. 06, 2014 USD ($) ft²	Nov. 30, 2016 USD ($) item	May 31, 2016 USD ($)	Nov. 30, 2015 USD ($) ft²	Nov. 30, 2016 USD ($) item	Nov. 30, 2015 USD ($) ft²	Nov. 30, 2014 USD ($)
Long-Term Debt
Mortgage loans, prior to debt issuance costs										$ 111,139		$ 90,436	$ 111,139	$ 90,436
Debt issuance costs, net										(1,442)		(1,251)	(1,442)	(1,251)
Mortgage loans, net										109,697		89,185	109,697	89,185
Debt disclosures
Other Assets										14,186		14,098	14,186	14,098
Proceeds from issuance of debt													45,525	40,391	$ 5,477
Funds placed in (returned from) escrow													$ (600)	600	1,000
Prepayment prohibition period													7 years
Ineffectiveness on cash flow hedges													$ 0
Anticipated ineffectiveness on cash flow hedges													0
Net fair values of interest rate swap agreements										1,685			1,685
Loss on debt extinguishment															(51)
Subsequent events
Debt disclosures
Number of buildings used as collateral | building	2
Term of debt	10 years
Amortization period of debt	25 years
Other assets
Debt disclosures
Net fair values of interest rate swap agreements										207			207
Other liabilities caption
Debt disclosures
Net fair values of interest rate swap agreements										1,892		2,766	1,892	2,766
Accounting Standards Update 2015-03 [Member] | Restatement Adjustment [Member]
Long-Term Debt
Mortgage loans, net										(1,442)		(1,251)	(1,442)	(1,251)
Debt disclosures
Other Assets										(1,442)		(1,251)	(1,442)	(1,251)
Nonrecourse variable rate loans, due October 2, 2017
Long-Term Debt
Mortgage loans, prior to debt issuance costs										6,034		6,217	6,034	6,217
Nonrecourse variable rate loans, due February 1, 2019
Long-Term Debt
Mortgage loans, prior to debt issuance costs										10,313		10,610	10,313	10,610
Nonrecourse variable rate loans, due August 1, 2019
Long-Term Debt
Mortgage loans, prior to debt issuance costs			$ 7,418									7,501		7,501
Debt disclosures
Number of buildings used as collateral | building			4
Area of collateralized properties (in square feet) | ft²			240,000
Debt amount refinanced			$ 7,418
Nonrecourse variable rate loans, due January 27, 2020
Long-Term Debt
Mortgage loans, prior to debt issuance costs										3,606		3,729	3,606	3,729
Nonrecourse variable rate loans, due January 2, 2025
Long-Term Debt
Mortgage loans, prior to debt issuance costs										20,744		19,385	20,744	19,385
Debt disclosures
Proceeds from issuance of debt				$ 1,850				$ 10,891
Term of debt								10 years
Amortization period of debt								25 years
Number of subsidiaries which are party to the mortgage | subsidiary				2
Debt amount refinanced								$ 8,859
Nonrecourse variable rate mortgage, due September 1, 2025
Long-Term Debt
Mortgage loans, prior to debt issuance costs												11,457		11,457
Debt disclosures
Proceeds from issuance of debt					$ 2,600	$ 11,500
Term of debt						10 years
Amortization period of debt						25 years
Leased space | ft²						196,000
Number of subsidiaries which are party to the mortgage | subsidiary						1
Nonrecourse Variable Rate Mortgage, Refinanced, Due In September 2026 [Member]
Long-Term Debt
Mortgage loans, prior to debt issuance costs		$ 26,725
Debt disclosures
Proceeds from issuance of debt		$ 13,000
Term of debt		10 years
Amortization period of debt		25 years
Debt amount refinanced		$ 13,725
Nonrecourse Variable Rate Mortgage Due On 1 May 2026 [Member]
Long-Term Debt
Mortgage loans, prior to debt issuance costs										14,187			14,187
Debt disclosures
New mortgage			$ 14,350
Number of buildings used as collateral | building			4
Proceeds from issuance of debt			$ 6,932
Term of debt			10 years
Amortization period of debt			25 years
Additional area serving as collateral | ft²			98,000
Nonrecourse Variable Rate Mortgage Due On November 17, 2026 [Member]
Long-Term Debt
Mortgage loans, prior to debt issuance costs										26,725			26,725
5.09%, due July 1, 2029 GCD mortgage loan
Long-Term Debt
Mortgage loans, prior to debt issuance costs									$ 7,868	$ 7,001		7,385	$ 7,001	7,385
Interest rate (as a percent)									5.09%	5.09%			5.09%
Debt disclosures
Area of collateralized properties (in square feet) | ft²									165,000
Term of debt									15 years
Amortization period of debt									15 years
5.09%, due July 1, 2029 TD mortgage Loan
Long-Term Debt
Mortgage loans, prior to debt issuance costs									$ 6,632	$ 4,905		6,226	$ 4,905	6,226
Interest rate (as a percent)									5.09%	5.09%			5.09%
Debt disclosures
Funds placed in (returned from) escrow									$ 1,000
Term of debt									15 years
Amortization period of debt									15 years
Prepayment using funds released from escrow										$ 1,000
4.33%, due August 1, 2030 mortgage loan
Long-Term Debt
Mortgage loans, prior to debt issuance costs							$ 18,000			$ 17,624		17,926	$ 17,624	$ 17,926
Interest rate (as a percent)										4.33%			4.33%
Debt disclosures
Number of buildings used as collateral | building							3
Proceeds from issuance of debt							$ 14,875
Funds placed in (returned from) escrow							$ 3,125					$ (2,500)
Term of debt							15 years
Amortization period of debt							30 years
Nonrecourse mortgages: 5.73%, due August 1, 2015
Long-Term Debt
Interest rate (as a percent)							5.73%
Debt disclosures
Number of buildings used as collateral | building							3
Area of collateralized properties (in square feet) | ft²							392,000
Debt amount refinanced							$ 17,891
Nonrecourse Mortgage 8.13 Percent Due 1 April 2016 [Member]
Long-Term Debt
Interest rate (as a percent)									8.13%
