Derivative Instruments Level 4 Derivative Collateral Arrangements (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Security Owned and Pledged as Collateral, Fair Value	$ 48	$ 10
Margin Deposit Assets	215	165
Derivative Asset, Collateral, Obligation to Return Cash, Offset	65	188
Securities Received as Collateral	0	9
Collateral Pledged [Member]
Derivative [Line Items]
Security Owned and Pledged as Collateral, Fair Value	$ 526	$ 214

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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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.

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No definition available.

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The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

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- Definition

The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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