CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash Flows from Operating Activities
Net Income	$ 430.3	$ 451.2
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	70.6	88.4
Change in Deferred Acquisition Costs	(38.0)	(35.0)
Change in Insurance Reserves and Liabilities	311.7	221.9
Change in Income Taxes	134.7	41.3
Change in Other Accrued Liabilities	(65.1)	31.0
Non-cash Adjustments to Net Investment Income	(203.5)	(215.8)
Net Realized Investment Gain (Loss)	(10.3)	(11.6)
Depreciation	41.2	39.7
Other, Net	7.5	4.6
Net Cash Provided by Operating Activities	679.1	615.7
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	242.2	585.5
Proceeds from Maturities of Fixed Maturity Securities	1,041.9	905.5
Proceeds from Sales and Maturities of Other Investments	76.7	69.2
Purchase of Fixed Maturity Securities	(1,640.8)	(1,588.1)
Purchase of Other Investments	(167.5)	(165.1)
Net Sales (Purchases) of Short-term Investments	(28.8)	196.2
Other, Net	(44.6)	(49.4)
Net Cash Used by Investing Activities	(520.9)	(46.2)
Cash Flows from Financing Activities
Net Short-term Debt Borrowings (Repayments)	154.8	(84.7)
Long-term Debt Repayments	(34.2)	(49.4)
Issuance of Common Stock	2.9	6.9
Repurchase of Common Stock	(300.3)	(369.7)
Dividends Paid to Stockholders	(61.6)	(58.3)
Other, Net	1.6	3.3
Net Cash Used by Financing Activities	(236.8)	(551.9)
Net Increase (Decrease) in Cash and Bank Deposits	(78.6)	17.6
Cash and Bank Deposits at Beginning of Year	116.6	53.6
Cash and Bank Deposits at End of Period	$ 38.0	$ 71.2