Annual report pursuant to Section 13 and 15(d)

COMMITMENTS AND CONTINGENCIES - Legal Fees (Details Narrative)

v2.4.1.9
COMMITMENTS AND CONTINGENCIES - Legal Fees (Details Narrative) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Legal Service Agreement With Russ, August Kabot For Litigation Filed In April 2014 [Member]    
Legal Fees payment ,Terms Legal fees on a full contingency basis ranging from 15% to 30% of the net recovery (after deduction for expenses)  
Legal Service Agreement With Dovel And Luner For Litigation Settlement In May 2013 [Member]    
Legal Fees payment ,Terms Legal fees on a contingency basis ranging from 25% to 40% of the net recovery (after deduction of expenses)  
Legal Service Agreement With Dovel And Luner For Litigation Settlement In July 2010 [Member]    
Legal Fees payment ,Terms Aggregate cash payment of $1.5 million plus a contingency fee of 24%  
Legal fees and expenses $ 2,712,000us-gaap_LegalFees
/ us-gaap_LitigationStatusAxis
= nssi_LegalServiceAgreementWithDovelAndLunerForLitigationSettlementFiledInJuly2010Member
$ 1,611,000us-gaap_LegalFees
/ us-gaap_LitigationStatusAxis
= nssi_LegalServiceAgreementWithDovelAndLunerForLitigationSettlementFiledInJuly2010Member
Legal Service Agreement-Blank Rome [Member]    
Legal Fees payment ,Terms Once the Company recovers its expenses related to the litigation it is obligated to pay legal fees to Blank Rome LLP equal to 24% of the royalty revenue received by the Company from its license agreement with D-Link  
Legal fees and expenses 55,000us-gaap_LegalFees
/ us-gaap_LitigationStatusAxis
= nssi_LegalServiceAgreementWithBlankRomeMember
41,000us-gaap_LegalFees
/ us-gaap_LitigationStatusAxis
= nssi_LegalServiceAgreementWithBlankRomeMember
Legal Service Agreement With Dovel And Luner For Litigation Filed In September 2011 [Member]    
Legal Fees payment ,Terms Legal fees on a full contingency basis ranging from 12.5% to 35% (with certain exceptions) of the net recovery (after deduction for expenses)  
Legal fees and expenses 239,000us-gaap_LegalFees
/ us-gaap_LitigationStatusAxis
= nssi_LegalServiceAgreementWithDovelAndLunerForLitigationFiledInSeptember2011Member
 
Legal Service Agreement With Dovel And Luner For Litigation Filed In September 2011 [Member]    
Legal fees and expenses   $ 206,000us-gaap_LegalFees
/ us-gaap_LitigationCaseAxis
= nssi_LegalServiceAgreementWithDovelAndLunerForLitigationFiledInSeptember2011Member