Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Revenues
Premiums	$ 1,508.5	$ 1,448.6
Net investment income	106.1	89.7
Net realized and unrealized investment gains (losses):
Net realized losses from sales and other	(18.8)	(1.3)
Net change in fair value of equity securities and other	1.0	6.5
Credit-related recoveries on investments		0.3
Total net realized and unrealized investment gains (losses)	(17.8)	5.5
Fees and other income	6.4	7.3
Total revenues	1,603.2	1,551.1
Losses and expenses
Losses and loss adjustment expenses	955.3	935.2
Amortization of deferred acquisition costs	313.9	299.0
Interest expense	8.5	8.5
Other operating expenses	165.4	163.1
Total losses and expenses	1,443.1	1,405.8
Income before income taxes	160.1	145.3
Income tax expense:
Current	30.0	28.7
Deferred	1.9	1.1
Total income tax expense	31.9	29.8
Net income	$ 128.2	$ 115.5
Basic:
Net income per share	$ 3.56	$ 3.22
Weighted average shares outstanding	36.0	35.8
Diluted:
Net income per share	$ 3.50	$ 3.18
Weighted average shares outstanding	36.6	36.3