Debt (Details) (USD $)	3 Months Ended		6 Months Ended				6 Months Ended		6 Months Ended			0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Apr. 02, 2014	Dec. 31, 2013	Jun. 30, 2014 GE Credit Agreement [Member]	Dec. 31, 2013 GE Credit Agreement [Member]	Jun. 30, 2014 Minimum [Member] GE Credit Agreement [Member]	Jun. 30, 2014 Minimum [Member] LIBOR Rate [Member] GE Credit Agreement [Member]	Jun. 30, 2014 Minimum [Member] Base Rate [Member] GE Credit Agreement [Member]	Apr. 02, 2014 Amended [Member] Maximum [Member] GE Credit Agreement [Member]
Line of Credit Facility [Line Items]
Revolving credit facility, aggregate amount							$ 20,000,000
Revolving credit facility, restriction on cash and cash equivalents	5,973,000		5,973,000			5,350,000	5,000,000	5,000,000	5,000,000
Payment of cash dividends allowed per year, maximum							3,500,000
Revolving credit facility, expiraton date							Oct. 28, 2014
Revolving credit facility, liquidity requirement after effect to stock repurchase									20,000,000
Interest rate on amounts borrowed										4.25%	3.25%
Revolving credit facility, outstanding balance							0	0
Revolving credit facility, aggregate interest rate							6.50%	6.50%
Revolving credit facility, remaining availability							20,000,000	20,000,000
Common stock repurchase, authorized amount												14,000,000
Common stock repurchase, remaining authorized amount	11,500,000		11,500,000		13,500,000
Total interest expense	$ (16,000)	$ 54,000	$ 45,000	$ 104,000