Note 11 - Income Taxes (Details) - Income Tax Rate Reconciliation	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Rate Reconciliation [Abstract]
U.S. statutory federal tax rate	34.00%	34.00%	34.00%
Settlement with tax authorities	6.20%
Foreign income at lower rates	(43.10%)	(27.70%)	(33.80%)
Changes in valuation allowance	17.60%	5.90%	16.80%
Stock-based compensation		(9.30%)	(13.70%)
Reserves and other	2.50%	(0.40%)	1.30%
Effective tax rate	17.20%	2.50%	4.60%

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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 expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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