Fixed Charge Coverage Ratio

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Balance Type:	na
Period Type:	instant

- Definition

Leverage Ratio

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage Of Annual Excess Cash Flow To Be Used For Prepayment Of Credit Facility

+ Details

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Period Type:	duration

- Definition

Percentage of Net Proceeds From Issuance of Debt To Be Used For Prepayment Of Line Of Credit

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of Net Proceeds From Issuance of Equity To Be Used For Prepayment Of Line Of Credit

+ Details

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Namespace Prefix:	ntct
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Balance Type:	na
Period Type:	duration

- Definition

Percentage of Net Proceeds From Issuance Recovery and Condemnation Events To Be Used For Prepayment Of Line Of Credit

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of Net Proceeds From Sale of Asset To Be Used For Prepayment Of Line Of Credit

+ Details

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Namespace Prefix:	ntct
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Balance Type:	na
Period Type:	duration

- Definition

Spread Over Interest Rate

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- 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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

Reference 3: 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

+ Details

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- 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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 19
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Period Type:	duration

Long-term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			1 Months Ended					3 Months Ended			3 Months Ended
	Jun. 30, 2011	Jun. 30, 2011 Maximum [Member] Financial Covenants [Member]	Jun. 30, 2011 Minimum [Member] Financial Covenants [Member]	Dec. 31, 2007 Term Loan [Member]	Jun. 30, 2011 Term Loan [Member]	Jun. 30, 2010 Term Loan [Member]	Jun. 30, 2011 Revolving Credit Facility [Member]	Dec. 31, 2007 Revolving Credit Facility [Member]	Jun. 30, 2011 Maximum [Member]	Jun. 30, 2011 Maximum [Member] Alternative Base Rate Loans [Member]	Jun. 30, 2011 Maximum [Member] Eurodollar Rate Loans [Member]	Jun. 30, 2011 Minimum [Member]	Jun. 30, 2011 Minimum [Member] Alternative Base Rate Loans [Member]	Jun. 30, 2011 Minimum [Member] Eurodollar Rate Loans [Member]
Credit facility maximum borrowing capacity				$ 100				$ 10
Proceeds from term loan				100
Credit facility outstanding amount							$ 0
Credit agreement interest term	(1) a rate per annum equal to the greater of KeyBank's prime rate or 0.5% in excess of the federal funds effective rate, or the Alternative Base Rate, or (2) the one-, two-, three-, or six-month per annum LIBOR, as selected by the Company, multiplied by the statutory reserve adjustment, collectively the Eurodollar Rate, in each case plus an applicable margin.
Margin over applicable interest rate (basis point)										75	200		175	300
Interest rate at period end					2.50%	2.688%
Leverage ratio		3.00							1.00			2.50
Fixed charge coverage ratio			1.25
Percentage of net proceeds from sale of asset to be used for prepayment of credit facility	100.00%
Percentage of net proceeds from issuance of debt to be used for prepayment of credit facility	100.00%
Percentage of annual excess cash flow to be used for prepayment of credit facility									50.00%			25.00%
Percentage of net proceeds from issuance of equity to be used for prepayment of credit facility	50.00%
Percentage of net proceeds from issuance recovery and condemnation events to be used for prepayment of credit facility	100.00%