REVENUE - Net sales by market (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Product/Service Transferred Over Time	$ 24,049
Product Transferred at Point in Time	1,373
Noncash Consideration	1,025
Total Net Sales by Market	26,447
Aerospace and Defense
Product/Service Transferred Over Time	4,623
Product Transferred at Point in Time	48
Noncash Consideration	195
Total Net Sales by Market	4,866
Medical
Product/Service Transferred Over Time	9,434
Product Transferred at Point in Time	482
Noncash Consideration	405
Total Net Sales by Market	10,321
Industrial
Product/Service Transferred Over Time	9,992
Product Transferred at Point in Time	843
Noncash Consideration	425
Total Net Sales by Market	$ 11,260

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

No definition available.

Name:	nsys_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	nsys_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration