Document and Entity Information [Abstract] Statement [Table] Class of Stock [Axis] Class of Stock [Domain] Common Class A [Member] Class A Common Stock Class A common stock [Member] Common Class B [Member] Class B Common Stock Class B common stock [Member] Statement [Line Items] Entity Registrant Name Entity Central Index Key Trading Symbol Amendment Flag Current Fiscal Year End Date Document Type Document Period End Date Document Fiscal Period Focus Document Fiscal Year Focus Entity Filer Category Entity Common Stock, Shares Outstanding Balance Sheets [Abstract] Common Stock To Be Issued [Member] Common Stock To Be Issued Common stock to be issued. Assets [Abstract] Assets Assets, Current [Abstract] Current assets: Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Accounts Receivable, Net, Current Trade accounts receivable, net of allowance for doubtful accounts of $19 and $19, respectively Inventory, Net Inventory Assets Held For Sale Straight Path Ip Group Assets held for sale - Straight Path IP Group Assets held for sale straight path ip group Prepaid Expense and Other Assets, Current TOTAL PREPAID EXPENSES AND OTHER CURRENT ASSETS Prepaid expenses and other current assets Assets, Current Total current assets Prepaid Expenses Related To Sale Of Ip Business To Idt Prepaid expenses - related to the sale of Straight Path IP Group Prepaid expenses related to the sale of ip business to idt. Intangible Assets, Net (Excluding Goodwill) Intangible assets Other Assets, Noncurrent Other assets Assets Total assets Total assets Liabilities and Equity [Abstract] Liabilities and Deficiency Liabilities, Current [Abstract] Current liabilities: Accounts Payable, Trade, Current Trade accounts payable (related party of $57 and $29, respectively) Accrued Liabilities, Current Accrued expenses (related party of $0 and $900, respectively) Accrued expenses TOTAL ACCRUED EXPENSES Dividends Payable, Current Dividend payable Liabilities Held For Sale Straight Path Ip Group Liabilities held for sale - Straight Path IP Group Liabilities held for sale straight path ip group. Fcc Consent Decree Payable FCC consent decree payable Amount of liabilities Fcc consent decree payable. Loans Payable Loans payable, net of debt discount of $541 and $1,101 Loans payable Loans payable, net of debt discount Deferred Revenue, Current Deferred revenue Liabilities, Current Total current liabilities Estimated Litigation Liability, Noncurrent Settlement of litigation Deferred Revenue, Noncurrent Deferred revenue - long-term portion Liabilities TOTAL LIABILITIES Total liabilities Commitments and Contingencies Commitments and contingencies Equity [Abstract] Deficiency Equity Stockholders' Equity Attributable to Parent [Abstract] Straight Path Communications Inc. stockholders' deficiency: Preferred Stock, Value, Issued Preferred stock, $0.01 par value; 3,000 shares authorized; no shares issued and outstanding Common Stock, Value, Issued Common stock value Additional Paid in Capital Additional paid-in capital Retained Earnings (Accumulated Deficit) (Accumulated deficit) retained earnings Accumulated deficit Retained earnings Treasury Stock, Value Treasury stock, 40 shares at cost at October 31, 2017 and July 31, 2017 Stockholders' Equity Attributable to Parent Total Straight Path Communications Inc. stockholders' equity Total Straight Path Communications Inc. stockholders' deficiency Balance Balance Stockholders' Equity Attributable to Noncontrolling Interest Noncontrolling interests Noncontrolling interests Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total deficiency Balance Balance Liabilities and Equity Total liabilities and deficiency Equity Components [Axis] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Common Stock Allowance for Doubtful Accounts Receivable Net of allowance for doubtful accounts Allowance for doubtful accounts, Balance at beginning of year Allowance for doubtful accounts, Balance at end of year Accounts Payable, Related Parties, Current Trade accounts payable related party Accrued Expenses Related Parties Current Accrued expenses related party Amount for accounts payable to related parties. Debt Instrument, Unamortized Discount, Current Loans payable, net of debt discount Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Preferred Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Issued Preferred stock, shares issued Preferred Stock, Shares Outstanding Preferred stock, shares outstanding Common Stock, Par or Stated Value Per Share Common stock, par value Common Stock, Shares Authorized Common stock, shares authorized Common Stock, Shares, Issued Common stock