Note 2 - Vessel Acquisitions and Dispositions (Details) - Vessels Disposed of Since December 31, 2012	9 Months Ended
	Sep. 30, 2013 T ft hp
Significant Acquisitions and Disposals [Line Items]
Length (feet) (in Feet)	271
BHP (in Horsepower)	9,990
DWT (in US Ton)	3,600
Spv [Member] | Clwyd Supporter [Member] | North Sea [Member]
Significant Acquisitions and Disposals [Line Items]
Year Built	1984
Length (feet) (in Feet)	266
BHP (in Horsepower)	10,700	[1]
DWT (in US Ton)	1,350	[2]
Month Disposed	Jan-13
LgSPV [Member] | Highland Champion [Member] | North Sea [Member]
Significant Acquisitions and Disposals [Line Items]
Year Built	1979
Length (feet) (in Feet)	265
BHP (in Horsepower)	4,800
DWT (in US Ton)	3,910
Month Disposed	Aug-13
LgSPV [Member] | Highland Pride [Member] | North Sea [Member]
Significant Acquisitions and Disposals [Line Items]
Year Built	1992
Length (feet) (in Feet)	265
BHP (in Horsepower)	6,600
DWT (in US Ton)	3,080
Month Disposed	Aug-13
LgSPV [Member] | Highland Warrior [Member] | Americas [Member]
Significant Acquisitions and Disposals [Line Items]
Year Built	1981
Length (feet) (in Feet)	265
BHP (in Horsepower)	5,300
DWT (in US Ton)	2,450
Month Disposed	Sep-13

[1] BHP - Brake Horsepower

[2] DWT - Deadweight Tons