Derivative Financial Instruments - Collateral Held and Pledged (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Collateral held:
Cash (obligation to return cash collateral is recorded in short-term borrowings)	$ 359	$ 266
Securities at fair value - on-balance sheet securitization derivatives (not recorded in financial statements)	79	90
Total collateral held	438	356
Derivative asset at fair value including accrued interest	307	210
Collateral pledged to others:
Cash (right to receive return of cash collateral is recorded in investments)	164	188
Total collateral pledged	164	188
Derivative liability at fair value including accrued interest and premium receivable	$ 713	$ 752

Collateral held.

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- Definition

Collateral pledged to others.

+ References

No definition available.

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- Definition

Derivative asset at fair value including accrued interest.

+ References

No definition available.

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- Definition

Securities fair value on balance sheet securitization derivatives.

+ References

No definition available.

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- Definition

Fair value of securities received as collateral against derivative assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

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-Publisher FASB
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-Topic 210
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-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

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- Definition

Fair value of securities pledged as collateral against derivative liabilities.

+ References

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
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