Document And Entity Information
Dividend yield
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate
Fair Value of Financial Instruments, Policy [Policy Text Block]
Note To Financial Statement Details Textual
Significant Accounting Policies
Share-Based Payment Arrangement, Option, Exercise Price Range [Table Text Block]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
2023
nvec_IncomeTaxReconciliationDeductionForeignDerivedIntangibleIncome
Foreign-derived intangible income deduction
Amount 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 deduction for foreign-derived intangible income.
Note 2 - Summary of Significant Accounting Policies
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo
2024
Tax expense at U.S. Statutory rate
Note 3 - Fair Value of Financial Instruments
Risk-free interest rate
Note 4 - Inventories
Less than 1 year
Note 5 - Stock-based Compensation
Note 6 - Income Taxes
Note 7 - Leases
Note 8 - Concentrations
Note 2 - Summary of Significant Accounting Policies - Weighted Average Number of Shares (Details)
Income Tax Disclosure [Text Block]
Note 3 - Fair Value of Financial Instruments - Fair Value of Available-for-sale Securities (Details)
Unrealized gain (loss) from marketable securities, net of tax
Note 3 - Fair Value of Financial Instruments - Assets Measured on Recurring Basis (Details)
Note 3 - Fair Value of Financial Instruments - Reconciliation of Available-for-sale Securities (Details)
Lessee, Operating Lease, Liability, Maturity [Table Text Block]
us-gaap_ShareBasedCompensation
Stock-based compensation
Expected volatility
Note 3 - Fair Value of Financial Instruments - Investment Securities With Unrealized Losses (Details)
us-gaap_LiabilitiesCurrent
Total current liabilities
Note 4 - Inventories - Summary of Inventories (Details)
Note 5 - Stock-based Compensation - Schedule of Valuation Assumptions (Details)
Note 5 - Stock-based Compensation - Summary of Options Outstanding (Details)
Note 5 - Stock-based Compensation - Summary of Stock Options (Details)
Expected life (years) (Year)
Note 6 - Income Taxes - Schedule of Income Tax Provisions (Details)
Earnings Per Share, Policy [Policy Text Block]
Note 6 - Income Taxes - Reconciliation of Income Tax Provisions (Details)
Note 6 - Income Taxes - Deferred Tax Assets and Liabilities (Details)
Note 7 - Leases - Operating Lease (Details)
Note 7 - Leases - Maturities of Lease Liabilities (Details)
Note 8 - Concentrations - Revenue by Major Customers (Details)
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Notes To Financial Statements
Notes To Financial Statements [Abstract]
nvec_AvailableForSaleDebtSecuritiesRemainingMaturity
Available for Sale Debt Securities, Remaining Maturity (Week)
The remaining maturity of available for sale debt securities.
Income Tax, Policy [Policy Text Block]
nvec_AvailableForSaleDebtSecurititesPercentOfTotalAssets
Available for Sale Debt Securitites, Percent of Total Assets
The amount of available for sale debt securities as a percentage of total assets.
