Note 7 - Taxes on Income (Details) - Income Tax Rate Reconciliation	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Income Tax Rate Reconciliation [Abstract]
Statutory Federal income tax rate	34.00%	34.00%
State and local income taxes, net of Federal income tax benefit	2.20%	2.30%
Effect of change in unrecognized tax benefit		(2.00%)
Untaxed foreign income	(3.30%)	(6.00%)
Non-deductible share-based employee compensation expense	1.60%	2.30%
Other items	0.80%	0.50%
Effective income tax rate	35.30%	31.10%

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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 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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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 contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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