Derivative Instruments and Fair Value Measurements (Details 3) (USD $)	Jun. 30, 2012	Dec. 31, 2011
Fair Value, Inputs, Level 1 [Member]
Assets:
Bunker swaps	$ 0	$ 142,750
Bunker derivative instruments	0	0
Liabilities:
Interest rate swaps	0	0
Bunker swaps	0	53,000
Bunker derivative instruments	0	0
Fair Value, Inputs, Level 2 [Member]
Assets:
Bunker swaps	0	0
Bunker derivative instruments	0	261,000
Liabilities:
Interest rate swaps	6,223,622	9,486,116
Bunker swaps	0	0
Bunker derivative instruments	0	104,640
Fair Value, Inputs, Level 3 [Member]
Assets:
Bunker swaps	0	0
Bunker derivative instruments	0	0
Liabilities:
Interest rate swaps	0	0
Bunker swaps	0	0
Bunker derivative instruments	$ 0	$ 0