Accounts Receivable and Allowance for Expected Credit Losses (Tables)

3 Months Ended

Mar. 31, 2021

Allowance for Doubtful Accounts and Unbilled Services [Abstract]

Schedule of Accounts Receivable

The following table summarizes the components of "Accounts receivable, net" as presented on the Condensed Consolidated Balance Sheets:

	March 31, 2021		December 31, 2020
Accounts receivable:
Billed receivables	$	542,247	$	513,459
Unbilled receivables	294,194		236,285
Allowance for expected credit losses	(37,925)		(38,387)
Accounts receivable, net	$	798,516	$	711,357

Schedule of Accounts Receivable, Writeoff

The following table summarizes the total provision for expected credit losses and write-offs:

	Three Months Ended March 31,
	2021		2020
Provision for expected credit losses (1)	$	4,832	$	3,872
Write-offs	$	6,916	$	6,066

(1)    Adjustments to the allowance for expected credit losses are recorded to selling, general & administrative ("SG&A") expenses on the Condensed Consolidated Statements of Comprehensive Income.