v3.5.0.2
Acquisition of Ship-to-Ship Transfer Business - Summarized Consolidated Pro Forma Financial Information (Detail) - Ship to Ship Transfer Business [Member]
$ / shares in Units, $ in Thousands
9 Months Ended
Sep. 30, 2015
USD ($)
$ / shares
Business Acquisition [Line Items]  
Revenues | $ $ 385,465
Net Income | $ $ 125,274
Earnings per common share:  
Basic (usd per share) | $ / shares $ 0.97
Diluted (usd per share) | $ / shares $ 0.97