Investments (Details) - USD ($)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Cost $ 7,691,541 $ 7,948,486
Gross Unrealized Losses 89,337 34,693
Fair Value 7,602,204 7,913,793
Cost    
Less than 1 year 4,660,286  
1 to 3 years 3,031,255  
Fair Value    
Less than 1 year 4,592,680  
1 to 3 years 3,009,524  
U.S. corporations    
Cost 6,176,341 6,433,286
Gross Unrealized Losses 68,381 27,067
Fair Value 6,107,960 6,406,219
International corporations    
Cost 1,515,200 1,515,200
Gross Unrealized Losses 20,956 7,626
Fair Value $ 1,494,244 $ 1,507,574