Accounts and Other Receivables - Company's Accounts Receivable and Securitized Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross receivables	$ 2,324,577	$ 2,610,824
Less allowance for credit losses	(83,882)	(70,890)	$ (64,665)	$ (59,963)
Net accounts and other receivables and securitized accounts receivable	2,240,695	2,539,934
Gross domestic accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross receivables	847,080	734,410
Gross domestic securitized accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross receivables	688,000	970,973
Gross foreign receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross receivables	$ 789,497	$ 905,441