Share-Based Payment Arrangement, Activity [Table Text Block]
us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Gross unrealized losses, 12 months or greater
Proceeds from maturities and sales of marketable securities
us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
Total gross unrealized losses
Research and Development Expense, Policy [Policy Text Block]
us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Gross unrealized losses, less than 12 months
Marketable securities, long-term
Depreciation and amortization
us-gaap_AssetsCurrent
Total current assets
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year)
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value
Share-Based Payment Arrangement [Policy Text Block]
Total fair market value
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number (in shares)
Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block]
Fair market value, less than 12 months
Fair market value, 12 months or greater
Common stock, $0.01 par value, 6,000,000 shares authorized; 4,830,826 issued and outstanding as of March 31, 2022 and 4,833,232 as of March 31, 2021
us-gaap_PaymentsToAcquireMarketableSecurities
Purchases of marketable securities
Adjustments to reconcile net income to net cash provided by operating activities:
Measurement Frequency [Axis]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Weighted average option exercise price (in dollars per share)
Weighted average option exercise price (in dollars per share)
Measurement Frequency [Domain]
Fair Value, Recurring [Member]
Common stock, shares authorized (in shares)
us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice
Terminated, weighted average option exercise price (in dollars per share)
Common stock, shares issued (in shares)
Discount rate
Common stock, par value (in dollars per share)
us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
Granted, weighted average option exercise price (in dollars per share)
Revenue from Contract with Customer [Policy Text Block]
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_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice
Exercised, weighted average option exercise price (in dollars per share)
Standard Product Warranty, Policy [Policy Text Block]
Accrued payroll and other
Statistical Measurement [Domain]
Operating cash flows for leases
Maximum [Member]
Lessee, Operating Leases [Text Block]
Minimum [Member]
Accounts payable
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Option shares reserved (in shares)
Product and Service [Axis]
Product and Service [Domain]
us-gaap_DeferredTaxAssetsNet
Deferred tax assets
Statistical Measurement [Axis]
us-gaap_PolicyTextBlockAbstract
Accounting Policies
Cash paid during the year for income taxes
us-gaap_DeferredTaxAssetsOther
Other
Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]
Inventories
Total inventories
us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Revenue
Unrealized gain on marketable securities, asset
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchases of fixed assets
Dilutive effect of stock options (in shares)
Fair Value Hierarchy and NAV [Domain]
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)
Customer [Axis]
Inventory reserve
Customer [Domain]
Fair Value, Inputs, Level 1 [Member]
Fair Value, Inputs, Level 2 [Member]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)
Weighted average shares outstanding
Fair Value Hierarchy and NAV [Axis]
Current liabilities
Product [Member]
us-gaap_Assets
Total assets
Supplemental disclosures of cash flow information:
Cumulative Effect, Period of Adoption [Domain]
Cumulative Effect, Period of Adoption [Axis]
us-gaap_PropertyPlantAndEquipmentUsefulLife
Property, Plant and Equipment, Useful Life (Year)
Cumulative Effect, Period of Adoption, Adjustment [Member]
Fixed assets
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total
OPERATING ACTIVITIES
us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions
Share-Based Payment Arrangement, Exercise of Option, Tax Benefit
Statement [Line Items]
Allowance for uncollectible accounts
Paid time off accrual
Accounts receivable, net of allowance for uncollectible accounts of $15,000
us-gaap_NumberOfReportableSegments
Number of Reportable Segments
Stock-based compensation deductions
Deferred tax assets
Share-Based Payment Arrangement [Text Block]
Marketable securities, short-term
Additional paid-in capital
AOCI Attributable to Parent [Member]
Leasehold Improvements [Member]
Property, Plant and Equipment, Policy [Policy Text Block]
Long-Lived Tangible Asset [Axis]
Stock Repurchase Plan Disclosure [Text Block]
The entire disclosure for the stock repurchase plan.
Long-Lived Tangible Asset [Domain]
Business Description and Basis of Presentation [Text Block]
Award Type [Domain]
Current assets
Fair Value Disclosures [Text Block]
Basis of Presentation and Significant Accounting Policies [Text Block]
Award Type [Axis]
Net income
Net income
1-3 years
Fair value of available-for-sale debt securities maturing in one to three years.
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Cash and cash equivalents at beginning of year
Cash and cash equivalents at end of year
Inventory, Policy [Policy Text Block]
Interest income
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
Increase in cash and cash equivalents
us-gaap_Liabilities
Total liabilities
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash used in financing activities
us-gaap_OperatingIncomeLoss
Income from operations
Share-Based Payment Arrangement, Option [Member]
us-gaap_NetCashProvidedByUsedInOperatingActivities
Net cash provided by operating activities
Prepaid expenses and other assets
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash provided by investing activities
Cost of sales
us-gaap_GrossProfit
Gross profit
3-5 years
Fair value of available-for-sale debt securities maturing after three through five years.
