XML 149 R51.htm IDEA: XBRL DOCUMENT v2.4.0.8
Acquisition - Additional Information (Detail) (USD $)
 1 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Mar. 31, 2012
Jun. 04, 2013
Troms Offshore Supply AS
Mar. 31, 2014
Troms Offshore Supply AS
Business Acquisition [Line Items]          
Business acquisition, description of acquired entity       Troms Offshore owned four deepwater PSVs, and had two additional deepwater PSVs under construction, one of which was delivered shortly after the acquisition and the other delivered in January 2014.  
Business acquisition, cash paid       $ 150,000,000  
Business acquisition, debt assumed       261,300,000  
Business acquisition, Goodwill $ 283,699,000 $ 297,822,000 [1] $ 297,822,000 [1] $ 42,160,000 $ 42,200,000
[1] The total carrying amount of goodwill at March 31, 2012 is net of accumulated impairment charges $30.9 million related to the Middle East/North Africa segment.