Note 6 - Derivative Instruments and Hedging Activities (Details) - Movement in AOCI Balance - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Movement in AOCI Balance [Abstract]
Opening AOCI balance	$ (1,811,346)		$ (946,676)
Opening AOCI balance	644,113		324,235
Opening AOCI balance	(1,167,233)		(622,441)
Other comprehensive income (loss)before reclassifications	(59,041)		(1,569,387)
Other comprehensive income (loss)before reclassifications	20,995		570,475
Other comprehensive income (loss)before reclassifications	(38,046)	$ 285,136	(998,912)	$ (165,382)
Amount reclassified from accumulated other comprehensive income	577,212		1,222,888
Amount reclassified from accumulated other comprehensive income	(205,257)		(434,859)
Amount reclassified from accumulated other comprehensive income	371,955	$ 145,141	788,029	$ 380,192
Other comprehensive income (loss)	518,171		(346,499)
Other comprehensive income (loss)	(184,262)		135,616
Other comprehensive income (loss)	333,909		(210,883)
Ending AOCI balance	(1,293,175)		(1,293,175)
Ending AOCI balance	459,851		459,851
Ending AOCI balance	$ (833,324)		$ (833,324)