COMMITMENTS AND CONTINGENCIES	6 Months Ended
Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Acquisition related – The Company has a contingent liability related to the acquisition of Simena in November 2011 for future consideration to be paid to the seller which had an initial fair value of $8.0 million at the time of acquisition. At September 30, 2017, the present value of the future consideration was $4.9 million. The Company has a contingent liability for $523 thousand related to the acquisition of Efflux in July 2017 for which an escrow account was established to cover damages NetScout suffers related to any liabilities that NetScout did not agree to assume or as a result of the breach of representations and warranties of the seller as described in the merger agreement. Generally, indemnification claims that Efflux would be liable for are limited to the total amount of the escrow account and shall be the sole source for the satisfaction of any damages to the Company for such claims, but such limitation does not apply with respect to seller's breach of certain fundamental representations or related to other specified indemnity items, for which certain of Efflux's shareholders may be liable for additional amounts in excess of the escrow amount. Except to the extent that valid indemnification claims are made prior to such time, the $523 thousand will be paid to the seller on July 12, 2018. In addition, the Company had a contingent liability at March 31, 2017 for $660 thousand related to the acquisition of Avvasi in August 2016. The $660 thousand was paid to the seller in August 2017. Legal – From time to time, NetScout is subject to legal proceedings and claims in the ordinary course of business. In the opinion of management, the amount of ultimate expense with respect to any current legal proceedings and claims, if determined adversely, will not have a material adverse effect on the Company’s financial condition, results of operations or cash flows. As disclosed in Part II, Item 1, in March 2016, Packet Intelligence LLC (“Packet Intelligence” or “Plaintiff”) filed a Complaint against NetScout and two subsidiary entities in the United States District Court for the Eastern District of Texas asserting infringement of five United States patents. Plaintiff’s Complaint alleged that legacy Tektronix GeoProbe products, including the G10 and GeoBlade products, infringed these patents. NetScout filed an Answer denying Plaintiff’s allegations and asserting that Plaintiff’s patents were, among other things, invalid, not infringed, and unenforceable due to inequitable conduct. In September 2017, the Court dismissed Plaintiff’s claims and NetScout’s counterclaims with respect to two of the five patents. In October 2017, a jury trial was held to address the parties’ claims and counterclaims regarding infringement of the remaining three patents by the G10 and GeoBlade products, invalidity of these patents, and damages. On October 13, 2017, the jury rendered a verdict finding in favor of the Plaintiff and that Plaintiff was entitled to $3,500,000 for pre-suit damages and $2,250,000 for post-suit damages. The jury indicated that the awarded damages amounts were intended to reflect a running royalty. The Court also conducted a bench trial on whether these patents were unenforceable due to, among other things, inequitable conduct. The Court has not yet rendered a decision on the equitable issues or entered final judgment in this matter, and the deadline for the parties to file any post-trial motions challenging the jury’s verdict or concerning the other legal and equitable defenses raised by NetScout has not yet passed. NetScout has concluded that the risk of loss from this matter is currently neither remote nor probable. NetScout intends to continue to vigorously dispute Packet Intelligence’s claims.

COMMITMENTS AND CONTINGENCIES

Acquisition related – The Company has a contingent liability related to the acquisition of Simena in November 2011 for future consideration to be paid to the seller which had an initial fair value of $8.0 million at the time of acquisition. At September 30, 2017, the present value of the future consideration was $4.9 million.

The Company has a contingent liability for $523 thousand related to the acquisition of Efflux in July 2017 for which an escrow account was established to cover damages NetScout suffers related to any liabilities that NetScout did not agree to assume or as a result of the breach of representations and warranties of the seller as described in the merger agreement. Generally, indemnification claims that Efflux would be liable for are limited to the total amount of the escrow account and shall be the sole source for the satisfaction of any damages to the Company for such claims, but such limitation does not apply with respect to seller's breach of certain fundamental representations or related to other specified indemnity items, for which certain of Efflux's shareholders may be liable for additional amounts in excess of the escrow amount. Except to the extent that valid indemnification claims are made prior to such time, the $523 thousand will be paid to the seller on July 12, 2018.

In addition, the Company had a contingent liability at March 31, 2017 for $660 thousand related to the acquisition of Avvasi in August 2016. The $660 thousand was paid to the seller in August 2017.

Legal – From time to time, NetScout is subject to legal proceedings and claims in the ordinary course of business. In the opinion of management, the amount of ultimate expense with respect to any current legal proceedings and claims, if determined adversely, will not have a material adverse effect on the Company’s financial condition, results of operations or cash flows.

As disclosed in Part II, Item 1, in March 2016, Packet Intelligence LLC (“Packet Intelligence” or “Plaintiff”) filed a Complaint against NetScout and two subsidiary entities in the United States District Court for the Eastern District of Texas asserting infringement of five United States patents. Plaintiff’s Complaint alleged that legacy Tektronix GeoProbe products, including the G10 and GeoBlade products, infringed these patents. NetScout filed an Answer denying Plaintiff’s allegations and asserting that Plaintiff’s patents were, among other things, invalid, not infringed, and unenforceable due to inequitable conduct. In September 2017, the Court dismissed Plaintiff’s claims and NetScout’s counterclaims with respect to two of the five patents. In October 2017, a jury trial was held to address the parties’ claims and counterclaims regarding infringement of the remaining three patents by the G10 and GeoBlade products, invalidity of these patents, and damages. On October 13, 2017, the jury rendered a verdict finding in favor of the Plaintiff and that Plaintiff was entitled to $3,500,000 for pre-suit damages and $2,250,000 for post-suit damages. The jury indicated that the awarded damages amounts were intended to reflect a running royalty. The Court also conducted a bench trial on whether these patents were unenforceable due to, among other things, inequitable conduct. The Court has not yet rendered a decision on the equitable issues or entered final judgment in this matter, and the deadline for the parties to file any post-trial motions challenging the jury’s verdict or concerning the other legal and equitable defenses raised by NetScout has not yet passed. NetScout has concluded that the risk of loss from this matter is currently neither remote nor probable. NetScout intends to continue to vigorously dispute Packet Intelligence’s claims.