Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Accumulated depreciation, vessels	$ 58,027,166	$ 49,148,080
Accumulated amortization, other fixed assets	$ 183,670	$ 159,827
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	45,091,578	37,666,059
Common stock, shares outstanding (in shares)	45,091,578	37,666,059