CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net Income	$ 413.4us-gaap_NetIncomeLoss	$ 858.1us-gaap_NetIncomeLoss	$ 894.4us-gaap_NetIncomeLoss
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	(21.5)us-gaap_IncreaseDecreaseInReceivables	(196.7)us-gaap_IncreaseDecreaseInReceivables	40.4us-gaap_IncreaseDecreaseInReceivables
Change in Deferred Acquisition Costs	(83.2)	(47.9)	(88.6)
Change in Insurance Reserves and Liabilities	972.2	572.5	508.4
Change in Income Taxes	(44.7)	(49.4)	168.0
Change in Other Accrued Liabilities	105.2	21.2	18.6
Non-cash Components of Net Investment Income	(180.9)	(211.5)	(221.3)
Net Realized Investment Gain	(16.1)us-gaap_GainLossOnInvestments	(6.8)us-gaap_GainLossOnInvestments	(56.2)us-gaap_GainLossOnInvestments
Depreciation	87.9	84.8	84.3
Other, Net	(8.7)us-gaap_OtherNoncashIncomeExpense	7.2us-gaap_OtherNoncashIncomeExpense	31.6us-gaap_OtherNoncashIncomeExpense
Net Cash Provided by Operating Activities	1,223.6	1,031.5	1,379.6
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	450.1	1,040.5	595.9
Proceeds from Maturities of Fixed Maturity Securities	1,819.4	2,146.4	2,160.5
Proceeds from Sales and Maturities of Other Investments	235.0	243.4	182.2
Purchase of Fixed Maturity Securities	(2,918.4)	(3,553.6)	(3,512.8)
Purchase of Other Investments	(285.2)	(363.7)	(353.8)
Net Sales (Purchases) of Short-term Investments	(69.3)	551.3	(34.5)
Net Increase (Decrease) in Payables for Collateral on Investments	(3.8)	(378.2)	97.9
Net Purchases of Property and Equipment	(114.5)	(105.5)	(105.4)
Other, Net	0.1	0.2	0.1
Net Cash Used by Investing Activities	(886.6)	(419.2)	(969.9)
Cash Flows from Financing Activities
Issuance of Long-term Debt	347.2	0	246.4
Long-term Debt Repayments	(186.6)us-gaap_RepaymentsOfLongTermDebt	(116.2)us-gaap_RepaymentsOfLongTermDebt	(70.0)us-gaap_RepaymentsOfLongTermDebt
Cost Related to Early Retirement of Debt	(13.2)	0	0
Issuance of Common Stock	12.3	11.4	4.9
Repurchase of Common Stock	(306.0)	(317.2)	(496.7)
Dividends Paid to Stockholders	(159.4)us-gaap_PaymentsOfDividends	(146.5)us-gaap_PaymentsOfDividends	(133.8)us-gaap_PaymentsOfDividends
Other, Net	(22.9)	(27.0)	0.2
Net Cash Used by Financing Activities	(328.6)	(595.5)	(449.0)
Net Increase (Decrease) in Cash and Bank Deposits	8.4	16.8	(39.3)
Cash and Bank Deposits at Beginning of Year	94.1us-gaap_Cash	77.3us-gaap_Cash	116.6us-gaap_Cash
Cash and Bank Deposits at End of Year	$ 102.5us-gaap_Cash	$ 94.1us-gaap_Cash	$ 77.3us-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

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-Number 210

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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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-SubTopic 10

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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.

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

-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