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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) - USD ($) $ in Millions | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Variable Interest Entity Primary Beneficiary [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | $ 575 | $ 892
Variable interest entity notes | 1,187 | 1,539
Carrying Reported Amount Fair Value Disclosure [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Total assets | 575 | 890
Long-term debt | 2,318 | 2,228
Medium-term notes | 583 | 570
Investment agreements | 293 | 304
Total liabilities | 4,038 | 4,238
Gross | (378) | (311)
Ceded recoverable (liability) | (18) | 24
Carrying Reported Amount Fair Value Disclosure [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Variable Interest Entity Primary Beneficiary [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | 575 | 890
Variable interest entity notes | 844 | 1,136
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Total assets | 575 | 892
Long-term debt | 724 | 1,073
Medium-term notes | 379 | 396
Investment agreements | 408 | 394
Total liabilities | 2,350 | 3,016
Gross | 595 | 556
Ceded recoverable (liability) | 41 | 56
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Variable Interest Entity Primary Beneficiary [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | 575 | 892
Variable interest entity notes | 839 | 1,153
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 1 [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Total assets | 0 | 0
Long-term debt | 0 | 0
Medium-term notes | 0 | 0
Investment agreements | 0 | 0
Total liabilities | 0 | 0
Gross | 0 | 0
Ceded recoverable (liability) | 0 | 0
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 1 [Member] | Variable Interest Entity Primary Beneficiary [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | 0 | 0
Variable interest entity notes | 0 | 0
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 2 [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Total assets | 0 | 0
Long-term debt | 724 | 1,073
Medium-term notes | 0 | 0
Investment agreements | 0 | 0
Total liabilities | 988 | 1,334
Gross | 0 | 0
Ceded recoverable (liability) | 0 | 0
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 2 [Member] | Variable Interest Entity Primary Beneficiary [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | 0 | 0
Variable interest entity notes | 264 | 261
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 3 [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Total assets | 575 | 892
Long-term debt | 0 | 0
Medium-term notes | 379 | 396
Investment agreements | 408 | 394
Total liabilities | 1,362 | 1,682
Gross | 595 | 556
Ceded recoverable (liability) | 41 | 56
Fair Value [Member] | Value Disclosed At Fair Value Not Recorded At Fair Value [Member] | Fair Value Inputs Level 3 [Member] | Variable Interest Entity Primary Beneficiary [Member] | Fair Value Measurements Nonrecurring [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | 575 | 892
Variable interest entity notes | $ 575 | $ 892

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- 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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