Shareholders’ equity
Less accumulated depreciation and amortization
us-gaap_PropertyPlantAndEquipmentNet
Net fixed assets
us-gaap_PropertyPlantAndEquipmentGross
Property, Plant and Equipment, Gross, Ending Balance
Machinery and equipment
Leasehold improvements
us-gaap_DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities
Unrealized gain on marketable securities, liability
us-gaap_PaymentsOfDividendsCommonStock
Payment of dividends to shareholders
Total comprehensive income
INVESTING ACTIVITIES
us-gaap_PaymentsForRepurchaseOfCommonStock
Repurchase of common stock
Total
Estimated Fair Value
Retained Earnings [Member]
State, Current taxes
State, Deferred taxes
us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
Stock Repurchase Program, Remaining Authorized Repurchase Amount
Accounts payable and accrued expenses
Additional Paid-in Capital [Member]
Share Repurchase Program [Domain]
Common Stock [Member]
Federal, Current taxes
us-gaap_StockRepurchaseProgramAuthorizedAmount1
Stock Repurchase Program, Authorized Amount
Federal, Deferred taxes
Provision for income taxes
Income tax provision
Equity Components [Axis]
Share Repurchase Program [Axis]
Equity Component [Domain]
Revenue
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income before taxes
nvec_ProductWarrantyTerm
Product Warranty Term (Year)
Represents product warranty term.
us-gaap_OperatingExpenses
Total expenses
us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent
us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay
nvec_SharebasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodFairValue
Share-based Compensation Arrangement by Share Based Payment Award Options Grants in Period Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value
Cash and cash equivalents
Range One [Member]
The first range of exercise prices.
Range Two [Member]
The second range of exercise prices
us-gaap_AllocatedShareBasedCompensationExpense
Share-Based Payment Arrangement, Expense
Option Shares Reserved [Member]
Award type option shares reserved.
nvec_DeferredTaxAssetsDepreciation
Depreciation and amortization
Deferred Tax Assets, Depreciation
Document Annual Report
Machinery and Equipment [Member]
us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit
us-gaap_DefinedBenefitPlanContributionsByEmployer
Defined Benefit Plan, Plan Assets, Contributions by Employer
nvec_StockRepurchaseProgramAuthorizedAdditionalAmount
Stock Repurchase Program Authorized Additional Amount
Amount of additional stock repurchase plan authorized.
Customer B [Member]
Related to customer designated as B
Customer A [Member]
Related to customer designated as A
Cash and Cash Equivalents, Policy [Policy Text Block]
Receivable [Policy Text Block]
Amendment Flag
Entity Incorporation, State or Country Code
us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits, Ending Balance
Accounting Policies [Abstract]
us-gaap_OpenTaxYear
Open Tax Year
us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income
Document Transition Report
City Area Code
Use of Estimates, Policy [Policy Text Block]
New Accounting Pronouncements, Policy [Policy Text Block]
Concentration Risk Disclosure [Text Block]
Entity Interactive Data Current
Cash dividends declared per common share (in dollars per share)
Common Stock, Dividends, Per Share, Declared (in dollars per share)
Common stock per share (in dollars per share)
us-gaap_SharesOutstanding
Balance (in shares)
Balance (in shares)
Security Exchange Name
Common stock, shares outstanding (in shares)
Title of 12(b) Security
us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued
Unrecognized Tax Benefits, Interest on Income Taxes Accrued
Current Fiscal Year End Date
Variable lease cost
us-gaap_LeaseCost
Total
us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets
Prepaid expenses and other assets
nvec_NumberOfOtherThanTemporarilyImpairedAvailableForsaleSecurities
Number of Other-than-temporarily Impaired Available-for-sale Securities
Represents number of other-than-temporarily impaired available-for-sale securities.
Document Fiscal Period Focus
Operating lease cost
Document Fiscal Year Focus
Lease, Cost [Table Text Block]
Document Period End Date
Entity File Number
Entity Emerging Growth Company
Concentration Of Risk and Financial Instruments Policy [Policy Text Block]
The policy disclosure of the concentration of risk and financial instrument.
