STOCK PLANS (Tables)

12 Months Ended

Mar. 31, 2020

Share-based Payment Arrangement [Abstract]

Summary of Share-Based Compensation Expense

The following is a summary of share-based compensation expense including restricted stock units and employee stock purchases made under the Company's employee stock purchase plan (ESPP) based on estimated fair values within the applicable cost and expense lines identified below (in thousands):

	Year Ended March 31,
	2020		2019		2018
Cost of product revenue	$	1,069	$	1,463	$	1,159
Cost of service revenue	5,774		5,959		4,824
Research and development	15,511		17,321		14,711
Sales and marketing	17,085		18,923		15,213
General and administrative	11,422		12,662		11,410
	$	50,861	$	56,328	$	47,317

Summary of Transactions under Amended 2007 and 2019 Equity Incentive Plan

Transactions under the Amended 2007 and 2019 Plan during the fiscal years ended March 31, 2020, 2019 and 2018 are summarized in the table below.

	Restricted Stock Units
	Number of Awards	Weighted Average Fair Value
Outstanding – March 31, 2017	3,610,301	$	30.24
Granted	1,962,590	34.01
Vested	(1,216,585)	31.09
Canceled	(277,526)	31.70
Outstanding – March 31, 2018	4,078,780	$	31.77
Granted	2,178,339	30.10
Vested	(1,438,219)	32.49
Canceled	(608,245)	30.52
Outstanding – March 31, 2019	4,210,655	$	30.84
Granted	2,062,110	26.32
Vested	(1,651,284)	31.03
Canceled	(347,008)	29.74
Outstanding – March 31, 2020	4,274,473	$	28.68

Schedule of Aggregate Intrinsic Values of Stock Options and Restricted Stock Units

The aggregate intrinsic value of stock options exercised and the fair value of restricted stock units vested at March 31, 2020, 2019 and 2018 were as follows (in thousands):

	Year Ended March 31,
	2020		2019		2018
Total fair value of restricted stock unit awards vested	$	37,783	$	38,070	$	40,539