Conversion of Redeemable Convertible Preferred Stock - Additional Information (Detail) (USD $)	12 Months Ended		1 Months Ended	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Mar. 31, 2013	Mar. 31, 2013
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Remaining value of the Series B and Series A subsequent to extinguishment	$ 1,085,000
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Fair Value Measurements, Valuation Techniques		At the time of the March 2013 financing, the valuations were weighted as follows IPO, 40%; sale of the Company/assets, 45%; dissolution, 10%; and remain private, 5%. The estimated fair value of one share of common and preferred stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability weighted value per share.
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | IPO [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Percentage of weight used to determine fair value			40.00%
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | Sale of Company Assets [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Percentage of weight used to determine fair value			45.00%
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | Dissolution [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Percentage of weight used to determine fair value			10.00%
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | Private Placement [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Percentage of weight used to determine fair value			5.00%
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | Minimum [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Fair value of equity			20,000,000	20,000,000
PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member] | Maximum [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Fair value of equity			215,000,000	215,000,000
Series B Convertible Preferred Stock 0.00001 Par Value [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Decreases in the redemption value of the Company's Series B and Series A shares				30,000,000
Series B Convertible Preferred Stock 0.00001 Par Value [Member] | PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Price per share			0.20	$ 0.20
Series A Convertible Preferred Stock 0.00001 Par Value [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Decreases in the redemption value of the Company's Series B and Series A shares				56,100,000
Series A Convertible Preferred Stock 0.00001 Par Value [Member] | PWERM Method [Member] | Redeemable Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Price per share			0.15	$ 0.15
Series A and Series B Redeemable Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Convertible preferred stock, liquidation preference value			4,000,000	4,000,000
Series A and B Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Gain on extinguishment of Series B and Series A			86,200,000
Remaining value of the Series B and Series A subsequent to extinguishment			1,100,000
Series A, Series B and Series C Redeemable Convertible Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Outstanding shares conversion of convertible securities		115,982