Fair Value Disclosures (Nonrecurring Fair Value Measurements) (Details) $ in Millions	3 Months Ended
Feb. 29, 2020 USD ($) ft² Taxlot Sites
RedSky JZ Fulton Mall
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investment, other than temporary impairment	$ 55.6
JETX Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties	$ 33.0
HomeFed \| RedSky JZ Fulton Mall
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of separate tax lots \| Taxlot	14
Number of premier development sites \| Sites	2
Area of property (up to) \| ft²	540,000
Equity method investment, other than temporary impairment	$ 55.6
HomeFed \| Development site \| RedSky JZ Fulton Mall
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investment, ownership percentage	49.00%
Discount Rate \| Level 3 \| JETX Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value measurement input	0.100
Oil and Gas Properties \| JETX Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of proven oil and gas properties	$ 9.6

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