Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Detail)

v3.8.0.1
Stockholders' Equity - Additional Information (Detail)
 9 Months Ended
Sep. 30, 2017
USD ($)
shares
Sep. 30, 2016
USD ($)
Jun. 30, 2017
shares
Mar. 31, 2017
shares
Jan. 31, 2017
USD ($)
shares
Dec. 31, 2016
USD ($)
shares
Class of Stock [Line Items]            
Proceeds from the issuance of common stock | $ $ 218,195,000 $ 58,886,000        
Shares issued value | $ $ 217,088,000 $ 57,374,000        
Common stock, shares issued | shares 214,000,000         109,600,000
Shares issued value | $ $ 1,943,000         $ 101,000
Conversion ratio 1          
At-the-Market Program            
Class of Stock [Line Items]            
Number of shares issued | shares 1,000,000.0          
Shares issued value | $ $ 10,300,000          
Fees and commissions | $ 500,000          
Maximum | At-the-Market Program            
Class of Stock [Line Items]            
Proceeds from the issuance of common stock | $ $ 200,000,000          
TOTAL Delaware Inc            
Class of Stock [Line Items]            
Common stock, shares issued | shares         35,400,000  
Shares issued value | $         $ 207,000,000  
Shares exchanged for issue of common stock | shares         46,000,000  
GE Oil & Gas, Inc.            
Class of Stock [Line Items]            
Number of shares converted | shares     5,500,000      
GE Oil & Gas, Inc. | Series A Preferred Stock            
Class of Stock [Line Items]            
Number of shares converted | shares       5,500,000    
GE Oil & Gas, Inc. | Series B Preferred Stock            
Class of Stock [Line Items]            
Number of shares converted | shares     5,500,000