REVENUE - Contract Assets (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Increase (decrease) contract assets
Outstanding at the end of year	$ 6,431
Revenue under contract manufacturing agreements (as percentage)	91.00%
Remaining performance obligations customers upon shipment with payment terms	120 days
ASU 2014-09
Increase (decrease) contract assets
Outstanding at the beginning of year	$ 6,459
Transferred to receivables from contract assets recognized	(5,932)
Product transferred over time	5,904
Outstanding at the end of year	$ 6,431

The increase (decrease) during the reporting period in product transferred over time.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Represents the percentage of revenue under contract manufacturing agreements that was recognized.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	nsys_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Details

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