Consolidated Statements of Comprehensive Income - USD ($) shares in Millions, $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenues
Net premiums earned		$ 12,147.9	$ 10,982.3	$ 23,950.8	$ 21,402.5
Investment income		292.4	210.7	534.6	430.9
Net realized gains (losses) on securities:
Net realized gains (losses) on security sales		546.6	410.1	492.1	553.9
Net holding period gains (losses) on securities		(1,722.2)	54.2	(2,110.8)	495.7
Net impairment losses recognized in earnings		(2.1)	(2.5)	(4.3)	(2.5)
Total net realized gains (losses) on securities		(1,177.7)	461.8	(1,623.0)	1,047.1
Fees and other revenues		176.5	176.2	350.5	341.9
Service revenues		80.1	74.5	147.8	128.3
Total revenues		11,519.2	11,905.5	23,360.7	23,350.7
Expenses
Losses and loss adjustment expenses		9,421.1	8,406.4	18,279.5	15,516.9
Policy acquisition costs		933.6	928.8	1,897.0	1,803.2
Other underwriting expenses		1,431.2	1,440.5	2,937.5	2,921.6
Investment expenses		5.9	6.3	11.6	11.9
Service expenses		75.5	67.9	138.7	117.2
Interest expense		63.0	56.4	117.3	112.8
Goodwill impairment	[1]	224.8	0.0	224.8	0.0
Total expenses		12,155.1	10,906.3	23,606.4	20,483.6
Net Income (Loss)
Income (loss) before income taxes		(635.9)	999.2	(245.7)	2,867.1
Provision (benefit) for income taxes		(93.0)	209.1	(16.7)	597.0
Net income (loss)		(542.9)	790.1	(229.0)	2,270.1
Other Comprehensive Income (Loss)
Total net unrealized gains (losses) on fixed-maturity securities		(822.8)	91.1	(2,249.7)	(448.5)
Net unrealized losses on forecasted transactions		0.0	0.3	0.2	0.5
Foreign currency translation adjustment		(0.4)	(0.5)	(0.2)	(0.5)
Other comprehensive income (loss)		(823.2)	90.9	(2,249.7)	(448.5)
Comprehensive income (loss)		(1,366.1)	881.0	(2,478.7)	1,821.6
Computation of Earnings Per Common Share
Net income (loss)		(542.9)	790.1	(229.0)	2,270.1
Less: Preferred share dividends		6.7	6.7	13.4	13.4
Net income (loss) available to common shareholders		$ (549.6)	$ 783.4	$ (242.4)	$ 2,256.7
Average common shares outstanding - Basic		584.3	584.6	584.3	584.7
Net effect of dilutive stock-based compensation		2.2	2.2	2.1	2.1
Total average equivalent common shares - Diluted		586.5	586.8	586.4	586.8
Basic: Earnings per common share		$ (0.94)	$ 1.34	$ (0.41)	$ 3.86
Diluted: Earnings per common share		$ (0.94)	$ 1.34	$ (0.41)	$ 3.85

[1] See Note 12 – Goodwill and Intangible Assets for further discussion.