| **Schedule II. Condensed Financial Information of Registrant (Parent Company) (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Condensed Financial Information of Parent Company Only Disclosure [Abstract]**         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Condensed Financial Information of Registrant, Statements of Operations      | Statements of OperationsYears ended December 31     (In millions)2011 2010 2009Revenues     Net investment income$1 $4 $3Net realized investment gains (losses)(9) (1) 8Other income40 96 101Total revenues32 99 112Expenses     Administrative and general3 5 2Interest167 148 116Total expenses170 153 118Loss from operations before income taxes and equity in net income of subsidiaries(138) (54) (6)Income tax benefit46 19 2Loss before equity in net income of subsidiaries(92) (35) (4)Equity in net income of subsidiaries706 725 423Net income$614 $690 $419                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Schedule of Condensed Financial Information of Registrant, Balance Sheets                | Balance SheetsDecember 31   (In millions, except share data)2011 2010Assets   Investment in subsidiaries$13,564 $12,780Fixed maturity securities available-for-sale, at fair value (amortized cost of $2 and $3)2 3Short term investments292 215Amounts due from subsidiaries— 11Surplus note due from subsidiary250 500Other assets18 16Total assets$14,126 $13,525Liabilities and equity   Liabilities:   Short term debt$3 $399Long term debt2,525 2,131Other liabilities41 41Total liabilities2,569 2,571Equity:   Common stock ($2.50 par value; 500,000,000 shares authorized; 273,040,243 shares issued;  269,274,900 and 269,139,198 shares outstanding)683 683Additional paid-in capital2,146 2,200Retained earnings8,382 7,876Accumulated other comprehensive income470 326Treasury stock (3,765,343 and 3,901,045 shares), at cost(102) (105)Notes receivable for the issuance of common stock(22) (26)Total equity11,557 10,954Total liabilities and equity$14,126 $13,525                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Schedule of Condensed Financial Information of Registrant, Statements of Cash Flows      | Statements of Cash FlowsYears ended December 31     (In millions)2011 2010 2009Cash Flows from Operating Activities     Net income$614 $690 $419Adjustments to reconcile net income to net cash flows provided (used) by operating activities:     Equity in net income of subsidiaries(706) (725) (423)Dividends received from subsidiaries— 1 —Net realized investment (gains) losses9 1 (8)Other, net55 85 (21)Total adjustments(642) (638) (452)Net cash flows provided (used) by operating activities$(28) $52 $(33)Cash Flows from Investing Activities     Proceeds from fixed maturity securities$1 $(2) $12Change in short term investments(77) 181 145Capital contributions to subsidiaries(38) (6) (3)Return of capital from subsidiaries6 — —Repayment of surplus note by subsidiary250 500 —Other, net1 — (12)Net cash flows provided by investing activities$143 $673 $142Cash Flows from Financing Activities     Dividends paid to common stockholders$(108) $— $—Dividends paid to Loews for 2008 Senior Preferred— (76) (122)Payment to redeem 2008 Senior Preferred— (1,000) (250)Proceeds from the issuance of debt396 495 350Repayment of debt(409) (150) (100)Stock options exercised5 3 1Other, net1 3 12Net cash flows used by financing activities$(115) $(725) $(109)Net change in cash$— $— $—Cash, beginning of year— — —Cash, end of year$— $— $— |
| Schedule of Long Term Debt of Registrant                                                 | DebtDecember 31   (In millions)2011 2010Short term debt:   Senior notes:   6.000%, face amount of $400, due August 15, 2011$— $399Other debt3 —Total short-term debt3 399Long term debt:   Senior notes:   5.850%, face amount of $549, due December 15, 2014548 5486.500%, face amount of $350, due August 15, 2016348 3476.950%, face  amount of $150, due January 15, 2018149 1497.350%, face amount of $350, due November 15, 2019348 3485.875%, face amount of $500, due August 15, 2020495 4955.750%, face amount of $400, due August 15, 2021396 —Debenture, 7.250%, face amount of $243, due November 15, 2023241 241Other debt— 3Total long term debt2,525 2,131Total debt$2,528 $2,530                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |

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