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Fair Value of Financial Instruments (Fair Value Hierarchy Table Presents The Company's Assets And Liabilities At Fair Value Not Recorded On The Company's Consolidated Balance Sheet) (Detail) - Value Disclosed At Fair Value Not Recorded At Fair Value [Member] - Fair Value Measurements Nonrecurring [Member] - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Carrying Reported Amount Fair Value Disclosure [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Other investments | $ 3 |
Total assets | 3 |
Long-term debt | 2,546 | $ 2,428
Medium-term notes | 457 | 458
Investment agreements | 225 | 233
Variable interest entity loans payable | 3 | 2
Total liabilities | 3,231 | 3,121
Gross liability (recoverable) | 513 | 568
Ceded recoverable (liability) | 17 | 15
Fair Value [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Other investments | 3 |
Total assets | 3 |
Long-term debt | 272 | 330
Medium-term notes | 286 | 310
Investment agreements | 238 | 257
Variable interest entity loans payable | 3 | 2
Total liabilities | 799 | 899
Gross liability (recoverable) | 764 | 864
Ceded recoverable (liability) | 19 | 21
Fair Value [Member] | Fair Value Inputs Level 1 [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Other investments | 0 |
Total assets | 0 |
Long-term debt | 0 | 0
Medium-term notes | 0 | 0
Investment agreements | 0 | 0
Variable interest entity loans payable | 0 | 0
Total liabilities | 0 | 0
Gross liability (recoverable) | 0 | 0
Ceded recoverable (liability) | 0 | 0
Fair Value [Member] | Fair Value Inputs Level 2 [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Other investments | 0 |
Total assets | 0 |
Long-term debt | 272 | 330
Medium-term notes | 0 | 0
Investment agreements | 0 | 0
Variable interest entity loans payable | 0 | 0
Total liabilities | 272 | 330
Gross liability (recoverable) | 0 | 0
Ceded recoverable (liability) | 0 | 0
Fair Value [Member] | Fair Value Inputs Level 3 [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Other investments | 3 |
Total assets | 3 |
Long-term debt | 0 | 0
Medium-term notes | 286 | 310
Investment agreements | 238 | 257
Variable interest entity loans payable | 3 | 2
Total liabilities | 527 | 569
Gross liability (recoverable) | 764 | 864
Ceded recoverable (liability) | $ 19 | $ 21

X
- Definition Represents the Company's balance sheet carrying amount of the financial guarantee insurance contracts ceded to third party reinsurers. The balance sheet carrying amount comprises the prepaid reinsurance premiums and reinsurance recoverable on paid and unpaid losses + References No definition available. + Details
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- Definition Represents the Company's balance sheet carrying amount of the financial guarantee insurance contract obligations with third parties. The gross balance sheet carrying amount comprises the unearned premium revenue and the loss and loss adjustment expense reserves balances + References No definition available. + Details
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- Definition Guaranteed Investment Agreements Fair Value + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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- Definition Including the current and noncurrent portions, carrying value at the balance sheet date of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years. + 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://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: 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//1943274/2147479853/942-210-S99-1 + Details
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- Definition Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer. + 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://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: 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//1943274/2147479853/942-210-S99-1 + Details
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