CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 89,475	$ 102,176
Marketable securities	430,746	305,488
Accounts receivable	33,025	44,039
Unbilled receivables	141,341	184,366
Inventories	14,218	10,086
Prepaids and other current assets	16,229	18,524
Total current assets	725,034	664,679
Intangible assets, net	41,052	54,900
Goodwill	183,222	183,465
Property, plant and equipment, net	59,425	44,714
Operating lease right-of-use assets	29,961	37,020
Deferred tax assets	5,249	4,574
Unbilled receivables, long-term	260,404	343,703
Other assets	4,671	5,931
Total assets	1,309,018	1,338,986
Current liabilities:
Accounts payable	13,323	9,549
Accrued salaries and benefits	15,719	20,291
Deferred revenue	14,950	11,947
Income taxes payable	20,008	19,142
Operating lease liabilities	4,576	6,357
Other current liabilities	22,306	18,893
Total current liabilities	90,882	86,179
Convertible notes	154,182	148,788
Long-term operating lease liabilities	35,973	39,889
Long-term income taxes payable	45,882	60,094
Deferred tax liabilities	15,139	13,846
Other long-term liabilities	8,714	19,272
Total liabilities	350,772	368,068
Commitments and contingencies (Notes 9, 11 and 15)
Stockholders’ equity:
Convertible preferred stock, $.001 par value: Authorized: 5,000,000 shares; Issued and outstanding: no shares at September 30, 2020 and December 31, 2019	0	0
Common stock, $.001 par value: Authorized: 500,000,000 shares; Issued and outstanding: 113,922,520 shares at September 30, 2020 and 112,131,352 shares at December 31, 2019	114	112
Additional paid-in capital	1,280,051	1,261,142
Accumulated deficit	(321,787)	(290,244)
Accumulated other comprehensive loss	(132)	(92)
Total stockholders’ equity	958,246	970,918
Total liabilities and stockholders’ equity	$ 1,309,018	$ 1,338,986