Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Shelf Offering [Member] Common Stock [Member]	Shelf Offering [Member] Additional Paid-in Capital [Member]	Shelf Offering [Member]	Pioneer Pharma Co. [Member] Additional Paid-in Capital [Member]	Pioneer Pharma Co. [Member]	Employee [Member] Common Stock [Member]	Employee [Member] Additional Paid-in Capital [Member]	Employee [Member]	Nonemployees [Member] Common Stock [Member]	Nonemployees [Member] Additional Paid-in Capital [Member]	Nonemployees [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2013												1,785,000
Balance at Dec. 31, 2013												$ 18	$ 64,866	$ (15)	$ (56,353)	$ 8,516
Net loss															(15,194)	(15,194)
Change in unrealized gains (losses) on investments														$ 15		$ 15
Issuance of common stock (in shares)	275,000
Issuance of common stock	$ 3	$ 7,122	$ 7,125	$ 205	$ 205
Issuance of stock for option exercises (in shares)												2,000				2,000
Issuance of stock for option exercises													34			$ 34
Issuance of stock to consultants for services (in shares)												2,000
Issuance of stock to consultants for services													28			28
Employee bonus paid in common stock (in shares)												1,000
Employee bonus paid in common stock													77			77
Stock-based compensation expense related to employee and director stock options													853			853
Stock-based compensation expense related to non-employee stock options													189			189
Vesting of employee restricted stock awards (in shares)												1,000
Balance (in shares) at Dec. 31, 2014												2,066,000
Balance at Dec. 31, 2014												$ 21	73,374		(71,547)	1,848
Net loss															(18,973)	(18,973)
Issuance of common stock (in shares)	85,000											4,000
Issuance of common stock	$ 1	1,176	1,177
Issuance of stock to consultants for services													63			63
Employee bonus paid in common stock (in shares)												3,000
Employee bonus paid in common stock													62			62
Stock-based compensation expense related to employee and director stock options													1,194			1,194
Stock-based compensation expense related to non-employee stock options													188			188
Balance (in shares) at Dec. 31, 2015												3,486,000
Balance at Dec. 31, 2015												$ 35	85,387		(90,520)	(5,098)
Issuance of stock and warrants, net of offering costs (in shares)												1,328,000
Issuance of stock and warrants, net offering costs												$ 13	11,505			11,518
Equity transferred to warrant liability													(2,175)			(2,175)
Net loss															(13,151)	$ (13,151)
Issuance of common stock (in shares)	7,692,000											2,000
Issuance of common stock	$ 77	$ 13,571	$ 13,648
Issuance of stock for option exercises (in shares)																0
Issuance of stock to consultants for services													8			$ 8
Stock-based compensation expense related to employee and director stock options													1,316			1,316
Stock-based compensation expense related to non-employee stock options													269			269
Balance (in shares) at Dec. 31, 2016												15,269,000
Balance at Dec. 31, 2016												$ 153	110,619		$ (103,671)	7,101
Issuance of stock and warrants, net of offering costs (in shares)	3,977,000
Issuance of stock and warrants, net offering costs												$ 40	7,389			7,429
Fair market value of warrants transferred to equity upon exercise													2,103			2,103
Warrant modification													$ 270			$ 270
Vesting of restricted stock awards (in shares)						73,000			41,000
Vesting of restricted stock awards						$ 1	$ 173	$ 174		$ 133	$ 133
Shares retired as a result of the 1 for 25 reverse stock split (in shares)												(2,000)