| **Condensed Consolidated Balance Sheet (Unaudited) Parentheticals (USD $)In Millions, unless otherwise specified** | Sep. 30, 2013 | Dec. 31, 2012 |
|--------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Balance Sheets Parenthetical [Abstract]**                                                                        |          |          |
| Fixed maturities securities at amortized cost                                                                      | $ 39,129      | $ 38,170      |
| Equity securities at cost                                                                                          | 189           | 228           |
| Allowance for uncollectible reinsurance receivables                                                                | 72            | 73            |
| Allowance for uncollectible insurance receivables                                                                  | 90            | 101           |
| Accumulated depreciation on property and equipment                                                                 | 358           | 404           |
| Other assets receivable from Loews Corporation                                                                     |     | 4             |
| Other liabilities payable to Loews Corporation                                                                     | $ 129         |     |
| Common stock, par value                                                                                            | $ 2.50        | $ 2.50        |
| Common stock, shares authorized                                                                                    | 500,000,000   | 500,000,000   |
| Common stock, shares issued                                                                                        | 273,040,243   | 273,040,243   |
| Common stock, shares outstanding                                                                                   | 269,701,999   | 269,399,390   |
| Treasury stock, shares                                                                                             | 3,338,244     | 3,640,853     |

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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Allowance for uncollectible insurance receivables
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Allowance for uncollectible reinsurance receivables
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| - Definition
Marketable securities, fixed maturities, at amortized cost
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.
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| - Definition
This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.
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| - Definition
Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.
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| - Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
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| - Definition
Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.
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| - Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount as of the balance sheet date of obligations due all related parties.
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| - Definition
Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.
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