Annual report pursuant to Section 13 and 15(d)

Significant Accounting Policies - Summary of Potentially Dilutive Adjustments to Weighted Average Number of Common Shares Excluded from Calculation (Detail)

v3.6.0.2
Significant Accounting Policies - Summary of Potentially Dilutive Adjustments to Weighted Average Number of Common Shares Excluded from Calculation (Detail) - shares
shares in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation of earnings per share (shares) 9,311 6,454
Common stock purchase warrants    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation of earnings per share (shares) 7,033 4,372
Stock options    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation of earnings per share (shares) 2,198 1,961
Restricted shares of common stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation of earnings per share (shares) 80 121