Represents the number of divisions related to concentration risk.

No definition available.

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Namespace Prefix:	nsys_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of high credit quality financial institution with whom excess cash balances are maintained for checking accounts.

+ References

No definition available.

+ Details

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Namespace Prefix:	nsys_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the export sales, expressed as a percentage of consolidated net sales.

+ References

No definition available.

+ Details

Name:	nsys_PercentageOfExportSalesToConsolidatedSales
Namespace Prefix:	nsys_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- 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

Name:	us-gaap_ConcentrationRiskLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_StatementGeographicalAxis=country_CN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=nsys_DivisionOneOfLargestCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=nsys_OtherDivisionOfLargestCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=nsys_DivisionsOneAndOtherOfLargestCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix:
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CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019 USD ($) item division	Mar. 31, 2018	Dec. 31, 2018
Major customers and concentration of credit risk
Cash	$ 310
Largest customer
Major customers and concentration of credit risk
Number of divisions \| division	2
China
Major customers and concentration of credit risk
Cash	$ 276
Credit concentration risk
Major customers and concentration of credit risk
Excess cash balance, number of high credit quality financial institutions \| item	2
Net sales \| Customer concentration risk
Major customers and concentration of credit risk
Percentage of export sales to consolidated net sales	19.00%	19.00%
Net sales \| Customer concentration risk \| Division one of largest customer
Major customers and concentration of credit risk
Percentage of concentration risk (as a percent)	23.00%	19.00%
Net sales \| Customer concentration risk \| Other division of largest customer
Major customers and concentration of credit risk
Percentage of concentration risk (as a percent)	3.00%	1.00%
Net sales \| Customer concentration risk \| Divisions one & other
Major customers and concentration of credit risk
Percentage of concentration risk (as a percent)	26.00%	20.00%
Net sales \| Customer concentration risk \| Minimum \| Largest customer
Major customers and concentration of credit risk
Percentage of concentration risk (as a percent)	10.00%	10.00%
Accounts receivable \| Customer concentration risk \| Largest customer
Major customers and concentration of credit risk
Percentage of concentration risk (as a percent)	25.00%		16.00%