shares distributed Common stock, shares issued Common Stock, Shares, Outstanding Common stock shares outstanding Common stock, shares outstanding Treasury Stock, Shares Treasury stock, shares Treasury stock, shares Statements of Operations [Abstract] Revenues Revenues Revenues Revenues Costs and Expenses [Abstract] Costs and expenses: Cost of Revenue Direct cost of revenues Research and Development Expense Research and development Research and development Research and development expenses Selling, General and Administrative Expense Selling, general and administrative expense Selling, general and administrative (related party of $21 and $128, respectively) Selling, general and administrative Selling, general and administrative Costs and Expenses Total costs and expenses Total costs and expenses Total costs and expenses Loss From Operations Before Profit Sharing Settlement Loss from operations before profit sharing settlement Loss from operations before profit sharing settlement. Loss from operations before profit sharing settlement Loss from operations before profit sharing settlement Profit Sharing Settlement Profit sharing settlement Profit sharing settlement. Profit sharing settlement Operating Income (Loss) Income (loss) from operations Income (loss) from operations Loss from operations Loss from operations Loss from operations Other Income and Expenses [Abstract] Other income (expense): Interest Expense Debt Including Amortization Interest expense including amortization of debt discounts Interest expense Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, including amortization of debt discount (premium) and financing costs. Interest expense including amortization of debt discounts Interest expense Interest Income, Other Interest income Other Income Income from IDT Corporation payments of liabilities Other income Income from IDT Corporation payments of liabilities Other Nonoperating Income (Expense) Other income Total other income (expense) Total other income (expense) Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Loss provision for income taxes Loss from continuing operations before provision for income taxes Income Tax Expense (Benefit) Income tax expense (benefit) BENEFIT FROM (PROVISION FOR) INCOME TAXES PROVISION FOR (INCOME TAXES) INCOME TAX BENEFITS INCOME TAX BENEFITS (PROVISION FOR INCOME TAXES) Provision for income tax benefits (income taxes) BENEFIT FROM (PROVISION FOR) INCOME TAXES Income tax benefits provision for income taxes Income tax benefits (provision for income taxes) Provision for income taxes Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Loss from continuing operations Loss from continuing operations Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Loss from discontinued operations: Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Loss from discontinued operations Loss from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest Loss from discontinued operations Loss attributable to noncontrolling interests Loss attributable to noncontrolling interests Income (Loss) Attributable to Noncontrolling Interest Net loss (income) attributable to noncontrolling interests Net loss attributable to noncontrolling interests Net loss attributable to noncontrolling interests Loss from discontinued operations attributable to Straight Path Communications Inc. Loss from discontinued operations attributable to Straight Path Communications Inc. Loss from discontinued operations attributable to Straight Path Communications Inc. Loss from discontinued operations attributable to Straight Path Communications Inc. Net Income (Loss) Attributable to Parent Net loss Net (loss) income Net loss attributable to SPCI Net loss attributable to Straight Path Communications Inc. Net (loss) income attributable to SPCI Net loss from discontinued operations attributable to Straight Path Communications Inc. Loss Per Share [Abstract] Loss per share attributable to Straight Path Communications Inc. stockholders: Income (Loss) from Continuing Operations, Per Basic and Diluted Share Basic and diluted - continuing operations Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic and Diluted Share Basic and diluted - discontinued operations Earnings Per Share, Basic and Diluted Basic and diluted - total Loss per share - basic and diluted Basic and diluted - total Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted-average number of shares used in calculation of loss per share: Weighted Average Number of Shares Outstanding, Basic and Diluted Basic and diluted Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party Selling, general and administrative