Long-Term Obligations (Details) (USD $)
 1 Months Ended 1 Months Ended 1 Months Ended 0 Months Ended 9 Months Ended
Sep. 30, 2013
Dec. 31, 2012
Jun. 30, 2013
Revolving credit facility
Sep. 30, 2013
Revolving credit facility
Jun. 30, 2013
Revolving credit facility
LIBOR
Jun. 30, 2013
Revolving credit facility
Prime rate
Sep. 30, 2013
Term borrowings
item
Jun. 30, 2013
Term borrowings
Jun. 30, 2013
Term borrowings
Prime rate
Aug. 12, 2013
Unsecured notes payable
Sep. 30, 2013
Unsecured notes payable
item
Long-Term Obligations                      
Maximum borrowing capacity     $ 13,000,000         $ 2,750,000      
Variable interest rate basis         LIBOR prime     prime    
Basis spread on variable rate (as a percent)         2.50%       0.50%    
Interest rate at the end of period (as a percent)       3.25%     3.75%        
Annual commitment fee     20,000                
Commitment fee for quarterly unused capacity (as a percent)     0.375%                
Number of equal monthly payments of principal plus interest             39        
Current borrowing capacity       13,000,000     2,000,000        
Borrowings outstanding       0              
Settlement Obligation                      
Implied interest rate (as a percent)                     3.75%
Number of settlement obligations accelerated and became due and payable                     1
Final payment of obligation                   2,100,000  
Interest expense recorded                   200,000  
Future annual payments on the settlement obligations                      
2013 20,000                    
2014 920,000                    
2015 20,000                    
2016 20,000                    
Total 980,000                    
Less amount representing interest (33,000)                    
Present value of settlement obligations 947,000                    
Less current portion of settlement obligations (887,000) (2,229,000)                  
Long-term portion of settlement obligations $ 60,000