Consolidated Balance Sheets - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 87,559,000	$ 41,026,000
Marketable Securities, Current	211,331,000	248,140,000
Accounts receivable, net of allowance of $702 and $769 at December 31, 2016 and 2015, respectively	78,034,000	75,825,000
Prepaid expenses and other current assets	18,692,000	13,974,000
Total current assets	395,616,000	378,965,000
Marketable Securities, Noncurrent	119,508,000	76,710,000
Property and equipment, net	60,579,000	61,442,000
Deferred tax assets, net	18,830,000	26,387,000
Intangible assets, net	16,795,000	21,976,000
Goodwill	7,447,000	7,225,000
Restricted cash	1,200,000	1,200,000
Other noncurrent assets	15,082,000	11,775,000
Total assets	675,608,000	585,680,000
Operating Lease, Right-of-Use Asset	40,551,000	0
Current liabilities:
Accounts payable	848,000	5,588,000
Accrued liabilities	22,784,000	26,695,000
Total current liabilities	223,467,000	196,907,000
Contract with Customer, Liability, Noncurrent	20,935,000	20,423,000
Other noncurrent liabilities	388,000	10,361,000
Commitments and contingencies (Note 6)
Operating Lease, Liability, Noncurrent	44,015,000	0
Total liabilities	288,805,000	227,691,000
Stockholders’ equity:
Preferred stock: $0.001 par value; 20,000,000 shares authorized, no shares issued and outstanding at December 31, 2016 and 2015	0	0
Common stock, $0.001 par value; 1,000,000,000 shares authorized, 35,841,001 and 34,414,631 shares issued and outstanding at December 31, 2016 and 2015, respectively	39,000	39,000
Additional paid-in capital	362,408,000	330,572,000
Accumulated other comprehensive loss	1,162,000	(586,000)
Accumulated deficit	23,194,000	27,964,000
Total stockholders’ equity	386,803,000	357,989,000
Total liabilities and stockholders’ equity	675,608,000	585,680,000
Contract with Customer, Liability, Current	$ 192,172,000	$ 164,624,000