Quarterly report pursuant to Section 13 or 15(d)

STOCK REPURCHASE PROGRAM (Details Narrative)

v2.4.1.9
STOCK REPURCHASE PROGRAM (Details Narrative) (USD $)
3 Months Ended 44 Months Ended
Mar. 31, 2015
Mar. 31, 2015
Aug. 22, 2011
Jun. 03, 2011
Number of shares, common stock subject to repurchase 828,600us-gaap_WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation 6,527,668us-gaap_WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation    
Average price per share, common stock subject to repurchase $ 2.25nssi_WeightedAveragePricePerShareCommonStockSubjectToRepurchase $ 1.63nssi_WeightedAveragePricePerShareCommonStockSubjectToRepurchase    
Aggregate cost of common stock repurchase $ 1,866,000us-gaap_PaymentsForRepurchaseOfEquity $ 10,624,000us-gaap_PaymentsForRepurchaseOfEquity    
Board of Directors [Member]        
Stock Repurchase Program, dollar amount of shares authorized to be repurchased     2,000,000us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased
/ us-gaap_TitleOfIndividualAxis
= us-gaap_BoardOfDirectorsChairmanMember
 
Stock Repurchase Program, doller amount of additional shares authorized to be repurchased       5,000,000us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
/ us-gaap_TitleOfIndividualAxis
= us-gaap_BoardOfDirectorsChairmanMember
Stock Repurchase Program, dollar amount of shares to be repurchase since inception       12,000,000nssi_StockRepurchaseProgramdollarAmountOfSharesToBeRepurchaseSinceInception
/ us-gaap_TitleOfIndividualAxis
= us-gaap_BoardOfDirectorsChairmanMember