Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
Income Taxes [Abstract]
Vacation accrual	$ 114,217	$ 137,052
Inventory reserve	65,394us-gaap_DeferredTaxAssetsInventory	107,173us-gaap_DeferredTaxAssetsInventory
Depreciation	(63,631)nvec_DeferredTaxAssetsDepreciation	(37,131)nvec_DeferredTaxAssetsDepreciation
Stock-based compensation deductions	107,570	120,009
Unrealized gain on marketable securities	(425,922)	(500,904)
Other	28,716us-gaap_DeferredTaxAssetsOther	56,588us-gaap_DeferredTaxAssetsOther
Net deferred tax liabilities	(173,656)us-gaap_DeferredTaxAssetsLiabilitiesNet	(117,213)us-gaap_DeferredTaxAssetsLiabilitiesNet
Deferred tax assets	102,052	237,387
Long-term deferred tax liabilities	$ (275,708)	$ (354,600)

Deferred Tax Assets, Depreciation

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax liability attributable to taxable temporary differences, net of deferred tax asset attributable to deductible temporary differences and carryforwards net of valuation allowances expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

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