The amount of cash received as security in return for loaning securities to another party.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(11))
-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value of the securities pledged as collateral against securities loaned.

+ References

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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Namespace Prefix:
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- Details

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Investments (Securities Lending Programs) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Loaned, Fair Value of Collateral	$ 1,841	$ 1,199
Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral received for securities loaned, at carrying value	1,841
Overnight and Continuous [Member] \| Cash [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral received for securities loaned, at carrying value	1,739
Overnight and Continuous [Member] \| United States Government Securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral received for securities loaned, at carrying value	$ 102