Note 4 - Long-term Debt - Long-term Debt Summary (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Long-term debt, gross	$ 4,035	$ 3,760
Long-term debt, less deferred financing costs	3,974	3,697
Borrowing availability under Revolving Credit Facility	200	200
The 2017 Term Loan [Member]
Long-term debt, gross	595	595
The 2019 Term Loan [Member]
Long-term debt, gross	1,190	1,190
2024 Notes [Member]
Long-term debt, gross	0	525
Unamortized deferred loan costs	0	(5)
2026 Notes [Member]
Long-term debt, gross	700	700
Unamortized deferred loan costs	(6)	(7)
Unamortized premium	3	4
2027 Notes [Member]
Long-term debt, gross	750	750
Unamortized deferred loan costs	(10)	(11)
2030 Notes [Member]
Long-term debt, gross	800	0
Unamortized deferred loan costs	(14)	0
The 2019 Senior Credit Facility [Member]
Long-term debt, gross	1,785
Unamortized deferred loan costs	$ (34)	$ (44)

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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