Subsequent Events (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014 Vessel Investment [Member] Scenario, Forecast [Member]	Oct. 01, 2013 Subsequent Event [Member] item	Sep. 23, 2013 Subsequent Event [Member] item	Oct. 01, 2013 Subsequent Event [Member] Vessel Investment [Member] item
Subsequent Event [Line Items]
Payment towards acquisition prior to delivery of chemical tankers				$ 2.7
Number of newly-built chemical tankers committed to purchase a minority interest in				2
Amount of investment due upon delivery of vessel	$ 5.8
Number of wholly-owned subsidiaries that entered into a bareboat charter agreement			1
Number of multi-purpose heavy lift dry cargo vessels delivered under agreement entered into by wholly-owned subsidiary		1