v3.8.0.1

Investments (Repurchase Agreements and Securities Lending Transactions) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | $ 8,400 | $ 7,606
Total cash collateral for loaned securities | 4,354 | 4,333
Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 912 | 956
Total cash collateral for loaned securities | 4,319 | 4,259
Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 7,488 | 6,650
Total cash collateral for loaned securities | 35 | 74
U.S. Treasury securities and obligations of U.S. government authorities and agencies |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 8,260 | 7,367
Total cash collateral for loaned securities | 122 | 9
U.S. Treasury securities and obligations of U.S. government authorities and agencies | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 911 | 950
Total cash collateral for loaned securities | 87 | 9
U.S. Treasury securities and obligations of U.S. government authorities and agencies | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 7,349 | 6,417
Total cash collateral for loaned securities | 35 | 0
Obligations of U.S. states and their political subdivisions |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 103 | 18
Obligations of U.S. states and their political subdivisions | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 103 | 18
Obligations of U.S. states and their political subdivisions | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 0 | 0
Foreign government bonds |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 335 | 279
Foreign government bonds | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 335 | 279
Foreign government bonds | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total cash collateral for loaned securities | 0 | 0
U.S. corporate public securities |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 1 | 0
Total cash collateral for loaned securities | 2,961 | 2,731
U.S. corporate public securities | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 1 | 0
Total cash collateral for loaned securities | 2,961 | 2,731
U.S. corporate public securities | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | 0 | 0
Foreign corporate public securities |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 6
Total cash collateral for loaned securities | 655 | 786
Foreign corporate public securities | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 6
Total cash collateral for loaned securities | 655 | 786
Foreign corporate public securities | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | 0 | 0
Residential mortgage-backed securities |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 139 | 233
Total cash collateral for loaned securities | 0 | 129
Residential mortgage-backed securities | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | 0 | 55
Residential mortgage-backed securities | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 139 | 233
Total cash collateral for loaned securities | 0 | 74
Equity securities |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | 178 | 381
Equity securities | Overnight & Continuous |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | 178 | 381
Equity securities | Up to 30 Days |  |
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] |  |
Total securities sold under agreements to repurchase | 0 | 0
Total cash collateral for loaned securities | $ 0 | $ 0

X
- Definition Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial asset at a date certain for a specified price. Includes repurchase-to-maturity transactions and liabilities not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 7 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL34722452-111729 + Details
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- Definition Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and financial assets transferred other than securities that qualify as secured borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 7 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL34722452-111729 + Details
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