Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($)
Dec. 31, 2015
Dec. 31, 2014
Jun. 12, 2014
Compensating Balances [Line Items]      
Restricted cash, short-term $ 1,861,000 $ 0  
Amended New Loan and Security Agreement      
Compensating Balances [Line Items]      
Restricted cash, short-term 1,900,000    
Available borrowing capacity 3,100,000    
Amended New Loan and Security Agreement | Minimum      
Compensating Balances [Line Items]      
Minimum amount required to be maintained by the company at all times $ 5,000,000   $ 5,000,000