Debt disclosures
Debt amount refinanced									$ 3,391
Nonrecourse Mortgage 7.0 Percent Due 1 October 2017 [Member]
Long-Term Debt
Interest rate (as a percent)									7.00%
Debt disclosures
Debt amount refinanced									$ 5,632
First Collateralized Property | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Area of collateralized properties (in square feet) | ft²								303,000
Leased space | ft²								201,000
First Collateralized Property | Nonrecourse Variable Rate Mortgage, Refinanced, Due In September 2026 [Member]
Debt disclosures
Area of collateralized properties (in square feet) | ft²		280,000
First Collateralized Property | Nonrecourse Variable Rate Mortgage Due On 1 May 2026 [Member]
Debt disclosures
Leased space | ft²			58,000
First Collateralized Property | 5.09%, due July 1, 2029 TD mortgage Loan
Debt disclosures
Area of collateralized properties (in square feet) | ft²									100,000
First Collateralized Property | 4.33%, due August 1, 2030 mortgage loan
Debt disclosures
Leased space | ft²												88,000		88,000
Second Collateralized Property | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Area of collateralized properties (in square feet) | ft²								228,000
Second Collateralized Property | Nonrecourse Variable Rate Mortgage, Refinanced, Due In September 2026 [Member]
Debt disclosures
Area of collateralized properties (in square feet) | ft²		252,000
Second Collateralized Property | Nonrecourse Variable Rate Mortgage Due On 1 May 2026 [Member]
Debt disclosures
Leased space | ft²			40,000
Second Collateralized Property | 5.09%, due July 1, 2029 TD mortgage Loan
Debt disclosures
Area of collateralized properties (in square feet) | ft²									57,000
Second Collateralized Property | 4.33%, due August 1, 2030 mortgage loan
Debt disclosures
Funds placed in (returned from) escrow											$ (600)
Interest rate swap agreement
Debt disclosures
Number of agreements containing credit risk related contingent features | item										0			0
Recognized net losses (included in other comprehensive loss), before taxes, on interest rate swap agreements													$ 1,081	$ (444)	$ (100)
Loss expected to be reclassified over next twelve months from accumulated other comprehensive loss to interest expense										$ (1,223)			(1,223)
Interest rate swap agreement | Nonrecourse variable rate loans, due August 1, 2019
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)			6.58%
Interest rate swap agreement | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)								4.39%
Number of interest rate swap derivatives | derivative								3
Interest rate swap agreement | Nonrecourse Variable Rate Mortgage, Refinanced, Due In September 2026 [Member]
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)		3.79%
Number of interest rate swap derivatives | derivative		2
Interest rate swap agreement | Nonrecourse Variable Rate Mortgage Due On 1 May 2026 [Member]
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)			4.17%
Nonrecourse Mortgage, Proceeds Excluding Contingent Portion [Member] | First Collateralized Property | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Leased space | ft²								102,000
Nonrecourse Mortgage, Proceeds Excluding Contingent Portion [Member] | Interest rate swap agreement | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)								4.43%
Nonrecourse Mortgage, Proceeds Excluding Contingent Portion [Member] | Interest rate swap agreement | Nonrecourse variable rate mortgage, due September 1, 2025
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)						3.77%
Notional amount of interest rate swap agreement						$ 11,500
Nonrecourse Mortgage, Contingent Portion [Member] | 4.33%, due August 1, 2030 mortgage loan
Debt disclosures
Funds placed in (returned from) escrow							$ (25)
Nonrecourse Mortgage, Contingent Portion [Member] | Interest rate swap agreement | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)								3.88%
Notional amount of interest rate swap agreement								$ 1,850
Nonrecourse Mortgage, Contingent Portion [Member] | Interest rate swap agreement | Nonrecourse variable rate mortgage, due September 1, 2025
Debt disclosures
Fixed interest rate pursuant to interest rate swap agreement (as a percent)						3.67%
Notional amount of interest rate swap agreement						$ 2,600
Mortgages [Member]
Annual principal payment requirements under the terms of the nonrecourse mortgage loans
2017										8,994			8,994
2018										3,100			3,100
2019										12,552			12,552
2020										6,077			6,077
2021										3,004			3,004
Debt disclosures
Aggregate book value of land and buildings pledged as collateral										$ 125,600			$ 125,600
LIBOR
Debt disclosures
Variable interest rate margin (as a percent)													2.75%
LIBOR | Subsequent events
Debt disclosures
Variable interest rate margin (as a percent)	1.95%
LIBOR | Nonrecourse variable rate loans, due August 1, 2019
Debt disclosures
Variable interest rate margin (as a percent)			3.08%
LIBOR | Nonrecourse variable rate loans, due January 2, 2025
Debt disclosures
Variable interest rate margin (as a percent)								1.95%
LIBOR | Nonrecourse variable rate mortgage, due September 1, 2025
Debt disclosures
Variable interest rate margin (as a percent)						1.65%
LIBOR | Nonrecourse Variable Rate Mortgage, Refinanced, Due In September 2026 [Member]
Debt disclosures
Variable interest rate margin (as a percent)		1.70%
LIBOR | Nonrecourse Variable Rate Mortgage Due On 1 May 2026 [Member]
Debt disclosures
Variable interest rate margin (as a percent)			2.00%