Accounts Payable Current Accounts payable - trade Accounts Receivable Net Current Accounts receivable, net of allowance for doubtful accounts of $400 at July 31, 2012 and April 30, 2012 Accrued Income Taxes Current Income taxes payable Accrued Liabilities Current Accrued liabilities Accumulated Other Comprehensive Income Loss Net Of Tax Accumulated other comprehensive income Additional Paid In Capital Additional paid-in capital Allowance For Doubtful Accounts Receivable Current Accounts receivable, allowance for doubtful accounts Amendment Flag Amendment Flag Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Number of excluded options and SARS from calculation of diluted earnings per share Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Assets Assets Total assets Assets [Abstract] ASSETS: Assets Current Total current assets Assets Current [Abstract] Current assets: Available For Sale Securities Redeemed available-for-sale securities Available For Sale Securities Amortized Cost Cost Availableforsale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses 2 Unrealized Losses Availableforsale Securities Continuous Unrealized Loss Position Aggregate Losses 2 Unrealized Losses Available For Sale Securities Continuous Unrealized Loss Position Fair Value Fair Value Availableforsale Securities Continuous Unrealized Loss Position Less Than 12 Months Aggregate Losses 2 Unrealized Losses Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value Fair Value Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value Fair Value Available For Sale Securities Current Current Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value Due after five years through ten years Available For Sale Securities Debt Maturities After One Through Five Years Fair Value Due after one year through five years Available For Sale Securities Fair Value Disclosure Fair Market Value Available For Sale Securities Gross Realized Gains Realized gain Availableforsale Securities Gross Unrealized Gain Gross Unrealized Gains Available For Sale Securities Gross Unrealized Losses 1 Gross Unrealized Losses Available For Sale Securities [Text Block] Costs, Gross Unrealized Gains, Gross Unrealized Losses and Fair Market Value of Available-For-Sale Securities B E BELGIUM Billings In Excess Of Cost Billings in excess of costs and estimated earnings Business Acquisition Acquiree [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition Cost Of Acquired Entity Cash Paid Cash payment at acquisition Business Acquisition [Line Items] Business Acquisition [Line Items] Business Acquisition Percentage Of Voting Interests Acquired Percentage of fully owned stock of subsidiary Business Acquisition Pro Forma Earnings Per Share Basic Earnings per share- basic Business Acquisition Pro Forma Earnings Per Share Diluted Earnings per share- diluted Business Acquisition Pro Forma Information [Text Block] Pro Forma Results of Operations Business Acquisition, Pro Forma Operating Income (Loss) Business Acquisition Pro Forma Operating Income Loss Operating profit Business Acquisition Purchase Price Allocatioin Deferred Tax Asset Business Acquisition Purchase Price Allocatioin Deferred Tax Asset Purchase price allocation to deferred taxes Business Acquisition Purchase Price Allocation Goodwill Amount Purchase price allocation to goodwill Business Acquisition, Purchase Price Allocation, Intangible Assets and Goodwill Business Acquisition Purchase Price Allocation Intangible Assets And Goodwill Purchase price allocation to intangible assets including goodwill Business Acquisition Purchase Price Allocation Tangible Assets Purchase price allocation to tangible assets Business Acquisitions Pro Forma Net Income Loss Net income Business Acquisitions Pro Forma Revenue Revenues Business Combination Disclosure [Text Block] ACQUISITION OF ELCOM TECHNOLOGIES, INC. Business Combination Step Acquisition Equity Interest In Acquiree Fair Value Fair value of subsidiary at the date of acquisition Business Combination Step Acquisition Equity Interest In Acquiree Percentage Percentage of capital stock purchased Capital Lease Obligations Noncurrent Capital lease obligation- noncurrent Cash And Cash Equivalents At Carrying Value Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Cash and cash equivalents Cash And Cash Equivalents Period Increase Decrease Net increase in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Before Adjustment Cash And Cash Equivalents Period Increase Decrease Before Adjustment Net increase in cash and cash equivalents before effect of exchange rate changes Cash Paid During Period For [Abstract] Cash Paid During Period For [Abstract] Cash paid during the period for: Cash Surrender Value Of Life