Derivative Instruments and Hedging Activities - Protection Purchased with CDS (Details) - Protection Purchased - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
CDS
Credit Derivatives
Fair Value Asset (Liability)	$ (1,175)	$ 1,359
Notional	255,000	247,000
Single name
Credit Derivatives
Fair Value Asset (Liability)	147	277
Notional	119,000	116,000
Index and basket
Credit Derivatives
Fair Value Asset (Liability)	(977)	1,333
Notional	120,000	117,000
Tranched index and basket
Credit Derivatives
Fair Value Asset (Liability)	(345)	(251)
Notional	$ 16,000	$ 14,000

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No definition available.

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- Definition

Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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