Restated Consolidated Balance Sheets (Parenthetical) (Detail) (USD $)	Mar. 31, 2014		Dec. 31, 2013		Sep. 15, 2013	Mar. 31, 2013	Nov. 08, 2013
Common stock, par value	$ 0.01	[1]	$ 0.01	[1]	$ 0.01	$ 0.01
Common stock, shares authorized	1,500,000,000	[1]	750,000,000	[1]		240,000,000
Common stock, issued	769,931,938	[1]	239,234,725	[1]		154,322,183
Common stock, outstanding	769,931,938	[1]	239,234,725	[1]		154,322,183
Series A Convertible Preferred Stock [Member]
Convertible preferred stock, par value						$ 0.01
Convertible preferred stock, shares authorized						545,454
Convertible preferred stock, issued						545,454
Convertible preferred stock, outstanding						545,454
Convertible preferred stocK, liquidation preference						$ 11.00
Series B Convertible Preferred Stock [Member]
Convertible preferred stock, par value						$ 0.01
Convertible preferred stock, shares authorized						283,018
Convertible preferred stock, issued						283,018
Convertible preferred stock, outstanding						283,018
Convertible preferred stocK, liquidation preference						$ 10.60
Convertible Preferred Stock [Member]
Convertible preferred stock, par value	$ 0.01	[1]	$ 0.01	[1]		$ 0.01
Convertible preferred stock, shares authorized	100,000,000	[1]	100,000,000	[1]		100,000,000
Convertible preferred stock, issued	42,654,919	[1]	42,199,547	[1]		35,863,711
Convertible preferred stock, outstanding	42,654,919	[1]	42,199,547	[1]		35,863,711
Series D preferred stock [Member]
Convertible preferred stock, par value	$ 0.01	[1]	$ 0.01	[1]	$ 0.01
Convertible preferred stock, shares authorized	21,735,008	[1]	21,735,008	[1]
Convertible preferred stock, issued	21,735,008	[1]	21,735,008	[1]
Convertible preferred stock, outstanding	21,735,008	[1]	21,735,008	[1]
Convertible preferred stocK, liquidation preference							$ 13.59

[1] For discussion on the restatement adjustments, see Note 2 - Restatement of Previously Issued Financial Statements.