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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 | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Variable Interest Entity Primary Beneficiary [Member] |  |
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items] |  |
Investments held-to-maturity, fair value | $ 967 | $ 925
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] |  |
Other investments | 1 | 1
Total assets | 891 | 891
Long-term debt | 2,315 | 2,249
Medium-term notes | 569 | 620
Investment agreements | 305 | 311
Total liabilities | 4,409 | 4,444
Gross | (105) | (43)
Ceded | 30 | 35
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 | 890 | 890
Variable interest entity notes | 1,220 | 1,264
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] |  |
Other investments | 1 | 1
Total assets | 968 | 926
Long-term debt | 1,219 | 1,101
Medium-term notes | 393 | 422
Investment agreements | 398 | 388
Total liabilities | 3,313 | 3,214
Gross | 1,317 | 993
Ceded | 79 | 65
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 | 967 | 925
Variable interest entity notes | 1,303 | 1,303
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] |  |
Other investments |  | 1
Total assets |  | 1
Long-term debt | 1,219 | 1,101
Total liabilities | 1,555 | 1,479
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] |  |
Variable interest entity notes | 336 | 378
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] |  |
Other investments | 1 |
Total assets | 968 | 925
Medium-term notes | 393 | 422
Investment agreements | 398 | 388
Total liabilities | 1,758 | 1,735
Gross | 1,317 | 993
Ceded | 79 | 65
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 | 967 | 925
Variable interest entity notes | $ 967 | $ 925

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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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