Insurance And Cash Held In Trust Cash Surrender Value Of Life Insurance And Cash Held In Trust Cash surrender value of life insurance and cash held in trust Change In Accounting Estimate By Type [Axis] Change in Accounting Estimate by Type [Axis] Change In Accounting Estimate Type [Domain] Change in Accounting Estimate, Type [Domain] Class Of Treasury Stock [Table] Class of Treasury Stock [Table] C N CHINA Commitments And Contingencies Commitments and contingencies Common Stock Par Or Stated Value Per Share Common stock, par value Common Stock Shares Issued Common stock, issued The most subordinated ownership interest in a corporation - Number of Shares Common Stock Shares [Member] Common Stock Shares Common Stock Value Common stock - $1.00 par value, issued 9,163,940 shares Comprehensive Income Net Of Tax Comprehensive income Comprehensive Income Net Of Tax [Abstract] Comprehensive Income Contracts Accounted For Under Percentage Of Completion [Member] Contracts Accounted for under Percentage of Completion Corporate [Member] Corporate Cost and Estimated Earnings on Uncompleted Contracts Cost And Estimated Earnings On Uncompleted Contracts Table [Text Block] Costs and Estimated Earnings in Excess of Billings, Net Cost Method Investment, Ownership Percentage Cost Method Investment Ownership Percentage Cost method investment ownership percentage Cost Of Revenue Cost of revenues Costs In Excess Of Billings On Uncompleted Contracts Or Programs Costs and estimated earnings in excess of billings Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year Costs and estimated earnings in excess of billings, net Net asset Current Fiscal Year End Date Current Fiscal Year End Date Deferred Compensation Liability Classified Noncurrent Deferred compensation Deferred Rent And Other Long Term Liabilities Noncurrent Deferred Rent And Other Long Term Liabilities Noncurrent Deferred rent and other liabilities Deferred Tax Assets Net Current Deferred income taxes Deferred Tax Assets Net Noncurrent Deferred income taxes Deferred Tax Assets Valuation Allowance Remaining deferred tax asset valuation allowance Description Of New Accounting Pronouncements Not Yet Adopted Recently Issued Accounting Pronouncements Disclosure - ACQUISITION OF ELCOM TECHNOLOGIES, INC. - Additional Information [Abstract] Disclosure A C Q U I S I T I O N O F E L C O M T E C H N O L O G I E S I N C Additional Information [Abstract] Disclosure - ACQUISITION OF ELCOM TECHNOLOGIES, INC. - Additional Information [Abstract] Disclosure - Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Market Value of Available-for-Sale Securities [Abstract] Disclosure Cost Gross Unrealized Gains Gross Unrealized Losses And Fair Market Value Of Availablefor Sale Securities [Abstract] Disclosure - Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Market Value of Available-for-Sale Securities [Abstract] Disclosure - Costs and Estimated Earnings in Excess of Billings, Net [Abstract] Disclosure Costs And Estimated Earnings In Excess Of Billings Net [Abstract] Disclosure - Costs and Estimated Earnings in Excess of Billings, Net [Abstract] Disclosure - COSTS AND ESTIMATED EARNINGS IN EXCESS OF BILLINGS, NET - Additional Information [Abstract] Disclosure C O S T S A N D E S T I M A T E D E A R N I N G S I N E X C E S S O F B I L L I N G S N E T Additional Information [Abstract] Disclosure - COSTS AND ESTIMATED EARNINGS IN EXCESS OF BILLINGS, NET - Additional Information [Abstract] Disclosure - EARNINGS PER SHARE - Additional Information [Abstract] Disclosure E A R N I N G S P E R S H A R E Additional Information [Abstract] Disclosure - EARNINGS PER SHARE - Additional Information [Abstract] Disclosure - Fair Value and Unrealized Losses, Aggregated by Investment Type and Length of Time Individual Securities have been in Continuous Unrealized Loss Position [Abstract] Disclosure Fair Value And Unrealized Losses Aggregated By Investment Type And Length Of Time Individual Securities Have Been In Continuous Unrealized Loss Position [Abstract] Disclosure - Fair Value and Unrealized Losses, Aggregated by Investment Type and Length of Time Individual Securities have been in Continuous Unrealized Loss Position [Abstract] Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information [Abstract] Disclosure F A I R V A L U E O F F I N A N C I A L I N S T R U M E N T S Additional Information [Abstract] Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information [Abstract] Disclosure Income Taxes Additional Information [Abstract] Disclosure Income Taxes Additional Information [Abstract] Disclosure Income Taxes Additional Information [Abstract] Disclosure - INVENTORIES - Additional Information [Abstract] Disclosure I N V E