Shareholders' Equity (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of stock option activity under the plans
Number of Shares, Beginning Balance	1,939,475	1,942,723
Weighted Average Exercise Price, Beginning Balance	$ 4.49	$ 3.66
Weighted Average Remaining Contractual Life (in years), Beginning Balance	4 years 2 months 27 days	4 years 3 months 29 days	4 years 10 months 28 days
Granted at fair value, Number of Shares	244,125	423,715
Granted at fair value, Weighted Average Exercise Price	$ 3.27	$ 7.93
Exercised, Number of Shares	(90,786)	(208,821)
Exercised, Weighted Average Exercise Price	$ 2.41	$ 2.94
Forfeited, Number of Shares	(327,422)	(44,334)
Forfeited, Weighted Average Exercise Price	$ 6.67	$ 3.32
Expired, Number of Shares	(225,774)	(173,808)
Expired, Weighted Average Exercise Price	$ 7.24	$ 5.74
Number of Shares, Ending Balance	1,539,618	1,939,475	1,942,723
Weighted Average Exercise Price, Ending Balance	$ 3.55	$ 4.49	$ 3.66
Weighted Average Remaining Contractual Life (in years), Ending Balance	4 years 2 months 27 days	4 years 3 months 29 days	4 years 10 months 28 days
Aggregate Intrinsic Value, Ending Balance	$ 363,000
Vested and expected to vest, Number of Shares, Ending Balance	1,491,531
Vested and expected to vest, Weighted Average Exercise Price, Ending Balance	$ 3.55
Vested and expected to vest, Weighted Average Remaining Contractual Life (in years), Ending Balance	4 years 1 month 17 days
Vested and expected to vest, Aggregate Intrinsic Value, Ending Balance	362,000
Exercisable, Number of Shares, Ending Balance	1,181,590
Exercisable, Weighted Average Exercise Price, Ending Balance	$ 3.49
Exercisable, Weighted Average Remaining Contractual Life (in years), Ending Balance	3 years 1 month 21 days
Exercisable, Aggregate Intrinsic Value, Ending Balance	$ 343,000