Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0001393434 (http://www.sec.gov/CIK)

Statement of Financial Position [Abstract]	Period [Axis]
	2016-12-31	2015-12-31
Statement of Financial Position [Abstract]
Assets
Current assets:
Cash and cash equivalents	32,936,000	30,784,000
Marketable securities	35,209,000	74,280,000
Accounts receivable	250,000	193,000
Inventory	113,000	134,000
Prepaid expenses and other current assets	1,390,000	1,592,000
Total current assets	69,898,000	106,983,000
Property and equipment, net	3,313,000	3,095,000
Restricted cash	1,728,000	228,000
Total assets	74,939,000	110,306,000
Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable	2,116,000	1,957,000
Accrued expenses and deferred rent	4,635,000	3,379,000
Deferred revenue		42,000
Notes payable, net of discount, current	1,549,000
Total current liabilities	8,300,000	5,378,000
Deferred rent, long-term	537,000	68,000
Notes payable, net of discount, long-term	14,094,000	15,272,000
Total liabilities	22,931,000	20,718,000
Commitments and contingencies (Note 13)	xsi:nil	xsi:nil
Stockholders' equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized at December 31, 2016 and 2015; no shares issued or outstanding at December 31, 2016 and 2015	xsi:nil	xsi:nil
Common stock, $0.0001 par value; 100,000,000 shares authorized at December 31, 2016 and 2015; 25,024,100 and 24,750,281 shares issued and outstanding at December 31, 2016 and 2015, respectively	3,000	2,000
Additional paid-in capital	225,889,000	218,830,000
Accumulated deficit	(173,879,000)	(129,176,000)
Accumulated other comprehensive income (loss)	(5,000)	(68,000)
Total stockholders' equity	52,008,000	89,588,000
Total liabilities and stockholders' equity	74,939,000	110,306,000