Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 104,080	$ 127,210
Accounts receivable and unbilled receivables, net of allowances of $3,869 and $3,227, respectively	233,068	218,362
Inventories	112,785	108,011
Prepaid expenses	14,155	14,478
Other current assets	14,235	15,177
Total current assets	478,323	483,238
Property and equipment, net	52,997	54,246
Long-term investment in sales-type leases, net	19,992	19,750
Operating lease right-of-use assets	54,376	56,130
Goodwill	334,842	336,539
Intangible assets, net	120,063	124,867
Long-term deferred tax assets	14,142	14,142
Prepaid commissions	45,981	48,862
Other long-term assets	110,931	103,036
Total assets	1,231,647	1,240,810
Current liabilities:
Accounts payable	46,788	46,380
Accrued compensation	34,990	44,155
Accrued Liabilities, Current	58,060	55,567
Deferred revenues, net	108,602	90,894
Total current liabilities	248,440	236,996
Long-term deferred revenues	6,019	7,083
Long-term deferred tax liabilities	37,810	39,090
Long-term operating lease liabilities	48,851	50,669
Other long-term liabilities	12,027	11,718
Long-term debt	0	50,000
Total liabilities	353,147	395,556
Commitments and contingencies (Note 11)
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; 51,751 and 51,277 shares issued; 42,606 and 42,132 shares outstanding, respectively	52	51
Treasury stock at cost, 9,145 shares outstanding, respectively	(185,074)	(185,074)
Additional paid-in capital	807,823	780,931
Retained earnings	269,839	258,792
Accumulated other comprehensive loss	(14,140)	(9,446)
Total stockholders’ equity	878,500	845,254
Total liabilities and stockholders’ equity	$ 1,231,647	$ 1,240,810