Seasonal Financing and Debt - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Nov. 30, 2019
Debt Instrument [Line Items]
Gross, long-term debt	$ 2,900,000	$ 2,900,000
Debt issuance costs and debt discount	(45,336)	(53,249)
Long-term debt	2,854,664	2,846,751
Less: current portion	0	0
Total long-term debt	$ 2,854,664	2,846,751
2010 Senior Notes due October 2020 and October 2040 \| Senior Notes
Debt Instrument [Line Items]
Interest Rate	6.20%
Gross, long-term debt	$ 250,000	250,000
2011 Senior Notes due November 2041 \| Senior Notes
Debt Instrument [Line Items]
Interest Rate	5.45%
Gross, long-term debt	$ 300,000	300,000
2013 Senior Notes due March 2023 \| Senior Notes
Debt Instrument [Line Items]
Interest Rate	3.15%
Gross, long-term debt	$ 250,000	250,000
2017/2018 Senior Notes due December 2025 \| Senior Notes
Debt Instrument [Line Items]
Interest Rate	6.75%
Gross, long-term debt	$ 1,500,000	1,500,000
2019 Senior Notes due December 2027 \| Senior Notes
Debt Instrument [Line Items]
Interest Rate	5.875%		5.875%
Gross, long-term debt	$ 600,000	$ 600,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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