Intangible Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Finite lived intangible assets disclosures
Weighted-Average Life	10 years
Additional disclosures
Net book value of intangible assets	$ 976,000	$ 225,000
Amortization expense	$ 243,000	229,000	$ 229,000
Purchased Patents
Finite lived intangible assets disclosures
Weighted-Average Life	10 years
Gross Carrying Amount	$ 2,292,000	2,292,000
Accumulated Amortization	$ 2,292,000	$ 2,067,000
Patent defense costs
Finite lived intangible assets disclosures
Weighted-Average Life	9 years 6 months
Gross Carrying Amount	$ 994,000
Accumulated Amortization	$ 18,000