Revenues and Customer Receivables - Activity of Allowance for Credit Losses (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($)
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of December 31, 2019	$ 2,208
Provision for expected credit losses, net of writeoffs and recoveries	2,547
Initial allowance for expected credit losses on purchased customer receivables	0
Balance as of September 30, 2020	$ 4,755