XML 64 R48.htm IDEA: XBRL DOCUMENT v3.10.0.1
DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - A/R, Allowances of A/R and PPE - (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2018
USD ($)
item
Dec. 31, 2017
USD ($)
item
Accounts Receivable    
Number of days for evaluating significant balances for credit risk 30 days  
Number of largest customers | item 5 5
Allowance for Doubtful Accounts    
Bad debt (recoveries) expense $ (34)  
Bad debt (recoveries) expense   $ 80
LONG-LIVED ASSETS    
Depreciation & amortization expense 7,299 7,235
Interest cost capitalized $ 0 $ 0
Consolidated revenues | Customer concentration    
Accounts Receivable    
Concentration risk (as a percent) 78.00% 85.00%
Outstanding A/R balances | Customer concentration    
Accounts Receivable    
Concentration risk (as a percent) 54.00% 57.00%