Quarterly report pursuant to Section 13 or 15(d)

Underwritten Offering Common Stock and At-the-Market Offering Program (Details)

Underwritten Offering Common Stock and At-the-Market Offering Program (Details) $ / shares in Units, $ in Thousands					5 Months Ended	6 Months Ended		12 Months Ended
	Oct. 21, 2016 USD ($)	Apr. 22, 2016 USD ($) shares	Apr. 19, 2016 $ / shares shares	Aug. 28, 2015 USD ($)	Sep. 30, 2016 shares	Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($)	Mar. 31, 2016 USD ($) shares
Number of common stock shares available in public offering			2,700,000
Beneficial ownership of common stock resulting from purchase of stock in public offering (as a percent)			4.99
Number of warrants or shares of common stock to be sold to purchase common stock			2
Net proceeds from offering of common stock and warrants \| $	$ 6,800	$ 13,100				$ 13,113	$ 1,244
Common stock sold (in shares)								6,900,000
Net proceeds from sale of the common stock, after deducting fees and other offering expenses (in dollars) \| $								$ 12,700
Maximum
Aggregate offering price for at-the-market offering program \| $				$ 30,000
Series A Warrants
Number of shares of common stock that could be purchased with warrants			4,100,000
Number of warrants or shares of common stock to be sold to purchase common stock			1
Number of shares of common stock purchased with each warrant			1
Exercise price (in dollars per share) \| $ / shares			$ 3.50
Length of time from issue date until warrants are exercisable			6 months
Length of time from exercise date until warrants expire			5 years
Balance, April 22, 2016 (in shares)					4,107,500
Balance, end of period (in shares)		4,107,500			4,107,500	4,107,500
Series B Warrants
Number of warrants or shares of common stock to be sold to purchase common stock			2
Exercise price (in dollars per share) \| $ / shares			$ 3.48
Length of time from exercise date until warrants expire			9 months
Balance, April 22, 2016 (in shares)					5,515,000
Warrants exercised (in shares)					(4,107,500)
Balance, end of period (in shares)		5,515,000			1,407,500	1,407,500
Series B Warrants \| Maximum
Number of shares of common stock that could be purchased with warrants			5,500,000