Note 4 - Long-term Debt - Aggregate Minimum Principal Maturities on Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Remainder of 2020	$ 0
2021	0
2022	0
2023	0
2024	1,120
2025	0
Thereafter	2,640
Total Debt	3,760	$ 3,760
The 2019 Senior Credit Facility [Member]
Remainder of 2020	0
2021	0
2022	0
2023	0
2024	595
2025	0
Thereafter	1,190
Total Debt	1,785
2024 Notes [Member]
Remainder of 2020	0
2021	0
2022	0
2023	0
2024	525
2025	0
Thereafter	0
Total Debt	525	525
2026 Notes [Member]
Remainder of 2020	0
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	700
Total Debt	700	700
2027 Notes [Member]
Remainder of 2020	0
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	750
Total Debt	$ 750	$ 750

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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