Note 11 - 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	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating Leases, 2020	$ 21
Operating Leases, 2021	15
Operating Leases, 2022	17
Operating Leases, 2023	9
Operating Leases, 2024	8
Operating Leases, Thereafter	28
Operating Leases, Total minimum lease payments	98
Operating Leases, Less: amount of lease payments representing interest	(38)
Operating Leases, Present value of future minimum lease payments	60
Operating Leases, Less: current obligations under leases	12
Operating Leases, Long-term lease obligations	48
Finance Leases, 2020	1
Finance Leases, 2021	1
Finance Leases, 2022	1
Finance Leases, Thereafter	117
Finance Leases, Total minimum lease payments	120
Finance Leases, Less: amount of lease payments representing interest	(115)
Finance Leases, Present value of future minimum lease payments	5
Finance Leases, Less: current obligations under leases	1
Finance Leases, Long-term lease obligations	$ 4