Fair Value Measurements - Schedule of Cumulative Basis Adjustments for Fair Value Hedges (Details) - Long-term debt - Fair Value Hedges - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Carrying amount of hedged liabilities	$ 19,341	$ 18,903
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged liabilities	$ 373
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged assets		$ (785)

Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

No definition available.

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- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ References

No definition available.

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- Definition

Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

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