Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 87,482	$ 67,192
Accounts receivable and unbilled receivables, net of allowances of $3,698 and $2,582, respectively	205,353	196,238
Inventories	103,906	100,868
Prepaid expenses	19,679	20,700
Other current assets	13,419	12,136
Total current assets	429,839	397,134
Property and equipment, net	52,847	51,500
Long-term investment in sales-type leases, net	21,041	17,082
Operating lease right-of-use assets	61,482	0
Goodwill	335,699	335,887
Intangible assets, net	134,101	143,686
Long-term deferred tax assets	31,195	15,197
Prepaid commissions	44,607	46,143
Other long-term assets	86,167	74,613
Total assets	1,196,978	1,081,242
Current liabilities:
Accounts payable	40,183	38,038
Accrued compensation	33,619	41,660
Accrued liabilities	54,570	43,047
Deferred revenues, net	83,012	81,835
Total current liabilities	211,384	204,580
Long-term deferred revenues	9,658	10,582
Long-term deferred tax liabilities	61,292	41,484
Long-term operating lease liabilities	55,237	0
Other long-term liabilities	9,603	9,562
Long-term debt, net	76,562	135,417
Total liabilities	423,736	401,625
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; 50,784 and 49,480 shares issued; 41,639 and 40,335 shares outstanding, respectively	51	50
Treasury stock at cost, 9,145 shares outstanding, respectively	(185,074)	(185,074)
Additional paid-in capital	753,127	678,041
Retained earnings	216,714	197,454
Accumulated other comprehensive loss	(11,576)	(10,854)
Total stockholders’ equity	773,242	679,617
Total liabilities and stockholders’ equity	$ 1,196,978	$ 1,081,242