Note 10 - Income Taxes Income Tax Details (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) percentagepoint	Dec. 31, 2016 USD ($)
Income Tax Disclosure [Abstract]
Accrued Income Taxes, Current	$ 95,600
Income Taxes Receivable, Current	48,400
Operating Loss Carryforwards	124,400
Alternative minimum tax credit carryforward	57,086	$ 7,367
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	6,500
State net operating loss carryforward	69,500
Deferred Tax Assets, Valuation Allowance	$ 65,023	$ 46,892
Percentage of Stock Ownership Needed to Be Included in Calculation of Change in Control Under Section 382 of Internal Revenue Code of 1986	5.00%
Number of Basis Point Increase in Ownership Over Three Year Period Needed By the Entity's Five Percent Shareholders | percentagepoint	50
Number of Years (Rolling) Used for Calculating Percentage Change in Ownership for Change in Control	3 years