Note 5 - Income Taxes (Details) - Reconciliation of Statutory Federal Income Tax Rate to Annual Tax Provision (Benefit) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Statutory Federal Income Tax Rate to Annual Tax Provision (Benefit) [Abstract]
Computed “statutory” benefit (provision)	$ (4,405)	$ 12,224	$ (8,342)
Computed “statutory” benefit (provision)	35.00%	35.00%	35.00%
Percentage depletion	6,034	3,946	5,575
Percentage depletion	(48.00%)	11.00%	(24.00%)
Change in valuation allowance other than utilization	(6,314)	(3,870)	(3,837)
Change in valuation allowance other than utilization	50.00%	(11.00%)	16.00%
State taxes, net of federal taxes	1,671	720	(1,110)
State taxes, net of federal taxes	(13.00%)	2.00%	5.00%
Transaction costs		(1,743)
Transaction costs		(5.00%)
Foreign currency translation of monetary assets	16,368	3,445
Foreign currency translation of monetary assets	(130.00%)	10.00%
Rate differential on foreign earnings	(5,938)	(4,255)	(780)
Rate differential on foreign earnings	47.00%	(12.00%)	3.00%
Compensation	(1,308)	(326)	(444)
Compensation	10.00%	(1.00%)	2.00%
Other	(868)	(346)	59
Other	7.00%	(1.00%)
	$ 5,240us-gaap_IncomeTaxExpenseBenefit	$ 9,795us-gaap_IncomeTaxExpenseBenefit	$ (8,879)us-gaap_IncomeTaxExpenseBenefit
	(42.00%)	28.00%	37.00%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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