Schedule of Effect of Change in Discount Rate Assumptions on the Liability for Future Policy Benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Future Policy Benefits
Schedule of Effect of Change in Discount Rate Assumptions on the Liability for Future Policy Benefits
Beginning of Period Balance	$ 445.0	$ (12,565.6)
OCI, Liability for Future Policy Benefit, Gain (Loss), after Reclassification Adjustment and Tax	(882.9)	5,396.8
End of Period Balance	(437.9)	(7,168.8)
Reinsurance Recoverable
Schedule of Effect of Change in Discount Rate Assumptions on the Liability for Future Policy Benefits
Beginning of Period Balance	(748.4)	992.5
OCI, Liability for Future Policy Benefit, Gain (Loss), after Reclassification Adjustment and Tax	156.1	(755.9)
End of Period Balance	(592.3)	236.6
Income Tax
Schedule of Effect of Change in Discount Rate Assumptions on the Liability for Future Policy Benefits
Beginning of Period Balance	617.3	3,002.4
OCI, Liability for Future Policy Benefit, Gain (Loss), after Reclassification Adjustment and Tax	152.9	(982.8)
End of Period Balance	770.2	2,019.6
Effect of Change in Discount Rate Assumptions on the LFPB1
Schedule of Effect of Change in Discount Rate Assumptions on the Liability for Future Policy Benefits
Beginning of Period Balance	313.9	(8,570.7)
OCI, Liability for Future Policy Benefit, Gain (Loss), after Reclassification Adjustment and Tax	(573.9)	3,658.1
End of Period Balance	$ (260.0)	$ (4,912.6)