Note 4 - Long-term Debt - Long-term Debt Summary (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018	Nov. 16, 2018
Long-term Debt, Gross	$ 3,960	$ 2,570
Total outstanding principal	3,960	2,570
Long-term debt, less deferred financing costs	3,895	2,549
Less current portion	(14)	0
Net carrying value	3,881	2,549
Borrowing availability under Revolving Credit Facility	200	100
The 2017 Term Loan [Member]
Long-term Debt, Gross	595	595
Total outstanding principal	595	595
Unamortized deferred loan costs	0	(9)
The 2019 Term Loan [Member]
Long-term Debt, Gross	1,390	0
Total outstanding principal	1,390	0
Unamortized deferred loan costs	(45)	0
2024 Notes [Member]
Long-term Debt, Gross	525	525
Total outstanding principal	525	525
Unamortized deferred loan costs	(5)	(6)
2026 Notes [Member]
Long-term Debt, Gross	700	700
Total outstanding principal	700	700
Unamortized deferred loan costs	(8)	(8)
Unamortized premium	4	4
2027 Notes [Member]
Long-term Debt, Gross	750	750	$ 750
Total outstanding principal	750	750	$ 750
Unamortized deferred loan costs	$ (11)	$ (2)

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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