Note 3 - Revenue 1 (Details Textual)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Percentage of Revenue Transferred to Customers	75.00%	88.00%
Revenue Remaining Performance Obligation, Customers Upon Shipment With Payment Terms (Day)	120 days

Period in which remaining performance obligation customers upon shipment with payment terms, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	nsys_RevenueRemainingPerformanceObligationCustomersUponShipmentWithPaymentTerms
Namespace Prefix:	nsys_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration