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Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions | Jun. 30, 2019 | Dec. 31, 2018
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Derivative Instruments, Gain (Loss) [Line Items] |  |
Decrease in valuation due to net credit risk adjustments | $ 15 | $ 26
Decrease in valuation due to liquidity adjustments | 15 | 19
Derivative liability at fair value including accrued interest and premium receivable | 713 | $ 752
Counterparty [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability at fair value including accrued interest and premium receivable | $ 73 |

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- Definition Decrease in valuation due to liquidity adjustments. + References No definition available. + Details
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- Definition Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties. + References No definition available. + 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 The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959 + Details
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