CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Revenues, net of commissions	$ 313,432,431	$ 265,036,066	$ 192,574,826
Voyage expenses	44,345,774	3,726,847	0
Vessel expenses	85,049,671	72,983,630	50,161,091
Charter hire expenses	41,215,875	9,982,677	0
Depreciation and amortization	73,084,105	62,945,478	44,329,258
General and administrative expenses	37,559,639	40,029,261	32,713,917
Loss (gain) on sale of vessel	509,076	(291,011)	0
Total operating expenses	281,764,140	189,376,882	127,204,266
Operating Income	31,668,291	75,659,184	65,370,560
Interest expense	46,769,965	48,885,674	28,904,610
Interest income	(130,007)	(369,558)	(204,610)
Write-off of deferred financing costs	0	0	3,383,289
Other expenses (income)	(151,918)	298,418	0
Total other expense, net	46,488,040	48,814,534	32,083,289
Net income (loss)	$ (14,819,749)	$ 26,844,650	$ 33,287,271
Weighted average shares outstanding:
Basic (in shares)	62,621,771	62,204,443	55,897,946
Diluted (in shares)	62,621,771	62,417,247	55,923,308
Per share amounts:
Basic net income (loss) (in dollars per share)	$ (0.24)	$ 0.43	$ 0.60
Diluted net income (loss) (in dollars per share)	$ (0.24)	$ 0.43	$ 0.60