Note 11 - Schedule of Information Related to Lease Expense for Finance and Operating Leases (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Finance lease expense
Amortization of leased assets		$ 1	$ 3
Operating lease expense		21	25
Variable lease expense	[1]	9	10
Total lease expense		$ 31	$ 38

[1] Variable lease expense is related to real estate leases and primarily includes taxes, insurance and operating costs.