Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	At-the-market offering	At-the-market offering Common Stock	At-the-market offering Additional Paid-in Capital	At-the-market offering Accumulated Other Comprehensive Income (Loss)	Private placement	Private placement Common Stock	Private placement Additional Paid-in Capital	Private placement Accumulated Other Comprehensive Income (Loss)
Balance at Mar. 31, 2014	$ 112,259	$ 79	$ 967,100	$ (370)	$ 1,839	$ (856,389)
Balance (in shares) at Mar. 31, 2014		7,893
Issuance of common stock - ESPP	124	$ 0	124		0
Issuance of common stock - ESPP (in shares)		17
Issuance of common stock - restricted shares	0	$ 3	(3)
Issuance of common stock - restricted shares (in shares)		301
Stock-based compensation expense	5,936		5,936		0
Issuance of stock for 401(k) match	392	$ 0	392		0
Issuance of stock for 401(k) match (in shares)		35
Issuance of common stock							$ 5,839	$ 4	$ 5,835	$ 0	$ 5,225	$ 9	$ 5,216	$ 0
Issuance of common stock (in shares)								375				909
Issuance of common stock to settle liabilities	1,323	$ 1	1,322		0
Issuance of common stock to settle liabilities (in shares)		94
Reverse stock split	(1)		(1)
Repurchase of treasury stock	(401)			(401)	0
Cumulative translation adjustment	(2,147)				(2,147)
Net loss	(48,656)					(48,656)
Balance at Mar. 31, 2015	79,893	$ 96	985,921	(771)	(308)	(905,045)
Balance (in shares) at Mar. 31, 2015		9,624
Issuance of common stock - ESPP	30	$ 0	30		0
Issuance of common stock - ESPP (in shares)		8
Issuance of common stock - restricted shares	0	$ 4	(4)
Issuance of common stock - restricted shares (in shares)		409
Stock-based compensation expense	3,248		3,248		0
Issuance of stock for 401(k) match	377	$ 1	376		0
Issuance of stock for 401(k) match (in shares)		66
Issuance of common stock	22,282	$ 40	22,242		0
Issuance of common stock (in shares)		4,000
Repurchase of treasury stock	(110)			(110)	0
Cumulative translation adjustment	968				968
Net loss	(23,139)					(23,139)
Balance at Mar. 31, 2016	83,549	$ 141	1,011,813	(881)	660	(928,184)
Balance (in shares) at Mar. 31, 2016		14,107
Issuance of common stock - restricted shares	0	$ 2	(2)
Issuance of common stock - restricted shares (in shares)		174
Stock-based compensation expense	2,892		2,892
Issuance of stock for 401(k) match	284	$ 0	284
Issuance of stock for 401(k) match (in shares)		53
Issuance of common stock	2,527	$ 4	2,523
Issuance of common stock (in shares)		380
Repurchase of treasury stock	(490)			(490)
Cumulative translation adjustment	(1,163)				(1,163)
Net loss	(27,373)					(27,373)
Balance at Mar. 31, 2017	$ 60,226	$ 147	$ 1,017,510	$ (1,371)	$ (503)	$ (955,557)
Balance (in shares) at Mar. 31, 2017		14,714