CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash Flows from Operating Activities
Net Income	$ 212.9us-gaap_NetIncomeLoss	$ 225.8us-gaap_NetIncomeLoss
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	49.2us-gaap_IncreaseDecreaseInReceivables	14.0us-gaap_IncreaseDecreaseInReceivables
Change in Deferred Acquisition Costs	(10.7)	(10.4)
Change in Insurance Reserves and Liabilities	98.4	120.6
Change in Income Taxes	161.4	142.9
Change in Other Accrued Liabilities	(69.0)	(62.6)
Non-cash Components of Net Investment Income	(90.5)	(100.0)
Net Realized Investment (Gain) Loss	15.3us-gaap_GainLossOnInvestments	(6.3)us-gaap_GainLossOnInvestments
Depreciation	23.5	20.8
Other, Net	9.6us-gaap_OtherNoncashIncomeExpense	1.9us-gaap_OtherNoncashIncomeExpense
Net Cash Provided by Operating Activities	400.1	346.7
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	108.5	193.4
Proceeds from Maturities of Fixed Maturity Securities	468.0	510.0
Proceeds from Sales and Maturities of Other Investments	42.5	57.4
Purchase of Fixed Maturity Securities	(959.5)	(904.4)
Purchase of Other Investments	(127.6)	(95.6)
Net Sales (Purchases) of Short-term Investments	259.8	(275.0)
Increase (Decrease) in Payables for Collateral on Investments	6.1	(13.2)
Net Purchases of Property and Equipment	(31.4)	(28.1)
Net Cash Used by Investing Activities	(233.6)	(555.5)
Cash Flows from Financing Activities
Issuance of Long-term Debt	0	347.2
Long-term Debt Repayments	(29.1)us-gaap_RepaymentsOfLongTermDebt	(15.0)us-gaap_RepaymentsOfLongTermDebt
Issuance of Common Stock	0.8	1.6
Repurchase of Common Stock	(108.1)	(100.5)
Dividends Paid to Stockholders	(42.3)us-gaap_PaymentsOfDividends	(38.3)us-gaap_PaymentsOfDividends
Other, Net	(6.2)	(4.1)
Net Cash Provided (Used) by Financing Activities	(184.9)	190.9
Net Decrease in Cash and Bank Deposits	(18.4)	(17.9)
Cash and Bank Deposits at Beginning of Year	102.5us-gaap_Cash	94.1us-gaap_Cash
Cash and Bank Deposits at End of Period	$ 84.1us-gaap_Cash	$ 76.2us-gaap_Cash

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Section S99

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 10

-Section 45

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Total net Increase or Decrease in changes to deferred policy acquisition costs due to one or more transactions, including amortization of costs and modifications or internal replacements of existing insurance contracts.

+ References

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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

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-Publisher FASB

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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The increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction.

+ References