Basis of Presentation (Tables)

6 Months Ended

Jun. 30, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Premium Receivable, Allowance for Credit Loss

The following table summarizes changes in our allowance for credit loss exposure on our premiums receivables:

	Three Months				Six Months
Periods Ended June 30,	2021		2020		2021		2020
(millions)
Allowance for credit loss, beginning of period	$	265.3	$	344.7	$	356.2	$	283.2
Allowance acquired during period1	3.5		0		3.5		0
Increase in allowance2	87.4		196.2		148.3		366.5
Write-offs3	(111.0)		(103.0)		(262.8)		(211.8)
Allowance for credit loss, end of period	$	245.2	$	437.9	$	245.2	$	437.9

1 Represents the amount of the allowance acquired in the Protective Insurance acquisition.

2 Represents the incremental increase in other underwriting expenses.

3 Represents portion of allowance that is reversed when premiums receivables are written off.