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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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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Apr. 01, 2018	Mar. 31, 2018
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	$ 27,429		$ 27,429		$ 38,128	$ 33,502
Related party accounts payable	22,102		22,102			30,133
Total cost of revenue	63,980	$ 74,243	126,007	$ 140,805
Research and development expenses	55,959	58,509	111,422	117,475
Sales and marketing	72,051	77,266	150,183	162,627
General and administrative expenses	25,294	29,495	51,353	59,367
Cash flows, due from related party			(1,719)	(554)
Cash flows, due to related party			(3)	168
Product
Related Party Transaction [Line Items]
Total cost of revenue	34,492	44,371	67,457	80,833
Service
Related Party Transaction [Line Items]
Total cost of revenue	29,488	29,872	58,550	59,972
Affiliated Entity
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	1,468		1,468			3,187
Related party accounts payable	366		366			369
Research and development expenses	0	0	2	3
Sales and marketing	0	0	0	2
General and administrative expenses	2	700	15	944
Cash flows, due from related party			1,719	554
Cash flows, due to related party			(3)	168
Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	0	0	0	245
Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	146	259	320	288
Danaher \| Affiliated Entity
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	0		0			252
Related party accounts payable	0		0			0
Research and development expenses	0	0	0	0
Sales and marketing	0	0	0	2
General and administrative expenses	0	3	0	4
Related party transaction	0	3	0	6
Cash flows, due from related party			252	154
Cash flows, due to related party			0	0
Danaher \| Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	0	0	0	0
Danaher \| Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	0	0	0	0
Fortive \| Affiliated Entity
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	1,468		1,468			2,935
Related party accounts payable	366		366			$ 369
Research and development expenses	0	0	2	3
Sales and marketing	0	0	0	0
General and administrative expenses	2	697	15	940
Related party transaction	148	956	337	1,476
Cash flows, due from related party			1,467	400
Cash flows, due to related party			(3)	168
Fortive \| Affiliated Entity \| Product
Related Party Transaction [Line Items]
Total cost of revenue	0	0	0	245
Fortive \| Affiliated Entity \| Service
Related Party Transaction [Line Items]
Total cost of revenue	$ 146	$ 259	$ 320	$ 288