Note 2 - Vessel Acquisitions and Dispositions (Details) - Vessels Held for Sale (Spv [Member], Clwyd Supporter [Member], North Sea [Member])	6 Months Ended
	Jun. 30, 2013 hp T ft
Spv [Member] | Clwyd Supporter [Member] | North Sea [Member]
Note 2 - Vessel Acquisitions and Dispositions (Details) - Vessels Held for Sale [Line Items]
Clwyd Supporter	1984
Clwyd Supporter (in Feet)	266
Clwyd Supporter (in Horsepower)	10,700	[1]
Clwyd Supporter (in US Ton)	1,350	[2]
Clwyd Supporter	Jan-13

[1] BHP - Brake Horsepower

[2] DWT - Deadweight Tons