Description of Business and Summary of Significant Accounting Policies - Schedule of Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 329,938	$ 396,518
Less: allowance for credit losses	(33,368)	(26,828)
Accounts receivable, net of allowance	296,570	369,690
Accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	128,145	129,953
Unbilled accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 201,793	$ 266,565