CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash Flows from Operating Activities
Net Income	$ 559.0	$ 475.0
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	52.3	94.8
Change in Deferred Acquisition Costs	(43.3)	(35.5)
Change in Insurance Reserves and Liabilities	291.3	244.1
Change in Income Taxes	(5.5)	55.7
Change in Other Accrued Liabilities	(34.9)	(12.6)
Non-cash Components of Net Investment Income	(185.5)	(213.4)
Net Realized Investment (Gain) Loss	4.8	(19.1)
Depreciation	49.5	53.4
Other, Net	8.5	6.9
Net Cash Provided by Operating Activities	696.2	649.3
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	287.2	272.2
Proceeds from Maturities of Fixed Maturity Securities	1,523.6	1,288.4
Proceeds from Sales and Maturities of Other Investments	257.4	99.5
Purchases of Fixed Maturity Securities	1,931.3	1,384.6
Purchases of Other Investments	(308.9)	(179.9)
Net Purchases of Short-term Investments	(281.5)	(330.3)
Net Decrease in Payables for Collateral on Investments	(88.5)	(1.2)
Net Purchases of Property and Equipment	(59.6)	(47.8)
Net Cash Used by Investing Activities	(601.6)	(283.7)
Cash Flows from Financing Activities
Issuance of Long-term Debt	290.7	0.0
Long-term Debt Repayments	(30.0)	(33.5)
Issuance of Common Stock	2.6	1.5
Repurchase of Common Stock	(205.8)	(207.0)
Dividends Paid to Stockholders	(103.3)	(92.3)
Other, Net	(26.7)	(17.7)
Net Cash Used by Financing Activities	(72.5)	(349.0)
Net Increase in Cash and Bank Deposits	22.1	16.6
Cash and Bank Deposits at Beginning of Year	77.4	100.4
Cash and Bank Deposits at End of Period	$ 99.5	$ 117.0