CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	[1]
Revenues
Net premiums and contract charges earned	$ 1,146.0	$ 1,057.1	$ 1,027.7
Net investment income	445.7	444.8	400.9
Net investment losses	(17.3)	(24.0)	(56.5)
Other income	20.8	14.0	9.5
Revenues, Total	1,595.2	1,491.9	1,381.6
Benefits, losses and expenses
Benefits, claims and settlement expenses (Reserve remeasurement (gains)/losses $1.6, $(1.6), $(2.5))	745.0	769.1	747.0
Interest credited	215.9	205.7	173.4
Operating expenses	345.5	318.1	315.5
DAC amortization expense	111.1	101.2	88.2
Intangible asset amortization expense	14.5	14.8	16.8
Interest expense	34.6	29.7	19.4
Other expense - goodwill and intangible asset impairments	0.0	0.0	4.8
Total benefits, losses and expenses	1,466.6	1,438.6	1,365.1
Income before income taxes	128.6	53.3	16.5
Income tax expense (benefit)	25.8	8.3	(3.3)
Net income	$ 102.8	$ 45.0	$ 19.8
Net income per share
Basic (in usd per share)	$ 2.49	$ 1.09	$ 0.48
Diluted (in usd per share)	$ 2.48	$ 1.09	$ 0.47
Weighted average number of shares and equivalent shares
Basic (in shares)	41.3	41.3	41.6
Diluted (in shares)	41.5	41.4	41.8
Net income	$ 102.8	$ 45.0	$ 19.8
Other comprehensive income (loss), net of tax:
Change in net unrealized investment gains (losses) on fixed maturity securities	(29.1)	121.3	(796.7)
Change in net reserve remeasurements attributable to discount rates	89.0	(37.1)	445.9
Change in net funded status of benefit plans	0.6	1.2	1.4
Other comprehensive income (loss)	60.5	85.4	(349.4)
Total comprehensive income (loss)	$ 163.3	$ 130.4	$ (329.6)

[1] Recast for the adoption of ASU 2018-12.