Condensed Consolidated Balance Sheets (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 629,171	$ 127,210
Accounts receivable and unbilled receivables, net of allowances of $3,839 and $3,227, respectively	188,102	218,362
Inventories	103,101	108,011
Prepaid expenses	20,399	14,478
Other current assets	22,631	15,177
Total current assets	963,404	483,238
Property and equipment, net	57,559	54,246
Long-term investment in sales-type leases, net	22,510	19,750
Operating lease right-of-use assets	50,415	56,130
Goodwill	336,456	336,539
Intangible assets, net	111,587	124,867
Long-term deferred tax assets	14,985	14,142
Prepaid commissions	46,649	48,862
Other long-term assets	115,712	103,036
Total assets	1,719,277	1,240,810
Current liabilities:
Accounts payable	37,203	46,380
Accrued compensation	35,778	44,155
Accrued liabilities	59,254	55,567
Deferred revenues, net	101,641	90,894
Total current liabilities	233,876	236,996
Long-term deferred revenues	5,163	7,083
Long-term deferred tax liabilities	35,584	39,090
Long-term operating lease liabilities	44,365	50,669
Other long-term liabilities	19,775	11,718
Revolving credit facility	0	50,000
Convertible senior notes, net	462,115	0
Total liabilities	800,878	395,556
Commitments and contingencies (Note 12)
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000 shares authorized; no shares issued	0	0
Common stock, $0.001 par value, 100,000 shares authorized; 52,168 and 51,277 shares issued; 42,274 and 42,132 shares outstanding, respectively	52	51
Treasury stock at cost, 9,894 and 9,145 shares outstanding, respectively	(238,109)	(185,074)
Additional paid-in capital	892,290	780,931
Retained earnings	274,345	258,792
Accumulated other comprehensive loss	(10,179)	(9,446)
Total stockholders’ equity	918,399	845,254
Total liabilities and stockholders’ equity	$ 1,719,277	$ 1,240,810
Treasury stock, shares (in shares)	9,894	9,145