CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash Flows from Operating Activities
Net Income	$ 212.6	$ 213.9
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	(130.1)	1.6
Change in Deferred Acquisition Costs	5.6	(18.0)
Change in Insurance Reserves and Liabilities	197.6	167.3
Change in Income Taxes	40.1	116.7
Change in Other Accrued Liabilities	23.4	(68.0)
Non-cash Adjustments to Net Investment Income	(96.1)	(100.9)
Net Realized Investment Gain	(10.3)	(12.4)
Depreciation	21.2	20.5
Other, Net	1.1	8.6
Net Cash Provided by Operating Activities	265.1	329.3
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	158.4	127.6
Proceeds from Maturities of Fixed Maturity Securities	518.5	596.3
Proceeds from Sales and Maturities of Other Investments	42.3	33.5
Purchase of Fixed Maturity Securities	(721.9)	(845.7)
Purchase of Other Investments	(43.4)	(52.6)
Net Sales (Purchases) of Short-term Investments	256.3	(17.2)
Other, Net	(26.1)	(23.7)
Net Cash Provided (Used) by Investing Activities	184.1	(181.8)
Cash Flows from Financing Activities
Net Short-term Debt Borrowings (Payments)	(219.5)	59.9
Long-term Debt Repayments	(71.2)	(17.5)
Issuance of Common Stock	0.7	0.9
Repurchase of Common Stock	(99.0)	(175.2)
Dividends Paid to Stockholders	(35.7)	(31.4)
Other, Net	0.2	1.7
Net Cash Used by Financing Activities	(424.5)	(161.6)
Net Increase (Decrease) in Cash and Bank Deposits	24.7	(14.1)
Cash and Bank Deposits at Beginning of Year	77.3	116.6
Cash and Bank Deposits at End of Period	$ 102.0	$ 102.5