Note 5 - Income Taxes - Reconciliation of Statutory Federal Income Tax Rate to Annual Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Computed “statutory” benefit (provision), Amount	$ (33,941)	$ 10,731	$ (4,405)
Computed “statutory” benefit (provision), Percentage	35.00%	35.00%	35.00%
Percentage depletion, Amount	$ 8,114	$ 2,432	$ 6,034
Percentage depletion, Percentage	(8.00%)	8.00%	(48.00%)
Change in valuation allowance, Amount	$ 11,336	$ (84,951)	$ (6,314)
Change in valuation allowance, Percentage	(12.00%)	(277.00%)	50.00%
State taxes, net of federal taxes, Amount	$ (565)	$ (3,639)	$ 1,671
State taxes, net of federal taxes, Percentage	1.00%	(12.00%)	(13.00%)
Foreign currency remeasurement of monetary assets and liabilities, Amount	$ (4,598)	$ 28,184	$ 16,368
Foreign currency remeasurement of monetary assets and liabilities, Percentage	5.00%	92.00%	(130.00%)
Rate differential on foreign earnings, Amount	$ (6,853)	$ (4,746)	$ (5,938)
Rate differential on foreign earnings, Percentage	7.00%	(15.00%)	47.00%
Compensation, Amount	$ (1,311)	$ (815)	$ (1,308)
Compensation, Percentage	1.00%	(3.00%)	10.00%
Other, Amount	$ 390	$ (3,506)	$ (868)
Other, Percentage	(1.00%)	(12.00%)	7.00%
Total income tax benefit (provision)	$ (27,428)	$ (56,310)	$ 5,240
Total	28.00%	(184.00%)	(42.00%)

The remeasurement of cash balances of assets and liabilities from foreign currencies to USD.

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Income tax rate reconciliation foreign currency translation percentage.

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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 domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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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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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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