Document Type
Entity Small Business
Entity Shell Company
us-gaap_DividendsCommonStockCash
Cash dividends declared ($4.00 per share of common stock)
Document Information [Line Items]
Document Information [Table]
Entity Public Float
Entity Filer Category
Entity Current Reporting Status
Entity Voluntary Filers
Entity Well-known Seasoned Issuer
us-gaap_ImpairmentOfLongLivedAssetsHeldForUse
Impairment, Long-Lived Asset, Held-for-Use, Total
Diluted (in shares)
Shares used in computing net income per share – diluted (in shares)
Percentage of concentration
Concentration Risk, Percentage
us-gaap_IncreaseDecreaseInAccountsReceivable
Accounts receivable
Stock-based compensation
Statement of Comprehensive Income [Abstract]
Entity Tax Identification Number
Entity Central Index Key
us-gaap_DepreciationAndAmortization
Depreciation, Depletion and Amortization, Nonproduction, Total
Entity Registrant Name
Entity [Domain]
Customer Concentration Risk [Member]
Legal Entity [Axis]
Statement [Table]
Entity Address, Address Line One
Statement of Financial Position [Abstract]
Net income per share – diluted (in dollars per share)
Basic (in shares)
Entity Address, City or Town
Entity Address, Postal Zip Code
Net income per share – basic (in dollars per share)
Entity Address, State or Province
Concentration Risk Type [Axis]
Concentration Risk Type [Domain]
us-gaap_StockRepurchasedDuringPeriodShares
Stock Repurchased During Period, Shares (in shares)
Statement of Cash Flows [Abstract]
Entity Common Stock, Shares Outstanding
Statement of Stockholders' Equity [Abstract]
us-gaap_StockRepurchasedAndRetiredDuringPeriodValue
Repurchase of common stock
us-gaap_StockRepurchasedAndRetiredDuringPeriodShares
Repurchase of common stock (in shares)
Income Statement [Abstract]
Revenue Benchmark [Member]
Remaining lease term (years) (Month)
Accounts Receivable [Member]
Investments [Domain]
us-gaap_IncreaseDecreaseInInventories
Inventories
Trading Symbol
Concentration Risk Benchmark [Axis]
Concentration Risk Benchmark [Domain]
Investment Type [Axis]
Investments Classified by Contractual Maturity Date [Table Text Block]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]
Local Phone Number
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Exercise of stock options (in shares)
Exercised (in shares)
Exercised (in shares)
us-gaap_TableTextBlock
Notes Tables
Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]
Exercise of stock options
Selling, general, and administrative
us-gaap_ProvisionForDoubtfulAccounts
Accounts Receivable, Credit Loss Expense (Reversal)
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
Contract Research and Development [Member]
Represents the information pertaining to the contract research and development.
us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Dividends Payable, Date to be Paid
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Granted (in shares)
Granted (in shares)
FINANCING ACTIVITIES
Other
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod
Terminated (in shares)
Terminated (in shares)
us-gaap_DividendsPayableDateOfRecordDayMonthAndYear
Dividends Payable, Date of Record
Raw materials
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and shareholders’ equity
Corporate Bond Securities [Member]
Finished goods
Repurchase Program 2009 [Member]
Information pertaining to the 2009 Repurchase Program.
Work in process
Retained earnings
Research and development
Accumulated other comprehensive income (loss)
Expenses
Money Market Funds [Member]
Changes in operating assets and liabilities:
us-gaap_StockholdersEquity
Total shareholders’ equity
Balance
Balance
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
Inventory Disclosure [Text Block]
Subsequent Event [Member]
us-gaap_OperatingLeaseLiabilityNoncurrent
Operating lease
Schedule of Inventory, Current [Table Text Block]
Class of Stock [Axis]
Total lease liabilities
Subsequent Event Type [Axis]
Operating lease
Subsequent Event Type [Domain]
Weighted average exercise price (in dollars per share)
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Gross Unrealized Holding Losses
Customer A and B [Member]
Represents the information pertaining to Customer A and B.
Retirement Benefits [Text Block]
Weighted average contractual life (Year)
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross Unrealized Holding Gains
Subsequent Events [Text Block]
Schedule of Weighted Average Number of Shares [Table Text Block]
Range of exercise prices, upper limit (in dollars per share)
Right-of-use asset – operating lease
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Total lease payments
us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
Imputed lease interest
Number outstanding (in shares)
Deferred income taxes
us-gaap_DeferredIncomeTaxExpenseBenefit
Amortized Cost
Exercise Price Range [Axis]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree
2025
State income taxes, net of Federal benefit
Exercise Price Range [Domain]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour
2026
Range of exercise prices, lower limit (in dollars per share)
us-gaap_IncomeTaxReconciliationTaxCreditsResearch
Research and development credits
Auditor Name
Auditor Location
Auditor Firm ID