TOTAL INVESTED ASSETS Cash TOTAL ASSETS Other Assets Goodwill Premiums Receivable Reinsurance Recoverable on Unpaid Losses and Loss Expenses Prepaid Reinsurance Premiums Deferred Policy Acquisition Costs Accrued Investment Income Deferred Income Tax Unearned Premiums TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY TOTAL SHAREHOLDERS' EQUITY TOTAL LIABILITIES Long Term Debt Accrued Expenses and Other Liabilities Common Stock - $1 Par Value; 371,980,710 and 374,649,923 Shares Common Stock, Par Value Treasury Stock, Shares Treasury Stock, at Cost - 16,279,184 Shares in 2008 Accumulated Other Comprehensive Income (Loss) Retained Earnings Common Stock, Shares, Issued Investment Income Other Revenues Total Revenues Total Realized Gains (Losses), Net Dividends Declared Per Share Amortization of Deferred Policy Acquisition Costs Income Before Federal and Foreign Income Tax Net Income Basic Diluted Investment Expenses Comprehensive Income Net Income Net Cash Provided by Operating Activities Increase decrease in other operating capital net Depreciation Amortization of Premiums and Discounts on Fixed Maturities Decrease in Unearned Premiums, Net Decrease in Premiums Receivable Net Cash Used in Investing Activities Payments for proceeds from other investing activities Net Cash Used in Financing Activities Proceeds from payments for other financing actitivies Repayment of Long Term Debt Purchases of Equity Securities Other Expenses Total Other Comprehensive Income (Loss), Net of Tax Dividends Paid to Shareholders Repurchase of Shares Proceeds from Issuance of Common Stock Under Stock-Based Employee Compensation Plans This item represents total tax-exempt debt securities that are categorized as neither held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income. Tax Exempt (cost $18,697 and $18,299) This item represents total taxable debt securities that are categorized as neither held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income. Taxable (cost $15,418 and $14,592) This item represents the amortized cost basis of taxable debt securities that are categorized as neither held-to-maturity nor trading. Taxable, Cost This item represents the original cost basis of equity securities. Equity Securities, Cost This item represents the amortized cost basis of tax exempt debt securities that are categorized as neither held-to-maturity nor trading. Tax Exempt, Cost Total Realized Gains (Losses), Net Purchases of Property and Equipment, Net Segments Information Contingent Liabilities Federal and Foreign Income Tax Purchases of Fixed Maturities Proceeds from Issuance of Long Term Debt Balance Sheets [Abstract] Balance Sheets [Abstract] Balance Sheets. Fixed Maturities Fixed Maturities Abstract Fixed Maturities. Shareholders' Equity Liabilities Abstract Assets Abstract Statements of Income [Abstract] Statements of Income [Abstract] Statements of Income. Earnings Per Share [Abstract] Losses and Expenses Revenues Abstract Statements of Comprehensive Income [Abstract] Statements of Comprehensive Income [Abstract] Statements of Comprehensive Income. Other Comprehensive Income (Loss), Net of Tax Statements of Cash Flows [Abstract] Statements of Cash Flows [Abstract] Statements of Cash Flows. Cash Flows from Investing Activities Cash Flows from Financing Activities Cash Flows from Operating Activities Balance Sheets (Parenthetical) [Abstract] Balance Sheets (Parenthetical) [Abstract] Balance Sheets Parenthetical. Document and Company Information [Abstract] Document and Company Information [Abstract] Document and Company Information. Short Term Investments Equity Securities (cost $1,660 and $1,907) Accrued Expenses and Other Liabilities Losses and Loss Expenses Other Insurance Operating Costs and Expenses Proceeds From Sale Of Available For Sale Securities, Debt Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities General [Abstract] General [Abstract] General. Adoption of New Accounting Pronouncements [Abstract] Adoption of New Accounting Pronouncements [Abstract] Adoption of New Accounting Pronouncements. Segments Information [Abstract] Segments Information [Abstract] Segments Information. Contingent Liabilities [Abstract] Contingent Liabilities [Abstract] Contingent Liabilities. Adoption of New Accounting Pronouncements Fixed Maturities Entity Common Stock, Shares Outstanding (actual number of shares) Tax Exempt (cost $18,697 and $18,299) Taxable (cost $15,418 and $14,592) Corporate Expenses Corporate Expenses The total amount of expenses incurred by the entity related to corporate activities, including interest expese. Total Losses and Expenses Total Losses and Expenses The total amount of losses and expenses recognized during the period. Proceeds from Sales of Equity Securities Proceeds