N T O R I E S Additional Information [Abstract] Disclosure - INVENTORIES - Additional Information [Abstract] Disclosure - Inventories Reported at Lower of Cost or Market [Abstract] Disclosure Inventories Reported At Lower Of Cost Or Market [Abstract] Disclosure - Inventories Reported at Lower of Cost or Market [Abstract] Disclosure - Investment in Morion Inc - Additional Information [Abstract] Disclosure Investment In Morion Inc Additional Information [Abstract] Disclosure - Investment in Morion Inc - Additional Information [Abstract] Disclosure - Maturities of Fixed Income Securities Classified as Available-for-Sale [Abstract] Disclosure Maturities Of Fixed Income Securities Classified As Availablefor Sale [Abstract] Disclosure - Maturities of Fixed Income Securities Classified as Available-for-Sale [Abstract] Disclosure - Pro Forma Results of Operations [Abstract] Disclosure Pro Forma Results Of Operations [Abstract] Disclosure - Pro Forma Results of Operations [Abstract] Disclosure - Reconciliation of Segment Identifiable Assets to Consolidated Assets [Abstract] Disclosure Reconciliation Of Segment Identifiable Assets To Consolidated Assets [Abstract] Disclosure - Reconciliation of Segment Identifiable Assets to Consolidated Assets [Abstract] Disclosure - Reconciliation of Segment Revenues and Operating Profit (Loss) to Consolidated [Abstract] Disclosure Reconciliation Of Segment Revenues And Operating Profit Loss To Consolidated [Abstract] Disclosure - Reconciliation of Segment Revenues and Operating Profit (Loss) to Consolidated [Abstract] Disclosure - Reconciliation of Weighted Average Shares Outstanding for Basic and Diluted Earnings per Share [Abstract] Disclosure Reconciliation Of Weighted Average Shares Outstanding For Basic And Diluted Earnings Per Share [Abstract] Disclosure - Reconciliation of Weighted Average Shares Outstanding for Basic and Diluted Earnings per Share [Abstract] Disclosure Segment Information Additional Information [Abstract] Disclosure Segment Information Additional Information [Abstract] Disclosure Segment Information Additional Information [Abstract] Disclosure - TREASURY STOCK TRANSACTIONS - Additional Information [Abstract] Disclosure T R E A S U R Y S T O C K T R A N S A C T I O N S Additional Information [Abstract] Disclosure - TREASURY STOCK TRANSACTIONS - Additional Information [Abstract] Document Documentand Entity Information [Abstract] Document Documentand Entity Information [Abstract] Document Documentand Entity Information [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Document Information [Line Items] Document Information [Line Items] Document Period End Date Document Period End Date Document Type Document Type Due From Related Parties Current Due from related party Earnings Per Share [Abstract] Net income per common share: Earnings Per Share Basic Basic Earnings Per Share Diluted Diluted Earnings Per Share [Text Block] EARNINGS PER SHARE Effect Of Exchange Rate On Cash And Cash Equivalents Effect of exchange rate changes on cash and cash equivalents Elcom Technologies Inc [Member] Elcom Technologies Inc [Member] Elcom Eligible Item Or Group For Fair Value Option [Axis] Eligible Item or Group for Fair Value Option [Axis] Entities [Table] Entities [Table] Entity Central Index Key Entity Central Index Key Entity Common Stock Shares Outstanding Entity Common Stock, Shares Outstanding Entity [Domain] Entity [Domain] Entity Filer Category Entity Filer Category Entity Registrant Name Entity Registrant Name Equity Class Of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Equity Securities [Member] Equity Securities Fair Value By Balance Sheet Grouping [Text Block] Maturities of Fixed Income Securities Classified as Available-for-Sale Fair Value Disclosures [Text Block] FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Inputs Control Premium Adjustment for control premium Fair Value Option Eligible Item Or Group [Domain] Fair Value, Option, Eligible Item or Group [Domain] FEI-Elcom [Member] F E I Elcom [Member] FEI-Elcom Financing [Axis] Financing [Axis] Financing [Domain] Financing [Domain] Fixed Income Securities [Member] Fixed Income Securities Fixed Maturities [Member] Fixed Maturities Frequency Electronics Inc New York China [Member] Frequency Electronics Inc New York China [Member] Frequency Electronics Inc New York China Frequency Electronics Inc New York [Member] Frequency Electronics Inc New York [Member] FEI-NY Frequency Electronics Inc Zyfer [Member] Frequency Electronics Inc Zyfer [Member] FEI-Zyfer Gain Loss On Investments Gain on investment of subsidiary Gillam Frequency Electronics Inc [Member] Gillam Frequency Electronics Inc [Member] Gillam-FEI Gross Profit Gross margin