RELATED PARTY TRANSACTIONS - Schedule of Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Apr. 01, 2018
Related Party Transaction [Line Items]
Related party prepaid expenses and other current assets	$ 35,658	$ 33,502		$ 38,128
Related party accounts payable	24,582	30,133
Total cost of revenue	254,127	271,905	$ 346,139
Related party research and development	203,588	215,076	232,701
Related party selling and marketing	291,870	312,536	328,628
Related party general and administrative expense	93,572	109,479	118,438
Related party other expense (income)	434	3,776	1,716
Due from related party, operating activities	(172)	(443)	(25,055)
Due to related party	234	(75)	(2,792)
Service
Related Party Transaction [Line Items]
Total cost of revenue	113,189	113,277	112,864
Product
Related Party Transaction [Line Items]
Total cost of revenue	140,938	158,628	233,275
Affiliated Entity
Related Party Transaction [Line Items]
Related party prepaid expenses and other current assets	335	3,187
Related party accounts payable	244	369
Related party research and development	20	3	1,624
Related party selling and marketing	0	2	2,423
Related party general and administrative expense	20	1,703	4,099
Related party other expense (income)	0	(56)	(426)
Due from related party, operating activities	172	443	25,055
Due to related party	234	(75)	(2,792)
Due from related party, investing activities	0	0	12,864
Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	529	665	745
Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	0	245	7,229
Danaher \| Affiliated Entity
Related Party Transaction [Line Items]
Related party prepaid expenses and other current assets	0	252
Related party research and development	0	0	1,720
Related party selling and marketing	0	2	2,273
Related party general and administrative expense	0	7	2,551
Related party transaction amount	0	9	11,719
Due from related party, operating activities	58	96	17,310
Due to related party	243	0	(2,954)
Due from related party, investing activities	0	0	12,864
Danaher \| Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	0	0	485
Danaher \| Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	0	0	4,690
Fortive \| Affiliated Entity
Related Party Transaction [Line Items]
Related party prepaid expenses and other current assets	335	2,935
Related party accounts payable	244	369
Related party research and development	20	3	(96)
Related party selling and marketing	0	0	150
Related party general and administrative expense	20	1,696	1,548
Related party other expense (income)	0	(56)	(426)
Related party transaction amount	569	2,553	3,975
Due from related party, operating activities	114	347	7,745
Due to related party	(9)	(75)	162
Fortive \| Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	529	665	260
Fortive \| Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	$ 0	$ 245	$ 2,539

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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