Fair Value Disclosures - Schedule of Assets and Liabilities Carried at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Apr. 04, 2012
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	$ 17,675			$ 18,649
Warrants	2,601			3,633
Derivative liability		200	5,444	529	1,000	2,800	4,500	3,800
Quoted Prices in Active Markets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	17,675			18,649
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrants	2,601			3,633
Derivative liability				$ 529