Impairment Of Investments Impairment charges of investment Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest Income before provision for income taxes Income Loss From Equity Method Investments Equity income Income Statement [Abstract] Income Statement [Abstract] Income Tax Disclosure [Text Block] INCOME TAXES Income Taxes Paid Income Taxes Income Tax Expense Benefit Provision for income taxes Increase Decrease In Operating Capital Net changes in operating assets and liabilities Intangible Assets Net Including Goodwill Goodwill and other intangible assets Interest Expense Interest expense Interest Income Other Interest income on notes receivable Interest Paid Interest Inter Segment [Member] Inter Segment [Member] Inter Segment Inventory Disclosure [Line Items] Inventory Disclosure [Line Items] Inventory Disclosure [Line Items] Inventory Disclosure [Table] Inventory Disclosure [Table] Inventory Disclosure [Table] Inventory Disclosure [Text Block] INVENTORIES Inventory Finished Goods Finished Goods Inventory Net Inventories Inventories, Net Inventories, net Inventory Raw Materials Raw Materials and Component Parts Inventory Work In Process Work in Progress Investment [Axis] Investment [Axis] Investment [Domain] Investment [Domain] Investment Holdings [Text Block] Investment in Morion, Inc. Investment Income Interest Investment income Investments In Affiliates Subsidiaries Associates And Joint Ventures Investment in affiliates Legal Entity [Axis] Legal Entity [Axis] Liabilities Total liabilities Liabilities And Stockholders Equity Total liabilities and stockholders' equity Liabilities And Stockholders Equity [Abstract] LIABILITIES AND STOCKHOLDERS' EQUITY: Liabilities Current Total current liabilities Liabilities Current [Abstract] Current liabilities: Liabilities For Guarantees On Long Duration Contracts [Line Items] Liabilities for Guarantees on Long-Duration Contracts [Line Items] Liabilities For Guarantees On Long Duration Contracts [Table] Liabilities for Guarantees on Long-Duration Contracts [Table] Long Term Contracts Or Programs Disclosure [Text Block] COSTS AND ESTIMATED EARNINGS IN EXCESS OF BILLINGS, NET Marketable Securities Current Marketable securities Minority Interest Ownership Percentage By Noncontrolling Owners Percentage of minority ownership interest Morion Inc [Member] Morion Inc [Member] Morion Net Cash Provided By Used In Financing Activities Net cash used in financing activities Net Cash Provided By Used In Financing Activities [Abstract] Cash flows from financing activities: Net Cash Provided By Used In Investing Activities Net cash provided by (used in) investing activities Net Cash Provided By Used In Investing Activities [Abstract] Cash flows from investing activities: Net Cash Provided By Used In Operating Activities Net cash (used in) provided by operating activities Net Cash Provided By Used In Operating Activities [Abstract] Cash flows from operating activities: Net Income Loss Net income Net income Nonoperating Income Expense [Abstract] Other income (expense): Number of Principal Markets Number Of Principal Markets Number of principal markets Number Of Reportable Segments Number of reportable segments Operating Income Loss Operating profit (loss) Operating profit Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] CONSOLIDATED FINANCIAL STATEMENTS Other Assets Noncurrent Other assets Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax Foreign currency translation adjustment Other Comprehensive Income Loss Net Of Tax Total other comprehensive (loss) income Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Other comprehensive income (loss): Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax Change in market value of marketable securities Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax Deferred tax effect of change in marketable securities Other Noncash Income Expense Non-cash charges to earnings, net Other Nonoperating Income Expense Other income, net Payments To Acquire Marketable Securities Purchase of marketable securities Payments To Acquire Property Plant And Equipment Purchase of fixed assets Preferred Stock Par Or Stated Value Per Share Preferred stock, par value Preferred Stock Value Preferred stock - $1.00 par value Prepaid Expense And Other Assets Current Prepaid expenses and other Proceeds From Sale And Maturity Of Marketable Securities Proceeds on redemption of marketable securities Proceeds From Stock Options Exercised Proceeds from exercise of stock options Professional Fees Payment for professional fees Property Plant And Equipment Net Property, plant and equipment, at cost, less accumulated depreciation and amortization Receivable Transfer to Investment Receivable