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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) shares in Thousands, $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Decrease accumulated other comprehensive income |  |  |  | $ (8,825) | $ (12,809) | $ (12,707) |
Anticipated amounts due from insureds related to losses under deductible policies |  |  |  | $ 1,100 | $ 1,100 |  |
Structured settlement annuities, interest rate, low end |  |  |  | 6.40% | 6.40% |  |
Discounted reserves for unfunded structured settlements |  |  |  | $ 485 | $ 503 |  |
Discounted reserves for unfunded structure settlements, discount amount |  |  |  | 590 | 621 |  |
Amount of interest recognized on the discounted reserves of unfunded structured settlements |  |  |  | $ 36 | $ 36 | 35 |
Interest rates at which workers' compensation lifetime claim reserves are discounted at |  |  |  | 3.50% | 3.50% |  |
Workers' compensation liability |  |  |  | $ 211 | $ 228 |  |
Discounted reserves for workers’ compensation lifetime claim reserves, discount amount |  |  |  | 93 | 97 |  |
Amount of interest accretion recognized on the discounted reserves of workers’ compensation lifetime claim reserves |  |  |  | $ 9 | $ 12 | $ 15 |
Long term care claim reserves weighted average discounted interest rate |  |  |  | 5.90% | 5.80% |  |
Discounted reserves for long term care claim reserves |  |  |  | $ 2,800 | $ 2,700 |  |
Premium deficiency |  |  |  | $ 450 | $ 428 |  |
Liability for future policy benefits, gross premium valuation, pretax margin | $ 125 | $ 72 | $ 125 |  |  |  |
Minimum interest rate used to calculate reserves for long term care products |  |  |  | 5.30% | 5.30% |  |
Liability balance for guaranty fund |  |  |  | $ 74 | $ 79 |  |
Percentage of billed receivables compared to total reinsurance receivable |  |  |  | 5.00% |  |  |
Policyholder dividends, rate on policy earnings |  |  |  | 2.00% | 1.00% | 1.00% |
Increase (decrease) in shadow adjustment, net of tax |  |  |  | $ 2,416 | $ 296 |  |
Reduction of net unrealized gains on investments included in AOCI due to shadow adjustments |  |  |  | 61 | 2,477 |  |
Foreign currency transaction gain (loss), before tax |  |  |  | $ (22) | $ (1) | $ 13 |
Operating lease, right-of-use asset, statement of financial position [Extensible List] |  |  |  | Other Assets | Other Assets |  |
Operating lease, liability, statement of financial position [Extensible List] |  |  |  | Other liabilities | Other liabilities |  |
Weighted average number diluted shares outstanding adjustment (in shares) |  |  |  | 1,000 | 1,000 | 1,000 |
Interest paid, net |  |  |  | $ 109 | $ 110 | $ 124 |
Income taxes paid |  |  |  | $ 277 | 278 | 108 |
Furniture and Fixtures |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Property, plant and equipment, useful life |  |  |  | 7 years |  |  |
Office Equipment |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Property, plant and equipment, useful life |  |  |  | 5 years |  |  |
Computer Software, Intangible Asset |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Property, plant and equipment, useful life |  |  |  | 10 years |  |  |
Minimum |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Warranty coverage term |  |  |  | 1 month |  |  |
Requisite service period for stock- based compensation expense |  |  |  | 3 years |  |  |
Minimum | Computer Software, Intangible Asset |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Property, plant and equipment, useful life |  |  |  | 3 years |  |  |
Maximum |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Warranty coverage term |  |  |  | 10 years |  |  |
Maximum | Computer Software, Intangible Asset |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Property, plant and equipment, useful life |  |  |  | 5 years |  |  |
CNAF Consolidated | Loews |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Noncontrolling interest, ownership percentage by parent |  |  |  | 90.00% |  |  |
Accumulated Other Comprehensive (Loss) Income |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Decrease accumulated other comprehensive income |  |  |  | $ 3,557 | $ (320) | (803) | $ (51)
Accumulated Other Comprehensive (Loss) Income | Revision of Prior Period, Accounting Standards Update, Adjustment |  |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |  |
Decrease accumulated other comprehensive income |  |  |  |  |  | $ 2,300 |

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Name: | srt_RestatementAxis=srt_RevisionOfPriorPeriodAccountingStandardsUpdateAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |