Document and Entity Information [Abstract] Statement [Table] Class of Stock [Axis] Class of Stock [Domain] Common Class A [Member] Common Class A [Member] Class A common stock Class B 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 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] To Be Issued Common stock to be issued Represent information of common stock to be issued. Scenario [Axis] Scenario, Unspecified [Domain] Pro forma [Member] Pro forma Assets [Abstract] Assets Assets, Current [Abstract] Current assets: Cash and cash equivalents at beginning of period Cash and cash equivalents Cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash and cash equivalents Restricted cash Restricted cash Restricted cash Accounts Receivable, Net, Current Trade accounts receivable, net Trade accounts receivable, net of allowance for doubtful accounts of $7 and $0, respectively Inventory Inventory Prepaid Expense, Current Prepaid expenses and other current assets Prepaid expenses and other current assets Assets, Current Total current assets Intangible Assets, Net (Excluding Goodwill) Intangible assets Intangible assets Other Assets, Noncurrent Other assets Other assets Assets Total assets: Total assets Liabilities and Equity (Deficiency) Liabilities and Equity (Deficiency) Liabilities, Current [Abstract] Current liabilities: Current liabilities: Accounts Payable, Trade, Current Trade accounts payable Trade accounts payable (related party of $43 and $0) Accrued Liabilities, Current Prepaid expenses Accrued expenses TOTAL Accrued expenses Loan payable, net of debt discount Loan payable, net of debt discount FCC consent decree payable FCC consent decree payable Amount of liabilities Fcc consent decree Payable Deferred Revenue, Current Deferred revenue Deferred revenue Taxes Payable, Current Income taxes payable Income taxes payable Liabilities, Current Total current liabilities Settlement payable - stockholders Deferred Revenue, Noncurrent Deferred revenue - long-term portion Deferred revenue - long-term portion Liabilities Total liabilities Total liabilities Commitments and Contingencies Commitments and contingencies Equity [Abstract] Equity (Deficiency) Stockholders' Equity Attributable to Parent [Abstract] Straight Path Communications Inc. stockholders' equity: Straight Path Communications Inc. stockholders' equity: Preferred Stock, Value, Issued Preferred stock Preferred stock, $0.01 par value; 3,000 shares authorized; no shares issued and outstanding Additional Paid in Capital Additional paid-in capital Additional paid-in capital Retained Earnings (Accumulated Deficit) Accumulated deficit Accumulated deficit Accumulated deficit Treasury Stock, Value Treasury stock, value Number of shares held in treasury stock, value Treasury stock Treasury stock, value Stockholders' Equity Attributable to Parent Total Straight Path Communications Inc. stockholders' equity (deficiency) Common Stock, Value, Issued Common stock value Class A common stock, $0.01 par value; 2,000 shares authorized;787 shares issued and outstanding Stockholders' Equity Attributable to Noncontrolling Interest Noncontrolling interests Noncontrolling interests Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total equity (deficiency) Balance Balance Liabilities and Equity Liabilities and equity Total liabilities and equity (deficiency) Beginning balance Ending Balance Equity Components [Axis] Equity Component [Domain] Common Stock 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 Accounts payable, related party 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 Balance (in shares) Balance (in shares) Treasury Stock, Shares Treasury stock, shares Statements of Operations [Abstract] 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 expenses Selling, General and Administrative Expense Included in Selling, general and administrative expenses Selling, general and administrative (related party of $205, $0, $205, and $0) Costs and Expenses Total costs and expenses Loss From Operations Before Item Listed Below Loss from operations before item listed below Loss from operations before item listed below Loss from operations before item listed below Civil Penalty Fcc Decree Civil penalty - Fcc decree A civil penalty or civil fine is a financial penalty imposed by a government agency as restitution for wrongdoing. Civil penalty - FCC decree Stockholder Settlement Stockholder settlement The Parties have reached an agreement to settle the shareholder. Stockholder settlement Operating Income (Loss) Loss from operations before FCC Decree and stockholder settlement Income (loss) from operations Loss from operations Other Income and Expenses [Abstract] Other income: Interest Income, Other Interest income Other Income Other income Interest and Other Income Total other income Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest Income (loss) before income taxes Loss before income taxes Income Tax Expense (Benefit) Provision for income taxes PROVISION FOR INCOME TAXES Provision for income taxes Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net loss Net loss Net loss Income (Loss) Attributable to Noncontrolling Interest Net loss attributable to noncontrolling interests Net loss attributable to noncontrolling interests Net Income (Loss) Attributable to Parent Net loss Net (loss) income Net loss attributable to Straight Path Communications Inc. Earnings (loss) per share attributable to Straight Path Communications Inc. stockholders: Loss per share attributable to Straight Path Communications Inc. stockholders: Earnings Per Share, Basic and Diluted Basic and diluted 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 Statement of Stockholders' Equity [Abstract] Additional Paid-in Capital [Member] Additional Paid-In Capital Retained Earnings [Member] Accumulated Deficit Treasury Stock [Member] Treasury Stock Noncontrolling Interest [Member] Noncontrolling Interests Shares, Outstanding Common stock, shares outstanding Common stock, Shares outstanding Balance, shares Balance, shares Stock Issued During Period, Value, Stock Options Exercised Common stock issued for exercises of stock options Common stock issued for exercises 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 Common stock issued for exercises of stock options, shares Stock Issued During Period, Value, Share-based Compensation, Gross