Notes Payable and Debt Financing (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Apr. 19, 2013
Senior Credit Agreement        
Amount borrowed under the credit facility   $ 1,300 $ 400  
Borrowings on line of credit   $ 3,500 400  
Senior Credit Facility        
Senior Credit Agreement        
Line of credit capacity       $ 24,000
Amount borrowed under the credit facility     $ 14,000  
Borrowings on line of credit $ 1,000