Net (Loss) Income Per Common Share - Schedule of Potential Dilutive Common Shares (Detail)	12 Months Ended
	Dec. 31, 2016 shares
Minimum [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	342,171,887
Minimum [Member] | Series A Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	10,065,629
Minimum [Member] | Series B Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	266,666,667
Minimum [Member] | Restricted Shares Subject to Vesting [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	4,039,591
Minimum [Member] | Warrants Outstanding [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	61,400,000
Maximum [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	419,378,237
Maximum [Member] | Series A Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	10,065,629
Maximum [Member] | Series B Conversion Per Share Below 2.25 [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	1,015,874
Maximum [Member] | Series B Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	342,857,143
Maximum [Member] | Restricted Shares Subject to Vesting [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	4,039,591
Maximum [Member] | Warrants Outstanding [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive shares if converted to common	61,400,000