Document And Entity Information
Note To Financial Statement Details Textual
statementnote4netincomepersharetables
statementnote5marketablesecuritiestables
statementnote6inventoriestables
statementnote4componentsofcommonsharesoutstandingdetails
statementnote5fairvalueofmarketablesecuritiesdetails
Marketable securities, long term
statementnote5reconciliationofmarketablesecuritiesdetails
Amendment Flag
statementnote5grossunrealizedlossesandfairvalueofinvestmentsdetails
statementnote6inventoriesdetails
Notes To Financial Statements
Income Tax Disclosure [Text Block]
Notes To Financial Statements [Abstract]
us-gaap_AllocatedShareBasedCompensationExpense
Allocated Share-based Compensation Expense
us-gaap_PaymentsForRepurchaseOfCommonStock
Repurchase of common stock
us-gaap_IncreaseDecreaseInDeferredRevenue
Deferred revenue
Maximum [Member]
Range [Axis]
Range [Domain]
Document Fiscal Year Focus
Document Fiscal Period Focus
Net income
Net income
Proceeds from sale of common stock
nvec_SeverityOfUnrealizedLossPercentageOfAdjustedCost
Severity of Unrealized Loss, Percentage of Adjusted Cost
Represents information about the corporate bonds' severity of unrealized loss as a percentage of adjusted cost.
nvec_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue
91,756,557
Fair value of available-for-sale debt securities maturing after three through five years.
us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
Accounts payable and accrued expenses
Document Period End Date
Fair Value Disclosures [Text Block]
Current Fiscal Year End Date
Marketable securities, short term
Award Type [Axis]
Entity Current Reporting Status
Entity Voluntary Filers
Entity Filer Category
Document Type
Statement of Comprehensive Income [Abstract]
Equity Award [Domain]
Stock Repurchase Plan Disclosure [Text Block]
The entire disclosure for the stock repurchase plan.
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]
nvec_NumberOfCorporateBondsResultedInLoss
Number of Corporate Bonds Resulted in Loss
The number of corporate bonds which resulted in a loss.
nvec_NumberOfCorporateBonds
Number of Corporate Bonds
Total number of the entity's portfolio bonds.
us-gaap_AvailableForSaleSecuritiesDebtSecurities
Available-for-sale Securities, Debt Securities
nvec_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughThreeYearsFairValue
91,756,557
Fair value of available-for-sale debt securities maturing in one to three years.
Entity Well-known Seasoned Issuer
INVESTING ACTIVITIES
Weighted average shares outstanding
Prepaid expenses and other assets
Dilutive effect of stock options (in shares)
Accounts receivable, net of allowance for uncollectible accounts of $15,000
Allowance for uncollectible accounts
Statement [Table]
Cash and cash equivalents
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
Research and development
Current assets
us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
(Decrease) increase in cash and cash equivalents
Income Statement [Abstract]
us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations
Net cash (used in) provided by financing activities
us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
Net cash used in investing activities
us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
Net cash provided by operating activities
Excess tax benefits
us-gaap_StockholdersEquity
Total shareholders’ equity
us-gaap_PaymentsOfDividendsCommonStock
Payment of dividends to shareholders
us-gaap_TableTextBlock
Notes Tables
Selling, general, and administrative
us-gaap_StockRepurchaseProgramAuthorizedAmount1
Stock Repurchase Program, Authorized Amount
us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
Stock Repurchase Program, Remaining Authorized Repurchase Amount
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]
Inventories
Total inventories
us-gaap_TreasuryStockSharesAcquired
Treasury Stock, Shares, Acquired
us-gaap_Revenues
Total revenue
Common stock, shares outstanding (in shares)
us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue
91,756,557
Expenses
Unrealized loss from marketable securities, net of tax
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Fair market value, less than 12 months
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue
Total Fair Market Value
Cash dividends declared per common share (in dollars per share)
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchases of fixed assets
us-gaap_Assets
Total assets
us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year
Additional paid-in capital
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss
Total Gross Unrealized Losses
Shareholders’ equity
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses
Gross unrealized losses, less than 12 months
Current liabilities
Entity Registrant Name
us-gaap_PropertyPlantAndEquipmentNet
Net fixed assets
Entity Central Index Key
us-gaap_PaymentsToAcquireMarketableSecurities
Purchases of marketable securities
us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation and amortization
Leasehold improvements
Entity Common Stock, Shares Outstanding (in shares)
Machinery and equipment
Earnings Per Share [Text Block]
nvec_StockRepurchaseProgramAuthorizedAdditionalAmount
Stock Repurchase Program Authorized Additional Amount
Amount of additional stock repurchase plan authorized.
