Derivative Instruments Level 4 Derivative Collateral Arrangements (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Fair Value of Securities Received as Collateral that Can be Resold or Repledged	$ 207	$ 100
Derivative Asset, Collateral, Obligation to Return Cash, Offset	353	341
Security Owned and Pledged as Collateral, Fair Value	34	173
Securities Received as Collateral	$ 57
Information about Sources and Uses of Collateral that is Received Through Resale Agreements and Securities Borrowing Agreements	As of September 30, 2016, and December 31, 2015, the Company had no repledged securities and did not sell any securities. In addition, as of September 30, 2016, and December 31, 2015, non-cash collateral accepted was held in separate custodial accounts and was not included in the Company’s Condensed Consolidated Balance Sheets.
Collateral Pledged [Member]
Derivative [Line Items]
Security Owned and Pledged as Collateral, Fair Value	$ 934	873
Liability [Member]
Derivative [Line Items]
Securities Received as Collateral	$ 219	$ 100

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 05
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=51812966&loc=d3e93645-111703

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6467456&loc=d3e113888-111728

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