XML 46 R35.htm IDEA: XBRL DOCUMENT v3.20.2
Revenues - Additional Information (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Disaggregation Of Revenue [Line Items]          
Contract assets         $ 0
Contract liabilities $ 20,600,000   $ 20,600,000   $ 36,000,000
Contract liability, revenue recognized $ 10,600,000 $ 10,700,000 $ 31,700,000 $ 25,200,000  
Customer Concentration Risk | Revenues | Maximum | Outside of United States          
Disaggregation Of Revenue [Line Items]          
Revenue 7.00% 1.00% 5.00% 1.00%