Loans to and Investments in Associated Companies Loans to and Investments in Associated Companies - Real Estate Associated Companies (Details)	12 Months Ended
Nov. 30, 2019 ft² Seat Taxlot Sites
Investment [Line Items]
Number of separate tax lots \| Taxlot	15
Number of premier development sites \| Sites	2
Area of real estate property (up to) \| ft²	540,000
Number of seats in investment committee retained by Company	2
Number of seats in investment committee	4
Real Estate Equity Method Investments
Investment [Line Items]
Weighted average useful life	38 years
54 Madison
Investment [Line Items]
Equity method investment, ownership percentage	48.10%
Number of seats in investment committee retained by Company	2
Number of seats in investment committee	4
Development Site \| RedSky JZ Fulton Holdings, LLC
Investment [Line Items]
Equity method investment, ownership percentage	49.00%
HomeFed Associated Companies \| Hotel \| HomeFed Associated Companies
Investment [Line Items]
Equity method investment, ownership percentage	25.80%
HomeFed Associated Companies \| Office Building \| HomeFed Associated Companies
Investment [Line Items]
Equity method investment, ownership percentage	61.25%

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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