Preferred Stock (Details) (USD $)	12 Months Ended		0 Months Ended	12 Months Ended	0 Months Ended			12 Months Ended		0 Months Ended				12 Months Ended		0 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Mar. 25, 2004 5% preferred stock item	Dec. 31, 2012 5% preferred stock	Mar. 25, 2004 5% preferred stock CEO	Mar. 25, 2004 5% preferred stock Director	Mar. 28, 2005 Series 2 5% preferred stock	Dec. 31, 2012 Series 2 5% preferred stock	Mar. 28, 2005 Series 2 5% preferred stock Minimum	Mar. 28, 2005 Series 2 5% preferred stock CEO	Mar. 28, 2005 Series 2 5% preferred stock Director	Mar. 28, 2005 Series 2 5% preferred stock CFO	Dec. 02, 2005 Series 3 5% preferred stock	Dec. 31, 2012 Series 3 5% preferred stock	Dec. 02, 2005 Series 3 5% preferred stock Minimum	Dec. 02, 2005 Series 3 5% preferred stock CEO	Dec. 02, 2005 Series 3 5% preferred stock Director	Dec. 02, 2005 Series 3 5% preferred stock CFO
Preferred Stock
Dividend rate (as a percent)			5.00%				5.00%						5.00%
Value of shares issued under private placement			$ 5,000,000				$ 2,700,000						$ 1,200,000
Shares issued under private placement			1,000,000		140,000	60,000	1,065,200			260,000	60,000	100,000	564,607			123,853	27,523	68,808
Share issued price (in dollars per share)			$ 5.00				$ 2.50						$ 2.18
Issuance costs incurred for shares issued			275,000				173,000						100,000
Shares of common stock issued upon conversion of preferred stock			1,590,331				1,065,200						564,607
Conversion price per share (in dollars per share)			$ 3.144				$ 2.50						$ 2.18
Number of votes per share that holders of preferred stock will receive			1.5903
Liquidation preference value preferred stock price per share			$ 5.00				$ 2.50						$ 2.18
Redemption price per share (in dollars per share)			$ 5.00						$ 3.25						$ 2.834
Shares outstanding				220,000				460,000						354,056
Dividends Payable
Preferred stock dividends accrued during the period	152,000	151,000		55,000				57,000						39,000
Accrued and unpaid dividends	$ 279,000	$ 123,000