Warranty Reserve (Details) (USD $)	0 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Warranty Reserve.
Beginning balance - January 1	$ 1,608,131	$ 2,671,409
Addition for Relion acquisition			233,528
Additions for current year deliveries			960,894	970,775
Reductions for payments made			1,491,111	2,034,053
Ending balance - December 31			$ 1,311,442	$ 1,608,131