Investments - Securities Lending and Repurchase Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Securities Lending Transactions:
Gross amount of securities on loan	$ 606	$ 820
Gross amount of associated liability for collateral received	621	840
Repurchase agreements:
Gross amount of recognized liabilities for repurchase agreements	0	72
Gross amount of collateral pledged related to repurchase agreements	0	73
Securities for Reverse Repurchase Agreements	15	64
Gross amount of associated liability for collateral received, securities	$ 34	$ 3

Securities Loaned, Collateral, Obligation to Return

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- Definition

Securities Loaned, Collateral, Obligation to Return Securities

+ References

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- Definition

Securities Sold Under Agreements to Repurchase, Collateral

+ 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(2)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- References

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- Definition

Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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- References

No definition available.

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- Definition

Amount, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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