Dispositions and Discontinued Operations - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013 Inland	Mar. 31, 2013 Domestic Liftboats	Dec. 31, 2013 Various Inland barge
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Barges Sold			12
Interest expense allocated to discontinued operations	$ 0.8	$ 0.6