from Sale of Available-for-sale Securities, Equity Realized Investment Losses, Net Gain (Loss) on Investments General General Total Losses and Expenses Federal and Foreign Income Tax Income Tax Expense (Benefit) Basic Earnings Per Share, Basic Diluted Earnings Per Share, Diluted Tax Exempt (cost $18,697 and $18,299) Taxable (cost $15,418 and $14,592) Long Term Debt Long-term Debt Retained Earnings Retained Earnings (Accumulated Deficit), Beginning Balance Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit) Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax Net Income Other Comprehensive Income (Loss), Net of Tax, Total Other Comprehensive Income (Loss), Net of Tax, Period Increase (Decrease) Purchases of Property and Equipment, Net Payments to Acquire Property, Plant, and Equipment Proceeds from Issuance of Long Term Debt Proceeds from Issuance of Long-term Debt Repayment of Long Term Debt Repayments of Long-term Debt Proceeds from Issuance of Common Stock Under Stock-Based Employee Compensation Plans Other Invested Assets Other Invested Assets This item represents other invested assets, including private equity limited partnerships, which are carried at the Corporation's equity in the net assets of the partnerships. Unpaid Losses and Loss Expenses Liability for Claims and Claims Adjustment Expense, Property Casualty Liability Paid-In Surplus Additional Paid in Capital, Total Additional Paid in Capital, Beginning Balance Additional Paid in Capital, Ending Balance Additional Paid in Capital Investments in Other Invested Assets, Net Payments for (Proceeds from) Limited Partnership Increase in Short Term Investments, Net Payments for (Proceeds from) Short-term Investments, Total Payments for (Proceeds from) Short-term Investments Increase in Net Payable from Security Transactions Not Settled Increase in Net Payable from Security Transactions Not Settled Change in net receivable or payable from security transactions not settled. Premiums Earned Premiums Earned, Net, Property and Casualty, Total Premiums Earned, Net, Property and Casualty Other, Net Other, Net Other, Net Corporate Expenses Income Before Federal and Foreign Income Tax Income (Loss) from Continuing Operations before Income Taxes, Minority Interest, and Income (Loss) from Equity Method Investments Other Invested Assets TOTAL INVESTED ASSETS Investments Other Assets Accrued Expenses and Other Liabilities Treasury Stock, at Cost XX,XXX,XXX and 19,726,097 Shares Treasury Stock, Value, Beginning Balance Treasury Stock, Value, Ending Balance TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Stockholders' Equity Realized Investment Losses, Net Increase in Unpaid Losses and Loss Expenses, Net Increase (Decrease) in Property and Casualty Insurance Liabilities Treasury Stock, at Cost - 22,079,150 and 19,726,097 Shares Proceeds from Issuance of Long Term Debt Proceeds from Issuance of Common Stock Under Stock-Based Employee Compensation Plans Other, Net Increase in Net Payable from Security Transactions Not Settled Increase in Short Term Investments, Net Net Cash Used in Investing Activities Net Cash Provided by (Used in) Investing Activities Purchases of Fixed Maturities Purchases of Equity Securities Other, Net Purchases of Property and Equipment, Net Repayment of Long Term Debt Repurchase of Shares Dividends Paid to Shareholders Other, Net Net Cash Used in Investing Activities Common Stock, Shares Issued Common Stock, Shares, Issued, Total Treasury Stock, Shares Treasury Stock, Shares, Beginning Balance Treasury Stock, Shares, Ending Balance Investments in Other Invested Assets, Net Equity Securities (cost $1,235 and $1,563) Cash Accrued Investment Income Accrued Investment Income Receivable, Total Premiums Receivable Premiums Receivable, at Carrying Value, Total Reinsurance Recoverable on Unpaid Losses and Loss Expenses Prepaid Reinsurance Premiums Deferred Policy Acquisition Costs Deferred Policy Acquisition Costs, Total Deferred Income Tax Deferred Tax Assets, Net, Total Goodwill Goodwill, Beginning Balance Goodwill, Ending Balance Assets Liabilities Unearned Premiums Unearned Premiums, Total Shareholders' Equity Common Stock - $1 Par Value; 371,980,710 Shares Common Stock, Value, Total Common Stock, Value, Beginning Balance Common Stock, Value, Ending Balance Treasury Stock, at Cost XX,XXX,XXX and 19,726,097 Shares Invested Assets [Abstract] Invested Assets [Abstract] Invested Assets. Fair Values Of Financial Instruments [Abstract] Fair Values Of Financial Instruments [Abstract] Fair Values Of Financial Instruments. Fair Values of Financial Instruments Fair Value Disclosures [Text Block] Cash Flows from Operating Activities Increase (Decrease) in Unearned Premiums, Net Increase in Premiums Receivable Amortization of