Consolidated Statements Of Comprehensive Loss - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements Of Comprehensive Loss [Abstract]
Revenue	$ 4,064,187	$ 10,780
Cost of sales	(341,979)	(12,219)
Gross margin	3,722,208	(1,439)
Research and development expenses	3,343,327	4,137,709	$ 7,046,772
Selling, general and administrative expenses	16,317,724	12,924,982	16,620,206
Total operating expenses	19,661,051	17,062,691	23,666,978
Interest and other income	17,834	10,862	104,943
Interest expense	(67,904)	(21,739)	(6,920)
Change in fair value of contingent payment obligation (Note 8)	(4,860,357)
Total interest and other	(4,910,427)	(10,877)	98,023
Net loss before income taxes	(20,849,270)	(17,075,007)	(23,568,955)
Foreign income tax expense	(660,000)
Net loss	(21,509,270)	(17,075,007)	(23,568,955)
Other comprehensive (loss) income, net of tax:
Unrealized (loss) gain on available-for-sale securities	124	(53)	8,215
Other comprehensive income (loss), net of tax	124	(53)	8,215
Comprehensive loss	$ (21,509,146)	$ (17,075,060)	$ (23,560,740)
Basic and diluted net loss per common share	$ (1.76)	$ (1.74)	$ (2.45)
Weighted average common shares outstanding	12,244,254	9,842,334	9,622,595