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v3.25.0.1

Debt (Long-Term Debt) (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Debt Instrument [Line Items] |  |  |
Long-term debt, gross |  | $ 2,741 | $ 2,585
Debt issuance costs |  | (7) | (7)
7.000% Debentures Due 2025 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt, gross |  | $ 45 | 45
Long-term debt, interest rate |  | 7.00% |
Long-term debt, maturity year |  | 2025 |
7.150% Debentures Due 2027 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt, gross |  | $ 95 | 96
Long-term debt, interest rate |  | 7.15% |
Long-term debt, maturity year |  | 2027 |
6.625% Debentures Due 2028 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt, gross |  | $ 112 | 112
Long-term debt, interest rate |  | 6.625% |
Long-term debt, maturity year |  | 2028 |
5.700% Senior Notes Due 2034 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt, gross | [1] | $ 21 | 21
Long-term debt, interest rate |  | 5.70% |
Long-term debt, maturity year |  | 2034 |
Surplus Notes due 2033 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Surplus Notes | [2] | $ 940 | 940
Long-term debt, interest rate |  | 11.52161% |
Long-term debt, maturity year |  | 2033 |
Accrued Interest [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt, gross |  | $ 1,535 | $ 1,378
[1] | Callable anytime at the greater of par or the present value of the remaining scheduled payments of principal and interest.
[2] | Contractual interest rate is based on three-month term Secured Overnight Financing Rate ("SOFR") plus 11.52161% at each future reset date.

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-4 + Details
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