Commitments (Details) (USD $)	12 Months Ended						12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Capital Lease Obligations [Member]	Dec. 31, 2012 Capital Lease Obligations [Member]	Dec. 31, 2013 Property [Member]	Dec. 31, 2013 Property [Member] Capital Lease Obligations [Member]	Dec. 31, 1996 Property [Member] Capital Lease Obligations [Member]	Dec. 31, 2013 Equipment [Member]
Property Subject to or Available for Operating Lease [Line Items]
Term of lease							13 years	20 years
Capital leased property	$ 25,170,000	$ 14,148,000						$ 12,300,000
Increase in capital leased property							11,700,000
Capital lease obligations								12,300,000
Increase in capital lease obligations							15,500,000
Net book value of capital asset							13,100,000
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments, Fiscal Year Maturity [Abstract]
2014	1,533,000					1,500,000			33,000
2015	1,568,000					1,538,000			30,000
2016	1,577,000					1,576,000			1,000
2017	1,617,000					1,616,000			1,000
2018	1,656,000					1,656,000			0
Remainder	14,484,000					14,484,000			0
Total minimum obligations	22,435,000					22,370,000			65,000
Less amounts representing interest (ranging from 5.8% to 18.8%)	(6,877,000)					(6,876,000)			(1,000)
Net present value of minimum obligations	15,558,000					15,494,000			64,000
Less current portion	(657,000)	(1,241,000)				(625,000)			(32,000)
Long-term capital lease obligations at December 31, 2013	14,901,000	3,803,000				14,869,000			32,000
Interest rate percentage, minimum (in hundredths)				5.80%
Interest rate percentage, maximum (in hundredths)				18.80%
Annual rent increase percentage				2.50%
Accumulated amortization for property and equipment under capital leases				12,100,000	11,700,000
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2014	645,000
2015	551,000
2016	410,000
2017	295,000
2018	289,000
Remainder	1,531,000
Total minimum lease payments	3,721,000
Rent expense charged to operations	1,100,000	1,100,000	1,200,000
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance Beginning of Year	226,000	953,000	1,079,000
Accruals	70,000	(393,000)	257,000
Warranty Expenses	(183,000)	(334,000)	(383,000)
Balance End of Year	$ 113,000	$ 226,000	$ 953,000