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Fair Value Disclosures (Nonrecurring Fair Value Measurements, Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2020 USD ($)	Feb. 29, 2020 USD ($)	Aug. 31, 2020 USD ($) ft² Sites Taxlot
Vitesse Energy Finance
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties	$ 13.2		$ 13.2
Vitesse Energy Finance \| Oil and Gas Properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of proven oil and gas properties	$ 26.8
Vitesse Energy Finance \| Discount Rate \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value measurement input	0.100
JETX Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties		$ 33.0	$ 33.0
JETX Energy \| Oil and Gas Properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of proven oil and gas properties		$ 9.6
JETX Energy \| Discount Rate \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value measurement input		0.100
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 \| RedSky JZ Fulton Mall \| Development site
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investment, ownership percentage			49.00%