XML 33 R23.htm IDEA: XBRL DOCUMENT v3.8.0.1
Summary of Significant Accounting Policies - Revenue Recognition - Accounts receivable, net (Details) - USD ($)
Mar. 31, 2018
Dec. 31, 2017
Accounts receivable, net    
Trade accounts receivable $ 9,440,000 $ 3,576,000
Allowance for accounts receivable 572,000 147,000
Unbilled accounts receivable 36,000  
Accounts receivable, net 8,904,000 3,429,000
Non-distributor    
Accounts receivable, net    
Allowance for accounts receivable 173,000 147,000
Distributor    
Accounts receivable, net    
Allowance for accounts receivable $ 399,000 $ 0