Premiums and Discounts on Fixed Maturities Depreciation Cash Flows from Investing Activities Proceeds from Fixed Maturities - Sales Proceeds from Fixed Maturies - Maturities, Calls and Redemptions Purchases of Fixed Maturities Purchases of Equity Securities Other, Net Repurchase of Shares Dividends Paid to Shareholders Short Term Investments Revenues Investment Income Interest and Dividend Income, Operating, Total Other Revenues Losses and Expenses Losses and Loss Expenses Amortization of Deferred Policy Acquisition Costs Deferred Policy Acquisition Cost, Amortization Expense, Total Other Insurance Operating Costs and Expenses Investment Expenses Other Expenses Other Nonoperating Expense, Total Net Income Per Share Dividends Declared Per Share Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Contingent Liabilities Commitments and Contingencies Cash Flows from Financing Activities Other Comprehensive Income (Loss), Net of Tax Common Stock, Par Value Equity Securities, Cost Taxable, Cost Tax Exempt, Cost Comprehensive Income, Net of Tax, Attributable to Parent Change in Unrealized Other-Than-Temporary Impairment Losses on Investments Change in Unrealized Other-Than-Temporary Impairments of Investments This item represents the non-credit impairment losses portion of other-than-temporary impairments on fixed maturity investments in which a credit loss was recognized in the Consolidated Statements of Income. This item includes the impact of subsequent changes to these securities such as appreciation or loss in value or subsequent sale of the security. Realized Gains (Losses), Net Realized Gains Losses Net Abstract Realized Gains (Losses), Net. Change In Net Payable Receivable From Security Transactions Not Settled Other Realized Gains (Losses), Net Other Realized Gains (Losses), Net This item represents the net total realized gain (loss) included in earnings for the period as a result of selling or holding invested assets. Total Realized Gains (Losses), Net Total Other-than-Temporary Impairment Losses on Investments Other Realized Gains (Losses), Net Total Realized Gains (Losses), Net Earnings Per Share Earnings Per Share [Text Block] Invested Assets Available-for-sale Securities [Text Block] Net Cash Used in Financing Activities Net Cash Provided by (Used in) Financing Activities Net Cash Provided by Operating Activities Net Cash Provided by (Used in) Operating Activities Other-than-Temporary Impairment Losses on Investments Recognized in Other Comprehensive Income Other than Temporary Impairment Losses on Investments Recognized in Other Comprehensive Income This item represents the non-credit impairment loss portion of the total other-than-temporary impairment losses on investments for fixed maturity investments that the Corporation does not intend to sell or it is not more likely than not the Corporation will be required to sell these securities before they recover to their amortized cost value. This amount offsets the amount included in the total other-than-temporary impairment losses on investments and recognized in accumulated other comprehensive income. Dividend Payable to Shareholders Dividends Payable Change in Unrealized Appreciation or Depreciation of Investments Other Comprehensive Income, Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent, Total Other Comprehensive Income, Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Change in Unrealized Other-Than-Temporary Impairments Losses on Investments Foreign Currency Translation Gains (Losses) Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent, Total Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Amortization of Net Loss and Prior Service Cost Included in Net Postretirement Benefit Costs Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax, Portion Attributable to Parent Total Other-Than-Temporary Impairment Losses on Investments Other-Than-Temporary Impairment Losses on Investments Recognized in Other Comprehensive Income Adoption of New Accounting Pronouncements Segments Information Contingent Liabilities Cash at Beginning of Year Cash at End of Period Document and Company Information [Abstract] Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Amendment Description Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Statement [Table] Statement [Line Items] Revenues Tax Exempt Taxable Assets Liabilities Stockholders' Equity Attributable to Parent Change In Unrealized Other Than Temporary Impairments Of Investments Net Increase in Cash Cash Period Increase Decrease The net change between the beginning and ending balance of unrestricted cash available for day-to-day operating needs. Invested Assets Investments [Abstract] Proceeds from Fixed Maturities Proceeds from Sale of Available-for-sale Securities [Abstract]