Note 9 - Summary of Undiscounted Cash Flows for Next Five Years and Thereafter to Finance Lease Liabilities and Operating Lease Liabilities Recorded on Balance Sheet (Details) $ in Millions	Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating Leases, Q4 2019	$ 6
Operating Leases, 2020	27
Operating Leases, 2021	11
Operating Leases, 2022	8
Operating Leases, 2023	7
Operating Leases, Thereafter	34
Operating Leases, Total minimum lease payments	93
Operating Leases, Less: amount of lease payments representing interest	33
Operating Leases, Present value of future minimum lease payments	60
Operating Leases, Less: current obligations under leases	(26)
Operating Leases, Long-term lease obligations	34
Finance Leases, 2020	1
Finance Leases, 2021	1
Finance Leases, 2022	1
Finance Leases, Thereafter	110
Finance Leases, Total minimum lease payments	113
Finance Leases, Less: amount of lease payments representing interest	(110)
Finance Leases, Present value of future minimum lease payments	3
Finance Leases, Less: current obligations under leases	(1)
Finance Leases, Long-term lease obligations	$ 3