Organization and Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of changes in estimated product warranty liabilities
Balance, beginning of period	$ 427,459	$ 646,113	$ 369,311
Utilization of accrual	(470,301)	(528,433)	(566,466)
Warranty expense	526,563	309,779	843,268
Balance, end of period	$ 483,721	$ 427,459	$ 646,113