Note 10 - Long-term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Long-term debt	$ 120	$ 120
Long-term debt, noncurrent	$ 120	120
Unsecured Term Note Payable [Member]
Long-term debt maturity	2018
Long-term debt	$ 10	10
Long-term debt, interest rate	3.60%
Revolving Credit Facility [Member]
Long-term debt maturity	2020
Long-term debt	$ 110	$ 110
Long-term debt, interest rate	2.60%