Level 4 - Securities Lending and Repurchase Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Securities Lending Transactions:
Gross amount of securities on loan	$ 297	$ 277
Gross amount of associated liability for collateral received	304	284
Repurchase agreements:
Gross amount of recognized liabilities for repurchase agreements	195	186
Gross amount of collateral pledged related to repurchase agreements	197	190
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	35	25
Gross amount of associated liability for collateral received, securities	5	1
Interest-bearing Deposit Liabilities, Domestic	$ 23	$ 23

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, Obligation to Return

+ References

No definition available.

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- Definition

Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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

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- Definition

Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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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