Note 5 - Income Taxes - Changes in the Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Balance at beginning of year	$ (115,806)	$ (32,094)	$ (27,155)
Balance at end of year	(99,602)	(115,806)	(32,094)
Increase Due to Uncertainty of Recovery [Member]
Valuation allowance, deferred tax asset, increase (decrease)	(2,868)	(92,393)	(6,314)
Decrease Related to Utilization and Expiration [Member]
Valuation allowance, deferred tax asset, increase (decrease)	$ 19,072	$ 8,681	$ 1,375