Annual report pursuant to Section 13 and 15(d)

Notes Payable (NFS Forgivable Loans) (Details)

v3.19.1
Notes Payable (NFS Forgivable Loans) (Details)
12 Months Ended
Nov. 04, 2011
USD ($)
installment
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Revolving Credit Facility        
Debt Instrument [Line Items]        
Amount outstanding     $ 0  
NFS Forgivable Loans        
Debt Instrument [Line Items]        
Debt instrument, term 7 years      
Loans payable $ 15,000,000      
Number of installments | installment 7      
Annual installment $ 2,143,000      
Forgiveness, principal   $ 2,143,000 2,143,000 $ 2,143,000
Forgiveness, interest   $ 79,000 $ 295,000 $ 408,000
NFS Forgivable Loans | Minimum        
Debt Instrument [Line Items]        
Effective percentage 6.00%      
NFS Forgivable Loans | Maximum        
Debt Instrument [Line Items]        
Effective percentage 11.00%