Warrants (Schedule of Warrant Activity) (Detail) - shares shares in Thousands	3 Months Ended	6 Months Ended
	Sep. 30, 2014	Jun. 30, 2015
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		8,540
Granted		14,006
Class of Warrant or Right, Expired		238
Warrants outstanding , Ending balance		22,308
March 2015 Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		0
Granted		14,006
Warrants outstanding , Ending balance		14,006
Expiration		Mar. 18, 2020
September 2013 Warrant [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		3,973
Granted		0
Warrants outstanding , Ending balance		3,973
Expiration		Sep. 18, 2018
December 2012 Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		3,031
Granted		0
Warrants outstanding , Ending balance		3,031
Expiration		Dec. 31, 2017
April 2011 Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		615
Granted		0
Warrants outstanding , Ending balance		615
Expiration		Apr. 30, 2017
March 2011 Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		176
Granted		0
Warrants outstanding , Ending balance		176
Expiration		Mar. 31, 2016
March 2010 Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		25
Granted		0
Warrants outstanding , Ending balance		25
Expiration		Mar. 31, 2016
Consultant Warrants [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance		720
Granted		0
Class of Warrant or Right, Expired		238
Warrants outstanding , Ending balance		482
Consultant Warrants [Member] | Minimum [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Expiration	Dec. 31, 2014
Consultant Warrants [Member] | Maximum [Member]
Class of Warrant or Right, Outstanding [Roll Forward]
Expiration	Dec. 31, 2020