Note 15 - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Balance as of January 1	$ 84	$ 85	$ 92
Tax positions related to the current year:
Additions	7		1
Tax positions related to prior years:
Additions	6	1
Reductions	(28)	(2)	(7)
Settlements with taxing jurisdictions	(4)
Lapses in statute of limitations	(4)		(1)
Balance as of December 31	$ 61	$ 84	$ 85