Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current assets:
Cash and cash equivalents	$ 42,975	$ 39,040
Short-term marketable securities	319,274	190,908
Accounts receivable, net	70,010	54,055
Inventories	50,204	34,931
Prepaid expenses and other current assets	11,808	8,024
Total current assets	494,271	326,958
Long-term marketable securities	37,502	47,143
Property and equipment, net	117,167	87,777
Goodwill	35,808	31,045
In-process research and development	16,705	14,482
Long-term deferred tax assets, net	70,746	34,723
Other assets	14,176	8,286
Total assets	786,375	550,414
Current liabilities:
Accounts payable	23,565	20,620
Accrued expenses and other liabilities	46,147	37,703
Deferred revenue	14,970	10,495
Current portion of capital lease obligation		799
Total current liabilities	84,682	69,617
Other long-term liabilities	776	3,251
Contingent consideration	10,490	9,153
Long-term deferred tax liabilities	903	783
Capital lease obligation, net of current portion		15,539
Total liabilities	96,851	98,343
Commitments and contingencies (Note 11)
Stockholders' equity:
Class B Preferred Stock, $.01 par value Authorized - 1,000,000 shares; Issued and outstanding - none
Common stock, $.01 par value Authorized - 100,000,000 shares; Issued - 46,100,649 shares at March 31, 2018 and 45,249,281 shares at March 31, 2017; Outstanding - 44,375,337 shares at March 31, 2018 and 43,673,286 shares at March 31, 2017	444	437
Additional paid in capital	619,905	565,962
Retained earnings (Accumulated deficit)	140,457	(46,959)
Treasury stock at cost - 1,725,312 shares at March 31, 2018 and 1,575,995 shares at March 31, 2017	(67,078)	(46,763)
Accumulated other comprehensive loss	(4,204)	(20,606)
Total stockholders' equity	689,524	452,071
Total liabilities and stockholders' equity	$ 786,375	$ 550,414