Significant Accounting Policies (Estimated Annual Patent Amortization Expense) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Total patent amortization expense	$ 307,000	$ 338,000
Patents [Member]
2017	31,000
2018	31,000
2019	31,000
2020	31,000
2021	31,000
Thereafter	152,000
Total patent amortization expense	$ 307,000