Summary of Significant Accounting Policies - Advertising and Warranty Costs (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Advertising Expense and Warranty Accrual [Abstract]
Advertising expense	$ 57,000	$ 30,000	$ 63,000
Warranty costs on the balance sheet		$ 100,000