Debt - Additional Information (Detail) (USD $)	3 Months Ended						0 Months Ended	3 Months Ended		0 Months Ended		3 Months Ended	0 Months Ended				3 Months Ended	0 Months Ended	3 Months Ended		0 Months Ended			3 Months Ended			12 Months Ended	0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Mar. 31, 2013	Mar. 02, 2014 Capital Ventures International	Mar. 31, 2014 Capital Ventures International	Jun. 30, 2014 Senior Convertible Debt	Oct. 09, 2013 Senior Convertible Debt Capital Ventures International	Apr. 04, 2012 Senior Convertible Debt Capital Ventures International	Jun. 30, 2014 Senior Convertible Debt Capital Ventures International	Mar. 02, 2014 New Unsecured Senior Convertible Note	Dec. 31, 2013 New Unsecured Senior Convertible Note	Dec. 31, 2012 New Unsecured Senior Convertible Note	Apr. 04, 2012 New Unsecured Senior Convertible Note	Jun. 30, 2014 New Unsecured Senior Convertible Note Capital Ventures International	Nov. 15, 2013 Senior Secured Loan	Jun. 30, 2014 Senior Secured Loan	Jun. 05, 2012 Senior Secured Loan	Nov. 15, 2013 Senior Secured Loan Hercules Technology Growth Capital	Jun. 05, 2012 Senior Secured Loan Hercules Technology Growth Capital	Jun. 05, 2012 Senior Secured Loan Hercules Technology Growth Capital	Jun. 30, 2014 Senior Secured Loan Hercules Technology Growth Capital	Dec. 31, 2013 Senior Secured Loan Hercules Technology Growth Capital	Jun. 30, 2013 Senior Secured Loan Hercules Technology Growth Capital	Mar. 31, 2013 Senior Secured Loan Hercules Technology Growth Capital	Jun. 05, 2012 Senior Secured Loan Hercules Technology Growth Capital Minimum
Debt Instrument [Line Items]
Net proceeds after fees and expenses of purchase agreement											$ 23,200,000
Conversion price											$ 4.85			$ 3.10	$ 3.19	$ 4.85
Premium over closing price, percentage											20.00%
Period before first installment payment											4 months
Shares registered for resale											10,262,311
Derivative liability of note	2,636,000		2,601,000								3,800,000						500,000
Number of shares received from warrants received to purchase common stock											3,094,060							256,410			256,410	139,276	139,276
Strike price per share										$ 2.61	$ 5.45	$ 2.57						$ 1.95	$ 1.94		$ 1.95	$ 3.59	$ 3.59	$ 1.94	$ 1.95
Fair value of warrants at issuance											7,000,000												400,000
Increase in derivative liability																	1,500,000
Total debt discount being amortized into interest expense																	13,100,000							100,000
Non-cash interest expense amortization of debt discount	200,000	1,700,000							1,500,000															100,000		100,000
Percentage of stock discount	85.00%
Number of trading days for valuation of shares	10 days
Non-cash interest expense issuing stock at discount		100,000
Debt conversion, shares issued							6,600,000						6,600,000
Loss on extinguishment of debt								(5,200,000)
Legal and origination costs																									200,000		300,000
Debt, face amount																				10,000,000	10,000,000	10,000,000	10,000,000
Proceeds from the issuance of debt, net of expenses																					9,800,000		9,700,000
Interest rate on loan																						11.00%	11.00%
Prime rate																												3.75%
End of term fee																								500,000			500,000
Interest expense	500,000	2,100,000																						1,000,000			1,200,000
Minimum amount of proceeds from specified asset dispositions for mandatory prepayment feature																								1,000,000
Covenant, unrestricted cash balance requirement																					15,000,000			12,500,000
Net proceeds from sale of common stock																								5,000,000
Repayments of term loan																								2,500,000
Combined principal balances of the term loans		$ 14,389,000		$ 10,411,000	$ 10,411,000	$ 15,380,000																		$ 7,500,000