related party Statements of Equity (Deficit) [Abstract] Additional Paid-in Capital [Member] Additional Paid-In Capital Additional Paid-In Capital [Member] Retained Earnings [Member] Accumulated Deficit Treasury Stock [Member] Treasury Stock Treasury Stock [Member] Noncontrolling Interest [Member] Noncontrolling Interests Noncontrolling Interests [Member] Shares, Outstanding Balance, shares Balance, shares Capital Contribution Related To Settlement Agreement And Release Capital contribution related to IDT settlement agreement and release Amount of capital contribution related to settlement agreement and release. Capital contribution related to IDT settlement agreement and release Adjustments To Additional Paid In Capital, Gain On Sale Of Assets Gain on sale of Straight Path IP Group Amount of increase (decrease) to additional paid in capital (APIC) resulting from changes in gain loss on assets. Adjustments To Additional Paid In Capital, Removal Of Noncontrolling Interests Due To Sale Of Assets Removal of noncontrolling interests due to sale of Straight Path IP Group Amount of increase (decrease) to additional paid in capital (APIC) resulting from changes in Removal of noncontrolling interests due to sale of assets. Stock Issued During Period, Value, Restricted Stock Award, Gross Stock-based compensation - restricted common stock Stock Issued During Period, Shares, Share-based Compensation, Gross Common stock issued for compensation, shares Stock-based compensation - restricted common stock, shares Stock Issued During Period, Value, Stock Options Exercised Common stock issued for exercises of stock options, value Common stock issued for exercises of stock options Common stock issued upon exercise of stock options Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Common stock issued for exercises of stock options, shares Stock options, Exercised Stock Issued During Period Common Stock Issued For Exercises Of Warrants Common stock issued for exercises of warrants Common stock issued for exercises of warrants. Stock Issued During Period Common Stock Issued For Exercises Of Warrants Shares Common stock issued for exercises of warrants, shares Common stock issued for exercises of warrants shares. Stock Issued During Period Issuance Of Warrants With Loans Payable Issuance of warrants with loans payable Issuance of warrants with loans payable. Stock Issued During Period Issuance Of Warrants With Loans Payable Shares Issuance of warrants with loans payable, shares Issuance of warrants with loans payable shares. Stock Issued During Period, Value, Stock Dividend Dividends Dividends Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net (loss) income Net (loss) income Net loss Net loss Net loss Statement of Cash Flows [Abstract] Net Cash Provided by (Used in) Operating Activities [Abstract] Operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash used in operating activities: Restricted Stock or Unit Expense Stock-based compensation - restricted common stock Stock or Unit Option Plan Expense Stock-based compensation - stock options Amortization of Debt Discount (Premium) Amortization of debt discounts Increase (Decrease) in Operating Capital [Abstract] Changes in assets and liabilities: Increase (Decrease) in Accounts Receivable Trade accounts receivable Trade accounts receivable, net Increase (Decrease) in Inventories Inventory Inventory Increase Decrease In Assets Held For Sale Intellectual Property Business Assets held for sale - Straight Path IP Group Increase decrease in assets held for sale intellectual property business. Increase (Decrease) in Prepaid Expenses, Other Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Prepaid expenses - related to sale of Straight Path IP Group Increase (Decrease) in Other Operating Assets Other assets Increase (Decrease) in Accounts Payable, Trade Trade accounts payable Increase (Decrease) in Accrued Liabilities Accrued expenses Increase Decrease In Liabilities Held For Sale Intellectual Property Business Liabilities held for sale - Straight Path IP Group Increase decrease in liabilities held for sale intellectual property business Increase Decrease Fcc Consent Decree Payable FCC consent decree payable The increase (decrease) in obligations consent decree payable. Increase (Decrease) in Deferred Revenue Deferred revenue Increase (Decrease) in Income Taxes Payable Income taxes payable Net Cash Provided by (Used in) Operating Activities Net cash used in operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Investing activities: Proceeds From Sale Of Intellectual Property Business Proceeds from sale of Straight