Transfer To Investment Forgiven receivable transferred to investment Reconciliation Of Assets From Segment To Consolidated [Table] Reconciliation of Assets from Segment to Consolidated [Table] Reconciliation Of Assets From Segment To Consolidated [Text Block] Reconciliation of Segment Identifiable Assets to Consolidated Assets Reconciliation Of Operating Profit Loss From Segments To Consolidated [Table] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table] Reconciliation Of Operating Profit Loss From Segments To Consolidated [Text Block] Reconciliation of Segment Operating Profit to Consolidated Operating Profit Redeemed Securities [Member] Redeemed Securities [Member] Redeemed Available-for-Sale Securities Related Party [Domain] Related Party [Domain] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Related Party Transaction Purchases From Related Party Purchases from related party Related Party Transactions By Related Party [Axis] Related Party [Axis] Repayments Of Long Term Capital Lease Obligations Payment of lease obligations Research And Development Expense Research and development expense Retained Earnings Accumulated Deficit Retained earnings Revenue From Related Parties Revenue from related party Revenues Net revenues Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule Of Available For Sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Schedule Of Available For Sale Securities [Table] Schedule of Available-for-sale Securities [Table] Schedule Of Business Acquisitions By Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Schedule Of Earnings Per Share Reconciliation Table [Text Block] Reconciliation of Weighted Average Shares Outstanding for Basic and Diluted Earnings per Share Schedule Of Inventory Current Table [Text Block] Inventories Reported at Lower of Cost or Market Schedule Of Related Party Transactions By Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Weighted Average Number of Shares Outstanding [Table] Schedule Of Weighted Average Number Of Shares Outstanding [Table] Schedule of Weighted Average Number of Shares Outstanding [Table] Segment [Domain] Segment [Domain] Segment Reporting Asset Reconciling Item [Line Items] Segment Reporting, Asset Reconciling Item [Line Items] Segment Reporting Disclosure [Text Block] SEGMENT INFORMATION Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items] Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] Selling General And Administrative Expense Selling and administrative expenses Settlement Of Debt [Member] Settlement of Debt Short Term Borrowings Short-term credit obligations Statement Business Segments [Axis] Business Segments [Axis] Statement [Line Items] Statement [Line Items] Statement Of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Statement Of Financial Position [Abstract] Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Stockholders Equity Total stockholders' equity Stockholders Equity [Abstract] Stockholders' equity: Stockholders Equity Before Treasury Stock Stockholders' Equity before Treasury Stock, Total Stock Issued During Period, Shares, 401(k) Contribution Stock Issued During Period Shares Four Zero One K Contribution Shares of common stock held in treasury Stock Issued During Period Shares Treasury Stock Reissued Shares issued from treasury upon the exercise of stock options and SARs Supplemental Cash Flow Information [Abstract] Supplemental disclosures of cash flow information: Text Block [Abstract] Text Block [Abstract] Trading Symbol Trading Symbol Treasury Stock Shares Common stock reacquired and held in treasury, shares Treasury Stock [Text Block] TREASURY STOCK TRANSACTIONS Treasury Stock Value Common stock reacquired and held in treasury - at cost (771,639 shares at July 31, 2012 and 800,787 shares at April 30, 2012) Unrealized Gain Loss On Investments Table [Text Block] Fair Value and Unrealized Losses, Aggregated by Investment Type and Length of Time Individual Securities have been in Continuous Unrealized Loss Position U S UNITED STATES Valuation Allowance [Line Items] Valuation Allowance [Line Items] Valuation Allowance [Table] Valuation Allowance [Table] Weighted Average Number Diluted Shares Outstanding Adjustment Effect of Dilutive Securities Weighted Average Number Of Diluted Shares Outstanding Diluted Diluted EPS Shares outstanding Weighted Average Number Of Shares Outstanding Basic Basic Basic EPS Shares outstanding (weighted average) Weighted Average Number Of Shares Outstanding Diluted Disclosure Items [Abstract] Average shares outstanding: Weighted Average Number of Shares Outstanding [Line Items] Weighted Average Number Of Shares Outstanding [Line Items] Weighted Average Number of Shares Outstanding [Line Items]