Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Investments:
Fixed maturities available-for-sale, at fair value (cost: 2022 - $3,016.4, 2021 - $4,203.2; allowance for expected credit losses: 2022 - $2.8, 2021 - $2.5)	$ 2,675.5	$ 4,223.3
Commercial mortgage loans (cost: 2022 - $159.9; allowance for expected credit losses: 2022 - $0.2)	159.7	0.0
Equity securities, at fair value (cost: 2022 - $54.7; 2021 - $70.3)	43.9	56.3
Other investments (cost: 2022 - $323.2; 2021 - $387.0)	323.2	387.2
Short-term investments, at fair value (cost: 2022 - $449.4; 2021 - $655.4)	449.6	655.8
Investments	3,651.9	5,322.6
Cash	50.2	146.1
Accrued investment income	18.6	20.9
Premiums receivable	292.0	648.6
Reinsurance recoverables	3,029.1	2,966.4
Goodwill	118.6	147.3
Intangible assets, net of accumulated amortization	0.0	17.3
Current income taxes receivable, net	44.9	7.3
Deferred tax assets, net	101.2	73.6
Deferred acquisition costs, net	107.0	168.0
Ceded unearned premiums	375.5	506.7
Operating lease right-of-use assets	57.7	81.4
Other assets	121.5	211.6
Assets held-for-sale	2,066.2	0.0
Total assets	10,034.4	10,317.8
Liabilities and Shareholders' Equity
Reserves for losses and loss adjustment expenses	5,051.6	5,595.0
Unearned premiums	1,039.9	1,466.8
Accrued underwriting expenses and other liabilities	121.3	166.6
Ceded reinsurance payable, net	158.7	724.4
Funds held	50.0	76.6
Senior unsecured fixed rate notes	140.5	140.3
Other indebtedness	0.0	57.0
Junior subordinated debentures	258.6	258.2
Operating lease liabilities	66.4	97.7
Liabilities held-for-sale	1,914.5	0.0
Total liabilities	8,801.5	8,582.6
Commitments and contingencies (Note 18)
Shareholders' equity:
Preferred shares and additional paid-in capital - $1.00 par, 30,000,000 shares authorized; 6,000 and 6,000 shares issued at December 31, 2022 and December 31, 2021, respectively; liquidation preference $25,000	144.0	144.0
Common shares - $1.00 par, 500,000,000 shares authorized; 46,379,297 and 46,192,867 shares issued at December 31, 2022 and December 31, 2021, respectively	46.4	46.2
Additional paid-in capital	1,395.4	1,386.4
Treasury shares (11,318,339 and 11,315,889 shares at December 31, 2022 and December 31, 2021, respectively)	(455.1)	(455.1)
Retained earnings	407.3	636.4
Accumulated other comprehensive loss, net of taxes	(305.1)	(22.7)
Total shareholders' equity	1,232.9	1,735.2
Total liabilities and shareholders' equity	$ 10,034.4	$ 10,317.8
Treasury shares (in shares)	11,318,339	11,315,889