Leverage Ratio

No definition available.

Name:	ntct_LeverageRatio
Namespace Prefix:	ntct_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of credit facility increase in amount term

+ References

No definition available.

+ Details

Name:	ntct_LineOfCreditFacilityIncreaseInAmountTerm
Namespace Prefix:	ntct_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of foreign subsidiaries capital stock to be used for repayment of line of credit

+ References

No definition available.

+ Details

Name:	ntct_PercentageOfForeignSubsidiariesCapitalStockToBeUsedForRepaymentOfLineOfCredit
Namespace Prefix:	ntct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Spread Over Interest Rate

+ References

No definition available.

+ Details

Name:	ntct_SpreadOverInterestRate
Namespace Prefix:	ntct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	ntct_DebtInstrumentInterestRateByInterestTypeAxis=ntct_FederalFundsEffectiveRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ntct_DebtInstrumentInterestRateByInterestTypeAxis=ntct_LondonInterbankOfferedRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=ntct_SwingLineLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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LONG-TERM DEBT - Narrative (Details) (USD $)	0 Months Ended	9 Months Ended
LONG-TERM DEBT - Narrative (Details) (USD $)	Nov. 22, 2011	Dec. 31, 2014
Debt Instrument [Line Items]
Revolving credit facility outstanding amount	$ 250,000,000	$ 0
Increase in revolving credit facility outstanding amount	300,000,000
Term for increase in revolving credit facility before maturity date, days	90 days
Line of credit facility, maturity	Nov. 21, 2016
Percentage of capital stock of foreign subsidiaries used as guarantee		65.00%
Federal funds effective rate
Debt Instrument [Line Items]
Interest rate in excess of effective rate	0.50%
LIBOR
Debt Instrument [Line Items]
Margin over applicable interest rate	1.00%
Maximum
Debt Instrument [Line Items]
Leverage ratio	1.00
Maximum \| Base rate loans
Debt Instrument [Line Items]
Margin over applicable interest rate	1.00%
Maximum \| Eurodollar rate loans
Debt Instrument [Line Items]
Margin over applicable interest rate	2.00%
Minimum
Debt Instrument [Line Items]
Leverage ratio	2.50
Minimum \| Base rate loans
Debt Instrument [Line Items]
Margin over applicable interest rate	0.25%
Minimum \| Eurodollar rate loans
Debt Instrument [Line Items]
Margin over applicable interest rate	1.25%
Swing line loan sub-facility \| Maximum
Debt Instrument [Line Items]
Revolving credit facility outstanding amount	10,000,000
Letter of credit sub-facility \| Maximum
Debt Instrument [Line Items]
Revolving credit facility outstanding amount	$ 10,000,000