Disclosures about Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Summary of Company's Financial Instruments Whose Carrying Amount Did Not Equal Fair Value

A summary of our financial instruments whose carrying value did not equal fair value is shown below:

	March 31, 2022				December 31, 2021
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Junior subordinated debentures:
Trust preferred debentures	$	172.7	$	173.2	$	172.7	$	172.9
Subordinated debentures	85.6		92.1		85.5		91.9
Total junior subordinated debentures	258.3		265.3		258.2		264.8
Senior unsecured fixed rate notes	140.4		144.1		140.3		148.4
Floating rate loan stock	57.3		57.4		57.0		57.1
	$	456.0	$	466.8	$	455.5	$	470.3

Fair Value, Assets Measured on Recurring and Nonrecurring Basis

Based on an analysis of the inputs, our financial instruments measured at fair value for disclosure purposes have been categorized as follows:

	Fair Value Measurements at Reporting Date Using
(in millions)	March 31, 2022		Level 1 (a)		Level 2 (b)		Level 3 (c)
Junior subordinated debentures:
Trust preferred debentures	$	173.2	$	—	$	173.2	$	—
Subordinated debentures	92.1		—		92.1		—
Total junior subordinated debentures	265.3		—		265.3		—
Senior unsecured fixed rate notes	144.1		144.1		—		—
Floating rate loan stock	57.4		—		57.4		—
	$	466.8	$	144.1	$	322.7	$	—

(a)Quoted prices in active markets for identical assets

(b)Significant other observable inputs

(c)Significant unobservable inputs

	Fair Value Measurements at Reporting Date Using
(in millions)	December 31, 2021		Level 1 (a)		Level 2 (b)		Level 3 (c)
Junior subordinated debentures:
Trust preferred debentures	$	172.9	$	—	$	172.9	$	—
Subordinated debentures	91.9		—		91.9		—
Total junior subordinated debentures	264.8		—		264.8		—
Senior unsecured fixed rate notes	148.4		148.4		—		—
Floating rate loan stock	57.1		—		57.1		—
	$	470.3	$	148.4	$	321.9	$	—

(a)Quoted prices in active markets for identical assets

(b)Significant other observable inputs

(c)Significant unobservable inputs