XML 73 R58.htm IDEA: XBRL DOCUMENT v3.3.1.900
Stock-Based Compensation Plans Market Stock Units (Details) - USD ($)
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
MSU Expense $ 500,000 $ 300,000 $ 200,000
Number of Market Stock Units      
Outstanding on December 31, 2014 88,600    
Granted 30,633    
Exchanged for shares (24,493)    
Cancelled (6,970)    
Outstanding on December 31, 2015 87,770 88,600  
Maximum Shares Potentially Issuable      
Outstanding on December 31, 2014 132,900    
Granted 45,949    
Exchanged for shares (36,739)    
Cancelled (10,455)    
Outstanding on December 31, 2015 131,655 132,900  
Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Potential Shares From MSU Vest $ 0    
Trading days 30 days    
Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Potential Shares From MSU Vest $ 1.50    
Trading days 60 days