Anti-dilutive Security not Included In Diluted per Share Calculations (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	293,796	403,572
Options To Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	140,990	146,726
Common Stock Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	12,063	12,063
Redeemable Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	140,743	244,783