Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity Rollforward (Details)

v3.8.0.1
Shareholders' Equity Rollforward (Details) - USD ($)
$ in Thousands
 9 Months Ended
Sep. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
As of beginning balance $ 185,548
Net income (loss) 43,463
All Other Changes 2,751
As of ending balance 231,762
Share-based compensation 2,700
Proceeds Attributable to Rights Offering 100
Common stock  
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
As of beginning balance 150
As of ending balance 150
Paid-in capital  
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
As of beginning balance 190,621
All Other Changes [1] 2,751
As of ending balance 193,372
Retained earnings (accumulated deficit)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
As of beginning balance (5,296)
Net income (loss) 43,463
As of ending balance 38,167
Accumulated other comprehensive income  
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
As of beginning balance 73
As of ending balance $ 73
Time Vested Restricted Stock Units [Domain]  
Increase (Decrease) in Stockholders' Equity [Roll Forward]  
Shares, Issued 12,252
[1] Includes equity-classified share-based compensation of $2.7 million and $0.1 million from the receipt in May 2017 of proceeds attributable to the rights offering in 2016 that had been held in escrow, net of costs to register our common stock