Path IP Group The cash inflow from the sale of intellectual property business. Net Cash Provided by (Used in) Investing Activities Net cash provided by investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Financing activities: Capital Contribution Related To Settlement Agreement Capital contribution related to IDT settlement agreement and release Amount of cash inflow from Capital contribution related to settlement agreement. Payments of Dividends Dividends paid to stockholders of noncontrolling interests Dividend related to IDT settlement agreement and release Repayment Of Loans Payable The cash outflow from the repayment of loans payable. Payments of loans payable Costs Related To Loans Payable Costs related to loans payable Costs related to loans payable Proceeds from Warrant Exercises Proceeds from aggregate warrants Common stock issued upon exercise of warrants Proceeds from warrant exercise received Payments Of Stock Issuance Exercise Stock Option Value of payments of stock issuance exercise stock option. Common stock issued upon exercise of stock options Net Cash Provided by (Used in) Financing Activities Net cash provided by financing activities Cash and Cash Equivalents, Period Increase (Decrease) Net decrease in cash and cash equivalents Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Supplemental schedule of noncash activities Gain On Sale Of Straight Path Ip Group Classified As Additional Paid In Capital Gain on sale of Straight Path IP Group classified as additional paid-in capital The amount of gain on sale of Straight Path IP Group classified as additional paid-in capital. Elimination Of Noncontrolling Interests Due To Sale Of Intellectual Property Business Elimination of noncontrolling interests due to sale of Straight Path IP Group Elimination of noncontrolling interests due to sale of intellectual property business. Dividend Payable Dvidend payable The amount of dividend payable. Supplemental Cash Flow Information [Abstract] Supplemental cash flow information Interest Paid, Net Cash paid during the period for interest Income Taxes Paid Cash paid during the period for income taxes Basis of Presentation [Abstract] Basis of Accounting [Text Block] Basis of Presentation Verizon Merger Agreement [Abstract] Verizon Merger Agreement [Text Block] Verizon Merger Agreement The entire disclosure Verizon Merger Agreement. Settlement of Claims with IDT and Sale of Straight Path IP Group [Abstract] Settlement of Claims with IDT and Sale of Straight Path IP Group [Abstract] Settlement Of Claims With Idt And Sale Of Straight Path Ip Group [Text Block] Settlement of Claims with IDT and Sale of Straight Path IP Group The entire disclosure of settlement of claims. Summary of Significant Accounting Policies and Recent Pronouncements [Abstract] Significant Accounting Policies [Text Block] Summary of Significant Accounting Policies and Recent Pronouncements Fair Value Measures [Abstract] Fair Value Disclosures [Text Block] Fair Value Measures Inventory [Abstract] Inventory Disclosure [Text Block] Inventory Loan Payable [Abstract] Debt Disclosure [Text Block] Loan Payable Stockholders' Equity Note Disclosure [Text Block] Equity Stock-Based Compensation [Abstract] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-Based Compensation Earnings Per Share [Text Block] Loss Per Share Related Party Transactions [Abstract] Related Party Transactions [Abstract] Related Party Transactions Disclosure [Text Block] Related Party Transactions Income Taxes [Abstract] Income Taxes Income Taxes Business Segment Information [Abstract] Business Segment Information Segment Reporting Disclosure [Text Block] Business Segment Information Commitments and Contingencies [Abstract] Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies New Accounting Pronouncements, Policy [Policy Text Block] Summary of Significant Accounting Policies and Recent Pronouncements Disposal Groups, Including Discontinued Operations [Table Text Block] Schedule of discontinued operations of straight path IP group Schedule of Assumptions Used [Table Text Block] Schedule of fair value of the warrants using the Black-Scholes option pricing model Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] Schedule of options warrant activity Schedule Of Warrants Outstanding And Exercisable [Table Text Block] Schedule of warrants and excercisable The entire disclosure of warrants outstanding and exercisable. Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Summary of shares excluded from diluted earnings per share computations Schedule of Weighted Average Number of Shares [Table Text Block] Schedule of number of stock options to purchase Class B common stock which were excluded from the diluted per share Schedule of Segment Reporting Information, by Segment [Table Text Block] Summary of operating results for the business segments Reconciliation of Assets from Segment to Consolidated [Table Text Block] Summary of total assets for the business segments Schedule of Subsidiary of Limited Liability Company or Limited Partnership [Table] Consolidated Entities [Axis] Consolidated Entities [Domain] Subsidiaries [Member] Straight Path [Member] Subsidiaries One [Member] Straight Path IP Group [Member] Legal Entity [Axis] Entity [Domain] Straight Path Spectrum [Member] Straight Path Spectrum [Member] Straight Path Spectrum [Member] Entity owned or controlled by another entity. Subsidiary of Limited Liability Company or Limited Partnership [Line Items] Basis Of Presentation Textual [Abstract] Basis of Presentation (Textual) Initial Penalty Payment Initial civil penalty payment Initial penalty payment. Litigation Settlement, Expense Settlement of litigation Legal expense Settlement of initial payment Stockholder settlement Settlement of initial payment Settlement of litigation Settlement of litigation Additional Settlement Payment Additional settlement payment Additional settlement payment Additional settlement payment. Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions Percentage of ownership Ownership in straight path spectrum Verizon Merger Agreement [Table] Title of Individual [Axis] Relationship to Entity [Domain] Former Chief Executive Officer Of Straight Path Spectrum [Member] Former SPSI CEO [Member] Superior Offer [Member] Superior offer [Member] Superior offer member. Related Party [Axis] Related Party [Domain] Jonathan Rand [Member] Rand [Member] Zhouyuepi And David Breau [Member] Breau [Member] Davidi Jonas [Member] Jonas [Member] Financial Instrument [Axis] Financial Instruments [Domain] Verizon Merger Agreement [Member] Verizon merger agreement member. Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Verizon Merger Agreement [Line Items] Verizon Merger Agreement Textual [Abstract] Verizon Merger Agreement (Textual) Stock Issued During Period, Value, New Issues Nonassessable shares of common stock, value Merger Consideration Description Merger consideration, description Merger consideration description. Merger Agreement Termination Fees Termination fee The amount of termination fees in merger agreement during the reporing period. Parent Termination Fee Parent termination fee It represent parent termination fee for the reporting period. Payments for Merger Related Costs Incurred costs in merger agreement Payments To Future Revenue From Spectrum Percentage Payment to consent decree, percentage Payments to future revenues from spectrum, Percentage. Financial Advisor And Legal Fees Financial advisor and legal fees Financial advisor and legal fees. Related Party Transaction, Due from (to) Related Party, Current Balance owed of straight path spectrum Retention Bonus Payment Retention bonus payment Retention bonus payment. Equity Method Investment, Ownership Percentage Special meeting voting percentage Percentage of net proceeds received by shareholders Payments of Merger Related Costs, Financing Activities Verizon merger agreement payaments Repayaments Of Verizon Merger Agreement Repayaments of verizon merger agreement Repayaments of verizon merger agreement. Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Group Name [Domain] Discontinued Straight Path Ip Group [Member] Discontinued Straight Path IP Group [Member] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Discontinued operations of Straight Path IP Group (Line Items) Net Income (Loss) Attributable to Noncontrolling Interest Loss attributable to noncontrolling interests Settlement Of Claims With Idt And Sale Of Straight Path Ip Group Textual [Abstract] Settlement of Claims with IDT and Sale of Straight Path IP Group (Textual) Repayments of Related Party Debt Payment of IDT Total Incurred Cost Of Negotiation And Execution Of Term Sheet Total incurred costs of negotiation and execution of term sheet Total incurred cost of negotiation and execution of term sheet. Recognized a profit Recognized a profit Assets Held-in-trust Company contributed to trust Payments For Remaining Trust Amount Payement of remaining trust The payment of remaining trust amount. Agreed To Contribution To Assets To Be Held In Trust Agreed amount to contribute to trust Agreed to contribution to assets to be held-in-trust. Members' Equity Payment for ownership interest Schedule of Long-term Debt Instruments [Table] Range [Axis] Range [Domain] Minimum [Member] Maximum [Member] Debt Instrument [Line Items] Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract] Schedule of fair value assumptions Fair Value Assumptions, Risk Free Interest Rate Risk-free rate Risk-free interest rate Fair Value Assumptions, Expected Dividend Rate Dividend yield Fair Value Assumptions, Expected Volatility Rate Volatility Fair Value Assumptions, Expected Term Expected term (in years) Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Loan Agreement [Member] Loan Agreement [Member] Loan Payable Textual [Abstract] Loan Payable (Textual) Other Loans Payable Borrowed from investors Debt Instrument, Interest Rate, Effective Percentage Interest rate Debt Instrument, Interest Rate, Increase (Decrease) Interest rate, increased Debt Instrument, Maturity Date Loan maturity date Payments Of Initial Civil Penalty Payments of initial civil penalty Payments of initial civil penalty for the reporting period. Payments Of First Installments Payments of first installments Payments of first installments for the reporting period. Warrants Issued To Purchase Of Common Stock Warrant issued to purchase common stock Warrants issued to purchase of common stock for the reporting period. Percentage Of Warrant Description Percentage of warrant description Percentage of warrant description. Fair Value Adjustment of Warrants Fair value of warrants Payments of Loan Costs Cash costs Interest Expense, Debt, Excluding Amortization Amortization amount Depreciation and Amortization, Discontinued Operations Amortization in discontinued operations Interest Expense, Debt Interest expense, debt Interest Paid, Discontinued Operations Interest expense in discontinued operations Debt Instrument, Unamortized Discount Unamortized debt discounts Class of Warrant or Right, Exercise Price of Warrants or Rights Warrants exercise price Investment Warrants Expiration Date Warrants expire date Investment Company, Fee Waiver Terms Amendment and waiver agreement, description Class of Warrant or Right [Table] Warrant [Member] Warrants [Member] Warrants [Member] Class of Warrant or Right [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number Warrants Outstanding, Ending Balance Warrants Outstanding, Beginning Balance Warrants Outstanding, and exercisable Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Warrants, Granted Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised Warrants, Exercised Warrants, Exercised Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures Warrants, Cancelled/Forfeited Share Based Compensation Arrangement By Share Based Payment Award Non Option Outstanding Weighted Average Number Of Share Warrants Outstanding, Weighted-average Exercise Price Weighted-average Exercise Price, Beginning Balance Weighted-average Exercise Price Outstanding and Exercisable It represents weighted average excercise price beginning balance. Share Based Compensation Arrangement By Share Based Payment Award Non Option Granted In Period Weighted Average Exercise Price Weighted-average Exercise Price, Granted It represents weighted average excercise price granted. Share Based Compensation Arrangement By Share Based Payment Award Non Option Exercised In Period Weighted Average Exercise Price Weighted-average Exercise Price, Exercised It represents weighted average excercise price granted. Share Based Compensation Arrangement By Share Based Payment Award Non Option Cancelled Or Forfeited In Period Weighted Average Exercise Price Weighted-average Exercise Price, Cancelled/Forfeited It represents weighted average excercise price forfeited. Share Based Compensation Arrangement By Share Based Payment Award Non Option Outstanding In Period Weighted Average Remaining Contractual Term Weighted-average Remaining Contractual Term (in years), Outstanding Warrants Outstanding, Weighted-Average Remaining Life In Years It represents weighted average remaining contractual term. Share Based Compensation Arrangement By Share Based Payment Award Non Option Excercisable In Period Weighted Average Remaining Contractual Term Weighted-average Remaining Contractual Term (in years), Exercisable It represents weighted average excercisable remaining contractual term. Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Aggregate Intrinsic Value, Beginning Balance Aggregate Intrinsic Value, Outstanding and exercisable Exercise Price Range [Axis] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Exercise Price One [Member] $ 34.70 [Member] Exercise Price Two [Member] $ 179.18 - $180.48 [Member] Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instrument Excercisable Warrants, Excercisable Warrants Outstanding, Number Exercisable It represents warrants excercisable. Schedule of Stock by Class [Table] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Domain] Employee Stock Option [Member] Stock options [Member] Stock Options [Member] Related Party Transaction [Axis] Related Party Transaction [Domain] Idt [Member] IDT[Member] IDT Chief Executive Officer And President [Member] Jonas [Member] Officer [Member] Other officers [Member] Consultant [Member] Consultant [Member] Consltant member. Two Employees [Member] A person employed for wages or salary, especially at non-executive level. Non Employee Directors [Member] Non employee directors [Member] Non employee directors. Officers Directors And Consultants [Member] Officers, directors and consultants [Member] Officers directors and consultants. Directors And Officers [Member] Directors and officers [Member] Directors and officers. Employee [Member] Employee [Member] Other employees (Member) Employee member. Dividends [Axis] Dividends [Domain] Dividend Declared [Member] Dividends [Member] Class of Stock [Line Items] Equity (Textual) [Abstract] Equity (Textual) Treasury Stock Repurchased Value Number of shares held in treasury stock value Amount of treasury stock repurchased value. Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instrument Aggregate Intrinsic Value Exercised Intrinsic value of warrants exercised It represents share based compensation arrangement by share based payment award non option equity instrument aggregate intrinsic value exercised. Closing Stock Price Per Share Closing stock price Closing stock price per share. Stock Issued During Period Shares Warrants Exercised Common stock issued for exercises of warrants, shares Number of share warrants (or share units) exercised during the current period. Issuances Of Warrants To Purchase Issuances of warrants to purchase Issuances of warrants to purchase. Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Income Statement Location [Axis] Income Statement Location [Domain] Selling, General and Administrative Expenses [Member] Selling, General and Administrative Expenses [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Stock Based Compensation (Textual) [Abstract] Stock-Based Compensation (Textual) Common Stock, Capital Shares Reserved for Future Issuance Common stock shares reserved Share-based Compensation Stock options issued for compensation Stock-based compensation Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Restricted common stock non vested -shares Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized compensation cost related to non-vested restricted share value Unrecognized Compensation Cost Due In Next Twelve Months Unrecognized compensation cost in fiscal 2018 Amount of the unrecognized compensation cost due in next twelve months. Unrecognized Compensation Cost Due Within Two Years Unrecognized compensation cost in fiscal 2019 Amount of the unrecognized compensation cost due within two years. Unrecognized Compensation Cost Due Within Three Years Unrecognized compensation cost in fiscal 2020 Amount of the unrecognized compensation cost due within three years. Unrecognized Compensation Cost Due Within Four Years Unrecognized compensation cost in fiscal 2021 Amount of the unrecognized compensation cost due within four years. Non Vested Restricted Classb Common Stock [Member] Non-vested restricted Class B common stock [Member] Non-vested restricted Class B common stock [Member] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Earnings Per Share, Diluted, Other Disclosures [Abstract] Shares excluded from the diluted earnings per share computations Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Shares excluded from the calculation of diluted loss per share Dilutive Securities Excluded From Computation Of Earnings Per Share Amount Shares excluded from the calculation of diluted loss per share Number of dilutive securities excluded from computation of earnings per share. Schedule of Related Party Transactions, by Related Party [Table] International Discount Telecommunications [Member] IDT [Member] International discount telecommunications. Law Firm [Member] Law firm [Member] Related Party Transaction [Line Items] Related Party Transactions (Textual) [Abstract] Related Party Transactions (Textual) Legal Fees Non-refundable fee Legal fees Finite-lived Intangible Assets Acquired Law firm owned accounts payable Payments for Legal Settlements Legal accrued expense Schedule of Segment Reporting Information, by Segment [Table] Straight Path Ip [Member] Straight Path