SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	3 Months Ended								12 Months Ended			36 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2018 USD ($) Segment reporting_unit $ / shares	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2018 USD ($) company	Apr. 01, 2018 USD ($)	Jul. 12, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of reportable segments | Segment									1
Unrecognized accounts receivable and deferred revenue	$ 20,000,000				$ 17,900,000				$ 20,000,000	$ 17,900,000		$ 20,000,000
Number of reporting units | reporting_unit									2
Number of companies acquired | company												3
Fair value of contingent liability	5,464,000				5,449,000				$ 5,464,000	5,449,000		$ 5,464,000
Amortization included as cost of product									1,000,000	594,000	$ 0
Capitalized software development costs	100,000				1,400,000				100,000	1,400,000		100,000
Foreign currency losses									4,100,000	2,500,000	1,500,000
Advertising expense									6,500,000	8,100,000	6,400,000
Net income (loss)	16,817,000	$ 89,685,000	$ (2,468,000)	$ (24,222,000)	22,310,000	$ 21,245,000	$ (1,266,000)	$ (8,998,000)	79,812,000	33,291,000	(28,369,000)
Net cash provided by (used in) operating activities									222,454,000	226,764,000	97,211,000
Net cash provided by (used in) financing activities									$ (220,962,000)	(89,553,000)	(17,226,000)
Computer equipment and internal use software
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life									3 years
Efflux Systems, Inc.
Summary Of Significant Accounting Policies [Line Items]
Fair value of contingent liability	523,000								$ 523,000			523,000		$ 523,000
Avvasi
Summary Of Significant Accounting Policies [Line Items]
Fair value of contingent liability					$ 660,000					660,000
Customer Concentration Risk | Accounts Receivable | Danaher
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 3,200,000								3,200,000			$ 3,200,000
Accounting Standards Update 2016-09
Summary Of Significant Accounting Policies [Line Items]
Share-based compensation excess tax benefit amount									700,000
Net income (loss)									$ 700,000
Earnings per share, basic and diluted (in USD per share) | $ / shares									$ 0.01
Excess tax benefit from share-based compensation, operating activities									$ 700,000	1,000,000	1,900,000
Net cash provided by (used in) operating activities									700,000	(1,000,000)	1,900,000
Net cash provided by (used in) financing activities									$ (700,000)	$ 1,000,000	$ (1,900,000)
Subsequent Event | Accounting Standards Update 2014-09
Summary Of Significant Accounting Policies [Line Items]
Release of deferred revenue													$ 34,900,000
Capitalized commissions costs													$ 7,200,000