Common stock issued for compensation Common stock issued for compensation Common stock issued or to be issued for compensation Stock Issued During Period, Shares, Share-based Compensation, Gross Common stock issued for compensation, shares Stock issued during period as compensation, Shares Stock issued during period as compensation Stock issued during period as compensation, Shares Stock Issued During Period, Value, Share-based Compensation, Forfeited Stock-based compensation is included in selling, general and administrative Stock-based compensation Statement of Cash Flows [Abstract] Net Cash Provided by (Used in) Operating Activities [Abstract] Operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] 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: Allocated Share-based Compensation Expense Common stock issued for compensation Share-based Compensation Common stock issued for compensation Stock-based compensation Stock-based compensation is included in selling, general and administrative Common stock issued or to be issued for compensation Provision for Doubtful Accounts Allowance for doubtful accounts Increase (Decrease) in Operating Capital [Abstract] Changes in assets and liabilities: Increase (Decrease) in Accounts Receivable Trade accounts receivable, net Trade accounts receivable, net Increase (Decrease) in Inventories Inventory Increase (Decrease) in Prepaid Expense Prepaid expenses - settlements Prepaid expenses - related to IP settlements and licensing Increase (Decrease) in Prepaid Expenses, Other Prepaid expenses and other current assets Increase Decrease In Prepaid Expenses Development Agreement Prepaid expenses - development agreement Prepaid expenses - development agreement Represent amount of Prepaid expenses development agreement. Prepaid expenses - development agreement Increase (Decrease) in Other Operating Assets, Total Other assets Other assets Increase (Decrease) in Accounts Payable, Trade Trade accounts payable Increase (Decrease) in Accrued Liabilities Accrued expenses 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 Income taxes payable Increase (Decrease) in Due to Officers and Stockholders Settlement payable - stockholders Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net cash used in operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Investing activities: Payments to Acquire Property, Plant, and Equipment Purchases of property and equipment Purchases of property and equipment Net Cash Provided by (Used in) Investing Activities Net cash used in investing activities Net cash used in investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Financing activities: Proceeds from Stock Options Exercised Common stock issued upon exercise of stock options Net Cash Provided by (Used in) Financing Activities Net cash provided by 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 Noncash Reclassification Of Prepaid Marketing To Inventory Reclassification of prepaid marketing to inventory The amount of non cash reclassification of prepaid marketing to inventory. Noncash Unpaid Deferred Loan Costs Unpaid deferred loan costs The amount of non cash unpaid deferred loan cost. Supplemental cash flow information [Abstract] Supplemental cash flow information Income Taxes Paid, Net Cash paid during the period for income taxes Purchase of intangibles Basis of Presentation [Abstract] Basis of Accounting [Text Block] Basis of Presentation Basis of Presentation Summary of Significant Accounting Policies and Recent Pronouncements [Abstract] Basis of Presentation [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 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 (Loss) Per Share [Abstract] (Loss) earnings per share attributable to Straight Path Communications Inc. stockholders: Earnings Per Share [Text Block] Earnings (Loss) Per Share Related Party Transactions [Abstract] Related Party Transactions [Abstract] Related Party Transactions Disclosure [Text Block] Related Party Transactions Income Taxes [Abstract] Income Tax Disclosure [Text Block] 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 Subsequent Events [Abstract] Subsequent Event, Pro Forma Business Combinations or Disposals [Text Block] Subsequent Event, Pro Forma New Accounting Pronouncements, Policy [Policy Text Block] Summary of Significant Accounting Policies and Recent Pronouncements Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Summary of shares excluded from the diluted earnings per share computations Schedule of Weighted Average Number of Shares [Table Text Block] Schedule of the exercise price was greater than the average market price of the Class B common shares 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 Business Acquisition, Pro Forma Information [Table Text Block] Schedule of Proforma Consolidated Balance Sheets Schedule of Subsidiary of Limited Liability Company or Limited Partnership [Table] Legal Entity [Axis] Entity [Domain] Subsidiaries [Member] Straight Path Spectrum [Member] Straight Path [Member] Subsidiaries [Member] Subsidiaries One Member Straight Path IP Group [Member] Straight Path IP Group [Member] Subsidiaries One. Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Subsidiary of Limited Liability Company or Limited Partnership [Line Items] Basis of Presentation (Textual) Basis Of Presentation Textual [Abstract] Basis of Presentation (Textual) Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions Ownership in straight path spectrum Initial Penalty Payment Initial penalty payment Initial penalty payment. Litigation Settlement, Expense Settlement of initial payment Additional Settlement Payment Additional settlement payment Additional settlement payment. Schedule of Stock by Class [Table] Title of Individual [Axis] Relationship to Entity [Domain] Officer [Member] Officers [Member] Employee [Member] Other Employees [Member] Represents employee. Chief Executive Officer [Member] Davidi Jonas [Member] Consultant [Member] Consultant [Member] Director [Member] Directors [Member] Treasury Stock, Common [Member] Treasury Stock, Common [Member] Option Indexed to Issuer's Equity [Axis] Option Indexed to Issuer's Equity, Type [Domain] Stock options [Member] Stock options [Member] Shares underlying stock options [Member] Class of Stock [Line Items] Equity (Textual) Equity Textual [Abstract] Equity (Textual)