Securities Financing Activities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	$ 0	$ 0
Securities borrowed	0	0
Total	0	0
Repurchase agreements	0	0
Total	0	0
Collateral
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	0	0
Securities borrowed	(500)	(500)
Total	(500)	(500)
Repurchase agreements	(218)	(214)
Total	(218)	(214)
Federal Agency CMOs
Securities Financing Transaction [Line Items]
Assets pledged as collateral	283
Liabilities pledged as collateral	218
Gross Amount Presented in Balance Sheet
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	11	6
Securities borrowed	500	500
Total	511	506
Repurchase agreements	229	220
Total	229	220
Netting Adjustments
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	(11)	(6)
Securities borrowed	0	0
Total	(11)	(6)
Repurchase agreements	(11)	(6)
Total	$ (11)	$ (6)

Offsetting of financial assets.

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- Definition

Offsetting of financial liabilities.

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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-Name Accounting Standards Codification
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- Definition

Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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

+ References

No definition available.

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- Definition

The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

+ References

No definition available.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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Fair value of liabilities arising from or related to a financial instrument held by the entity for its own account (proprietary securities) which has been pledged to counterparties.

+ References

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