XML 49 R37.htm IDEA: XBRL DOCUMENT v3.8.0.1
Earnings per share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Earnings Per Share [Abstract]        
Net income $ 20,988 $ 51,845 $ 72,685 $ 127,564
Basic weighted-average shares outstanding 71,699 71,588 71,693 71,588
Effect of dilutive share-based compensation awards 68   70  
Diluted weighted-average shares outstanding 71,767 71,588 71,763 71,588
Earnings per share, basic $ 0.29 $ 0.72 $ 1.01 $ 1.78
Earnings per share, diluted $ 0.29 $ 0.72 $ 1.01 $ 1.78