Accounts Receivable, Net (Tables)

12 Months Ended

Dec. 31, 2021

Receivables [Abstract]

Summary of Accounts Receivable

Accounts receivable are as follows (in millions):

	December 31,
	2021			2020
Accounts receivable	$	521.9		$	478.9
Unbilled accounts receivable		209.4			185.9
Allowance for credit losses		(17.9	)		(16.8	)
Total accounts receivable, net	$	713.4		$	648.0

Schedule of Allowance for Credit Losses

The following table represents the activity for the allowance for credit losses (in millions):

	Year Ended December 31,
	2021			2020			2019
Balance at beginning of period	$	16.8		$	13.2		$	9.4
Charge to costs and expenses		8.2			7.7			6.2
Write-offs, net of recoveries		(7.0	)		(4.2	)		(2.4	)
Foreign currency impact		(0.1	)		0.1			—
Balance at end of period	$	17.9		$	16.8		$	13.2