XML 191 R148.htm IDEA: XBRL DOCUMENT v3.20.1
Operating Segment and Related Information - Concentration Risk (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Customer A | Sales Revenue, Net | Customer Concentration Risk | Telecommunications    
Segment Reporting Information [Line Items]    
Percentage of total 10.30% 11.00%