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Long-Term Debt - Additional Information (Detail) - USD ($)		12 Months Ended
	Nov. 22, 2017	Nov. 30, 2017	Nov. 30, 2016	Nov. 30, 2015	Jan. 31, 2018	Jan. 23, 2018
Debt Instrument [Line Items]
Long-term borrowings matured or retired during period			$ 350,000,000	$ 500,000,000
Proceeds from the issuance of long-term debt		$ 1,116,798,000	299,779,000	0
Long-term debt		6,416,844,000	5,483,355,000
Redemption price as percentage of principal amount redeemed	100.00%
Senior notes
Debt Instrument [Line Items]
Debt principal amount		609,100,000
3.875% Convertible Senior Debentures due 2029
Debt Instrument [Line Items]
Debt principal amount		$ 345,000,000.0
Debt instrument interest rate		3.875%
Long-term borrowings matured or retired during period		$ 20,200,000
3.875% Convertible Senior Debentures due 2029 \| Unsecured debt
Debt Instrument [Line Items]
Debt instrument interest rate		3.875%
Long-term debt		$ 324,779,000	346,187,000
Structured notes \| Unsecured debt
Debt Instrument [Line Items]
Debt principal amount		329,900,000	275,400,000
Proceeds from the issuance of long-term debt				$ 0
Long-term debt		$ 614,091,000	255,203,000
5.125% Senior Notes \| Unsecured debt
Debt Instrument [Line Items]
Debt instrument interest rate		5.125%
Long-term debt		$ 682,338,000	817,813,000
Subsequent event \| 4.150% Senior Notes \| Senior notes
Debt Instrument [Line Items]
Debt principal amount						$ 1,000,000,000.0
Debt instrument interest rate						4.15%
Leucadia \| Affiliated Entity
Debt Instrument [Line Items]
Payable to Leucadia		$ 3,100,000	$ 1,900,000
Leucadia \| Affiliated Entity \| Subsequent event
Debt Instrument [Line Items]
Payable to Leucadia					$ 200,000,000