CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Cash Flows from Operating Activities
Net Income	$ 524.7	$ 784.7
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	360.2	264.5
Deferred Policy Acquisition Cost	(89.9)	(77.9)
Change in Insurance Liabilities	55.0	(123.3)
Change in Income Taxes	10.3	(34.4)
Change in Other Accrued Liabilities	(266.3)	(118.0)
Non-cash Components of Net Investment Income	(176.8)	(194.9)
Net Investment Loss	224.5	11.6
Depreciation	60.2	59.3
Amortization of the Cost of Reinsurance	19.3	20.7
Other, Net	(19.6)	45.1
Net Cash Provided by Operating Activities	701.6	637.4
Cash Flows from Investing Activities
Proceeds from Sale of Debt Securities, Available-for-sale	470.9	249.1
Proceeds from Maturities of Fixed Maturity Securities	923.3	618.0
Proceeds from Sales and Maturities of Other Investments	246.9	160.7
Payments to Acquire Debt Securities, Available-for-sale	(904.3)	(1,023.2)
Purchases of Other Investments	(202.6)	(149.4)
Net Sales and Maturities (Purchases) of Short-term Investments	328.1	(146.5)
Net Increase in Payables for Collateral on Investments	162.1	73.9
Net Purchases of Property and Equipment	(63.7)	(56.0)
Net Cash Provided (Used) by Investing Activities	960.7	(273.4)
Cash Flows from Financing Activities
Issuance of Long-term Debt	0.0	391.6
Repayments of Long-term Debt	0.0	350.0
Issuance of Common Stock	2.8	3.4
Repurchase of Common Stock	(500.9)	(300.0)
Dividends Paid to Stockholders	(150.5)	(141.5)
Proceeds from Policyholder Account Deposits	63.3	67.8
Payments for Policyholder Account Withdrawals	(43.2)	(44.5)
Other, Net	(1.8)	(4.1)
Net Cash Used by Financing Activities	(630.3)	(377.3)
Net Increase (Decrease) in Cash and Bank Deposits	1,032.0	(13.3)
Cash and Bank Deposits at Beginning of Year	162.8	146.0
Cash and Bank Deposits at End of Period	$ 1,194.8	$ 132.7