Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents		$ 174,653	$ 140,544
Short-term marketable securities		370,974	278,417
Accounts receivable		40,363	35,690
Inventory		14,176	9,136
Prepaid expenses and other current assets		4,082	5,204
Total current assets		604,248	468,991
Long-term marketable securities		277,301	77,563
Property and equipment, net		34,811	31,003
Intangible assets		8,987	0
Goodwill			0
Capitalized license fees		7,313	7,800
Deferred tax assets		1,235	0
Other assets		3,159	2,046
Total Assets	[1]	939,989	587,403
Current liabilities:
Accounts payable		15,700	10,642
Accrued compensation		13,687	12,986
Accrued expenses		11,092	7,081
Capital lease, current		74	97
Deferred revenue		16,496	16,138
Total current liabilities		57,049	46,944
Capital lease, net of current portion		80	119
Deferred rent, net of current portion		10,912	7,844
Obligation related to royalty		7,136	7,338
Deferred tax liabilities		1,235	0
Other long-term liabilities		1,303	206
Total Liabilities	[1]	77,715	62,451
Commitments and contingencies (Note 8)
Redeemable noncontrolling interest		46,800	41,800
Stockholders’ equity:
Common stock, par value of $0.00001 per share; 350,000,000 shares authorized as of June 30, 2019 and December 31, 2018; 92,806,252 and 85,832,454 shares issued and outstanding as of June 30, 2019 and December 31, 2018, respectively		1	1
Additional paid-in capital		1,128,938	764,033
Accumulated other comprehensive loss		1,344	(83)
Accumulated deficit		(314,809)	(280,799)
Total Stockholders’ Equity		815,474	483,152
Total Liabilities, Redeemable Noncontrolling Interest and Stockholders’ Equity		$ 939,989	$ 587,403

[1] As of June 30, 2019 and December 31, 2018, includes $45.1 million and $48.3 million of assets, respectively, that can be used only to settle obligations of the consolidated variable interest entity (“VIE”) and VIE’s subsidiaries, and $984,000 and $1.2 million of liabilities of the consolidated VIE and VIE’s subsidiaries, respectively, for which their creditors do not have recourse to the general credit of the Company. See Note 3.