IP Group [Member] Straight Path IP [Member] Straight Path Ventures [Member] Straight Path Ventures [Member] Straight path ventures member. Segment Reporting Information [Line Items] Segment Reporting Information, Profit (Loss) [Abstract] Summary of operating results for the business segments Segment Reporting Information, Additional Information [Abstract] Summary of total assets for the business segments Gigabit Mobility Lab [Member] Chief Technology Officer [Member] One Employee [Member] Other Employees [Member] One Other Employee [Member] General and Administrative Expense [Member] Business Segment Information (Textual) [Abstract] Business Segment Information (Textual) Number of Reportable Segments Reportable segments Percentage Of Employment Expenses Employment expenses of Chief Technology Officer Percentage of employment expenses. Percentage of employment expenses Product Liability Contingency [Table] Straight Path Spectrum Spectrum Licenses [Member] Straight Path Spectrum'S Spectrum Licenses [Member] Straight Path Spectrums spectrum licenses. Former Chief Executive Officer [Member] Former Chief Executive Officer [Member] Former Chief Executive Officer [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Economic Area License [Member] 39 GHz Economic Area [Member] Economic area license. Rectangular Service Area License [Member] 39 GHz Rectangular Service Area [Member] Rectangular service area license. Local Multipoint Distribution Service License [Member] LMDS 28 GHz range [Member] Five Hundred Point To Multipoint Radios [Member] 500 PMP radios [Member] Other Commitments [Axis] Other Commitments [Domain] Licenses Expire On Two Thousand Eighteen August Ten [Member] Licenses expire on august 10, 2018 [Member] Licenses Expire On Two Thousand Eighteen September Twenty One [Member] Licenses expire on september 21,2018 [Member] Geographical [Axis] Geographical [Domain] NEW YORK Product Liability Contingency [Line Items] Commitments And Contingencies Textual [Abstract] Commitments and Contingencies (Textual) Percentage Of Amount Recovered From Patent Infringers Paid To Law Firm Recoverable contingency patents allegedly infringed, percentage Percentage of amount recovered from patent infringers paid to law firms. Prepaid Expense Fee Prepaid expense fee Represents prepaid expense fee. License Expiration Date License expiration date Date which license is set to establish a new expiration date must be form in CCYY-MM-DD format. Payments for Rent Monthly rent Operating Leases, Rent Expense, Net Annual rent Other Commitments, Description Extended term date, description Lease Agreement Description Lease agreement, description Description of lease agreement. Operating Leases, Rent Expense Rental expense, operating leases Licenses To Be Expired Licenses to be expired Number of licenses to be expired. Loss Contingency, Patents Allegedly Infringed, Number Infringe of patents Payments From Future Revenue From Spectrum Percentage Payments to be made from revenue, percentage Payments from future revenues from spectrum, Percentage. Maximum Future Payment For Wireless Spectrum Licenses Amount of maximum future payment for wireless spectrum licenses Maximum future payment for wireless spectrum licenses. Cumulative Amount Paid For Payment From Future Revenues From Spectrum Obligation Cumulative amount paid for payment from future revenues from spectrum obligation Amount incurred for obligation Cumulative amount paid for payment from future revenues from spectrum obligation. Acquisition Costs, Period Cost Acquisition costs Deposits Accounts Payable Accounts payable Installment Value Installment value Installment value. Number Of Instalments Number of installments Number of instalments. Initial Civil Penalty Initial civil penalty Initial civil penalty. Payments Of Additional Penalty Payments of additional penalty Payments of additional penalty. Payment Of Two Installments Of Initial Civil Penalty Payment of three installments of initial civil penalty Payment two installments of initial civil penalty. Consent Decree Payable FCC consent decree payable Consent decree payable. Payment Of Penalty Payment of penalty Payment of penalty. Additional payment Additional payment Loan From Lenders Loans from lenders Loan from Lenders. Loss Contingency, Settlement Agreement, Terms Description of legal settlement agreement Debt Instrument, Frequency of Fee Description of monthly fee Percentage Of Profit Share Percentage of profit share Percentage price of original principal amount of license agreement with PTPM can be issued by the net proceeds from any partition, sales, assignment, etc.,