Business Acquisition, Equity Interest Issued or Issuable, Contingent Multiplier

No definition available.

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

- Definition

Percent of equity interests of the acquirer issued when equity, including instruments or interests are issued or issuable in consideration for the business combination.

+ References

No definition available.

+ Details

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

- Definition

Percent of equity interests of the acquirer retained when equity, including instruments or interests are issued or issuable in consideration for the business combination.

+ References

No definition available.

+ Details

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

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

+ Details

Name:	us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=ntct_PotomacHoldingLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ContingentConsiderationByTypeAxis=ntct_MergerAgreementTerminationFeeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

PROPOSED ACQUISITION - Narrative (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	6 Months Ended
	Dec. 31, 2014	Sep. 30, 2015
Newco
Business Acquisition [Line Items]
Acquisition related costs	$ 6.2
Merger agreement termination fee \| Newco
Business Acquisition [Line Items]
Contract termination fee	55
Scenario, forecast
Business Acquisition [Line Items]
Ownership percentage		40.50%
Scenario, forecast \| Newco
Business Acquisition [Line Items]
Percentage of common stock outstanding		59.50%
Scenario, forecast \| Common stock \| Newco
Business Acquisition [Line Items]
Shares issued in business acquisition (in shares)		62.5
Common stock conversion multiplier		1.46
Scenario, forecast \| RBC capital markets
Business Acquisition [Line Items]
Acquisition related costs		11.0
Scenario, forecast \| Consummation of mergers \| RBC capital markets
Business Acquisition [Line Items]
Acquisition related costs		9.5