Note 16 - Income Taxes - Effective Tax Rate Reconciliation (Details)	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Statutory federal income tax rate	35.00%	35.00%	35.00%
State taxes, net of federal tax benefit	1.00%	1.00%	1.00%
Expense (benefit) of lower-tax foreign jurisdictions	(17.00%)	(10.00%)	(15.00%)
Tax credits	(2.00%)	(3.00%)	(1.00%)
Valuation allowances	4.00%	3.00%
Permanent items		(5.00%)
Tax reserves	1.00%
Tax asset write-off	2.00%	10.00%
Foreign income	2.00%	6.00%	2.00%
Effective tax provision rate	26.00%	37.00%	22.00%

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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 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 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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