Fixed assets
Non-employee Director Stock Options [Member]
An arrangement whereby a non-employee director is issued automatic stock options on their election or reelection to the company's Board.
Deferred tax assets
Trading Symbol
Scenario [Axis]
Scenario, Unspecified [Domain]
nvec_NumberOfOtherThanTemporarilyImpairedMarketableSecurities
Number of Other-than-temporarily Impaired Marketable Securities
Represents the number of marketable securities the company considers other-than-temporarily impaired.
us-gaap_AssetsCurrent
Total current assets
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
Deferred income taxes
us-gaap_LiabilitiesCurrent
Total current liabilities
Adjustments to reconcile net income to net cash provided by operating activities:
Changes in operating assets and liabilities:
Supplemental disclosures of cash flow information:
Depreciation and amortization
Fair Value, Inputs, Level 1 [Member]
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and shareholders’ equity
Fair Value Hierarchy [Domain]
Fair Value, Inputs, Level 2 [Member]
Accumulated other comprehensive income
Fair Value, Hierarchy [Axis]
Retained earnings
Contract research and development
Deferred revenue
Proceeds from maturities and sales of marketable securities
Subsequent Event Type [Domain]
Subsequent Event Type [Axis]
Statement of Financial Position [Abstract]
us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities
Excess tax benefits
Quarterly Financial Information [Text Block]
Stock-based compensation
Subsequent Event [Member]
Earliest Tax Year [Member]
Statement of Cash Flows [Abstract]
Latest Tax Year [Member]
us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
Comprehensive income
us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued
Unrecognized Tax Benefits, Interest on Income Taxes Accrued
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]
OPERATING ACTIVITIES
Marketable Securities [Table Text Block]
FINANCING ACTIVITIES
Business Description and Basis of Presentation [Text Block]
us-gaap_OpenTaxYear
Open Tax Year
Product sales
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses
Gross unrealized losses, greater than 12 months
us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits
Long-term deferred tax assets
Dividends [Text Block]
Disclosure about dividends which has been declared and to be paid during the period.
Cash paid during the period for income taxes
Net income per share – diluted (in dollars per share)
us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Diluted (in shares)
Shares used in computing net income per share – diluted (in shares)
us-gaap_IncreaseDecreaseInInventories
Inventories
Accrued payroll and other
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Income before taxes
Accounts payable
Provision for income taxes
Basic (in shares)
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross Unrealized Gains
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Gross Unrealized Losses
us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Adjusted Cost
Net income per share – basic (in dollars per share)
Tax Period [Domain]
Tax Period [Axis]
Common stock, $0.01 par value, 6,000,000 shares authorized; 4,844,845 issued and outstanding as of December 31, 2015 and 4,857,953 issued and outstanding as of March 31, 2015
Investment Type [Axis]
Class of Stock [Axis]
Common stock, shares issued (in shares)
Accounting Policies [Abstract]
Common stock, shares authorized (in shares)
Schedule of Weighted Average Number of Shares [Table Text Block]
Common stock, par value (in dollars per share)
us-gaap_IncreaseDecreaseInAccountsReceivable
Accounts receivable
Revenue
Municipal Bonds [Member]
Schedule of Inventory, Current [Table Text Block]
Investments [Domain]
Inventory Disclosure [Text Block]
Work in process
Finished goods
us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets
Prepaid expenses and other assets
us-gaap_OperatingExpenses
Total expenses
Statement [Line Items]
Raw materials
Schedule of Unrealized Loss on Investments [Table Text Block]
us-gaap_GrossProfit
Gross profit
Cost of sales
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]
Long-term deferred tax liabilities
us-gaap_DividendsPayableAmountPerShare
Dividends Payable, Amount Per Share
Equity Component [Domain]
Equity Components [Axis]
us-gaap_PolicyTextBlockAbstract
Accounting Policies
Corporate Bond Securities [Member]
us-gaap_OperatingIncomeLoss
Income from operations
Interest income