Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2015 M		Mar. 31, 2014		Mar. 31, 2013		Jun. 30, 2013	Jun. 04, 2013
Property, Plant and Equipment [Line Items]
Extended useful life, months			30
Inspection interval			The majority of the company's vessels require certification inspections twice in every five year period
Goodwill					$ 283,699	[1],[2]	$ 297,822	[1]
Goodwill impairment	283,699	56,283	283,699	[2]	56,283
Troms Offshore Supply AS
Property, Plant and Equipment [Line Items]
Goodwill									$ 42,200	$ 42,160	[3]
Maximum
Property, Plant and Equipment [Line Items]
Highly liquid investments, maturities			3 months
Marine Equipment | Maximum
Property, Plant and Equipment [Line Items]
Percentage of salvage values			10.00%
Marine Equipment | Maximum | From Date of Construction
Property, Plant and Equipment [Line Items]
Estimated useful lives, years			25 years
Marine Equipment | Minimum
Property, Plant and Equipment [Line Items]
Percentage of salvage values			5.00%
Marine Equipment | Minimum | From Date of Construction
Property, Plant and Equipment [Line Items]
Estimated useful lives, years			15 years
Marine Equipment | Minimum | Regardless of Date Constructed
Property, Plant and Equipment [Line Items]
Estimated useful lives, years			6 years
Other Property Plant and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives, years			30 years
Other Property Plant and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives, years			3 years
Stacked Vessels
Property, Plant and Equipment [Line Items]
Property plant and equipment average age			20.7		32.2

[1] The total carrying amount of goodwill at December 31, 2013 is net of accumulated impairment charges $30.9 million and $56.3 million related to the Middle East/North Africa and Asia/Pacific segments, respectively.

[2] The total carrying amount of goodwill at December 31, 2014 is net of accumulated impairment charges of $370.9 million.

[3] Subsequently written off in December 2014.