XML 39 R28.htm IDEA: XBRL DOCUMENT v3.10.0.1
Revenue Recognition (Narrative) (Details) - USD ($)
3 Months Ended 9 Months Ended 12 Months Ended
Jan. 01, 2018
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Revenue from Contract with Customer [Line Items]            
Standard product warranty period       1 year    
Unbilled revenue, billed and collected, term       1 year    
Revenues from contract with customer   $ 6,867,000 $ 4,280,000 $ 20,800,000 $ 15,609,000  
Accounts receivable, net   4,381,000   4,381,000   $ 4,528,000
Revenue recognized related to contract liabilities   0   0   $ 721,000
Remaining performance obligation   $ 1,200,000   $ 1,200,000    
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]            
Revenue from Contract with Customer [Line Items]            
Revenues from contract with customer $ 0          
Minimum [Member]            
Revenue from Contract with Customer [Line Items]            
Accounts receivable, balance due       30 days    
Maximum [Member]            
Revenue from Contract with Customer [Line Items]            
Accounts receivable, balance due       60 days