Interim Financial Statements (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Unbilled receivables	$ 150,300		$ 125,400
Contract with Customer, Liability	50,100		17,500
Deferred revenue and customer advances	26,958		$ 16,177
Contract with Customer, Liability, Revenue Recognized	$ 12,500	$ 14,500