Note 4 - Long-term Debt - Aggregate Minimum Principal Maturities on Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Remainder of 2021	$ 0
2022	0
2023	0
2024	595
2025	0
2026	1,890
Thereafter	1,550
Total Debt	4,035	$ 4,035
The 2019 Senior Credit Facility [Member]
Remainder of 2021	0
2022	0
2023	0
2024	595
2025	0
2026	1,190
Thereafter	0
Total Debt	1,785
2026 Notes [Member]
Remainder of 2021	0
2022	0
2023	0
2024	0
2025	0
2026	700
Thereafter	0
Total Debt	700	700
2027 Notes [Member]
Remainder of 2021	0
2022	0
2023	0
2024	0
2025	0
2026	0
Thereafter	750
Total Debt	750	750
2030 Notes [Member]
Remainder of 2021	0
2022	0
2023	0
2024	0
2025	0
2026	0
Thereafter	800
Total Debt	$ 800	$ 800

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 of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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