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Fair Value Measurements - Unobservable Data Used in Recurring Valuations of Level 3 (Detail) $ in Millions | Jun. 30, 2019 USD ($) | Dec. 31, 2018 USD ($)
--- | --- | ---
Interest Rate Swaps [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | $ 219 | $ 94
Cross-Currency Interest Rate Swaps [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | (603) | (659)
Other [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | (2) | $ (4)
Level 3 [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | (626) |
Level 3 [Member] | Cross-Currency Interest Rate Swaps [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | $ (603) |
Derivative Asset (Liability) Net, Valuation Technique [Extensible List] | us-gaap:ValuationTechniqueDiscountedCashFlowMember |
Derivatives | 0.04 |
Derivative Asset (Liability) Net, Measurement Input [Extensible List] | us-gaap:MeasurementInputConstantPrepaymentRateMember |
Level 3 [Member] | Other [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | $ (2) |
Level 3 [Member] | Prime/LIBOR Basis Swaps [Member] | Interest Rate Swaps [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivative financial instruments, Fair Value | $ (21) |
Derivative Asset (Liability) Net, Valuation Technique [Extensible List] | us-gaap:ValuationTechniqueDiscountedCashFlowMember |
Level 3 [Member] | Prime/LIBOR Basis Swaps [Member] | Interest Rate Swaps [Member] | Constant Prepayment Rate [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivatives | 0.07 |
Level 3 [Member] | Prime/LIBOR Basis Swaps [Member] | Interest Rate Swaps [Member] | Bid/ask adjustment to discount rate [Member] | Minimum [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivatives | 0.0008 |
Level 3 [Member] | Prime/LIBOR Basis Swaps [Member] | Interest Rate Swaps [Member] | Bid/ask adjustment to discount rate [Member] | Maximum [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivatives | 0.0008 |
Level 3 [Member] | Prime/LIBOR Basis Swaps [Member] | Interest Rate Swaps [Member] | Bid/ask adjustment to discount rate [Member] | Weighted Average [Member] |  |
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Derivatives | (0.0008) |

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