Derivative Instruments and Hedging Activities - Protection Purchased with CDS (Details) - Protection Purchased - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Credit Derivatives
Notional	$ 349,000	$ 246,000
CDS
Credit Derivatives
Fair Value Asset (Liability)	(3,008)	(1,838)
Single name
Credit Derivatives
Notional	126,000	116,000
Fair Value Asset (Liability)	(1,460)	(1,452)
Index and basket
Credit Derivatives
Notional	208,000	116,000
Fair Value Asset (Liability)	(1,187)	(57)
Tranched index and basket
Credit Derivatives
Notional	15,000	14,000
Fair Value Asset (Liability)	$ (361)	$ (329)

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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
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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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