Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 2,880,000	$ 2,900,000	$ 2,900,000
Debt issuance costs and debt discount	(37,268)	(45,336)	(51,076)
Long-term debt	2,837,732	2,854,664	2,848,924
Senior Notes \| 2010 Senior Notes due October 2040
Debt Instrument [Line Items]
Long-term debt	250,000	250,000	250,000
Senior Notes \| 2011 Senior Notes due November 2041
Debt Instrument [Line Items]
Long-term debt	300,000	300,000	300,000
Senior Notes \| 2013 Senior Notes due March 2023
Debt Instrument [Line Items]
Long-term debt	250,000	250,000	250,000
Senior Notes \| 2017/2018 Senior Notes due December 2025
Debt Instrument [Line Items]
Long-term debt	275,000	1,500,000	1,500,000
Senior Notes \| 2019 Senior Notes due December 2027
Debt Instrument [Line Items]
Long-term debt	600,000	600,000	600,000
Senior Notes \| 2021 Senior Notes due April 2026
Debt Instrument [Line Items]
Long-term debt	600,000	0	0
Senior Notes \| 2021 Senior Notes due April 2029
Debt Instrument [Line Items]
Long-term debt	$ 600,000	$ 0	$ 0

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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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