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Debt (Principal Payments For Investment Agreements, MTNs and VIE Obligations) (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Debt Instrument [Line Items] |  |  |
2022 |  | $ 265 |
Thereafter |  | 1,248 |
Total |  | 1,513 |
Accrued interest |  | 624 | $ 506
Investment Agreement Obligations [Member] |  |  |
Debt Instrument [Line Items] |  |  |
2018 |  | 17 |
2019 |  | 7 |
2020 |  | 35 |
2021 |  | 3 |
2022 |  | 3 |
Thereafter |  | 328 |
Total expected principal payments | [1] | 393 |
Less discount and other adjustments | [2] | 56 |
Total |  | 337 |
Less unamortized discount |  | 61 |
Accrued interest |  | $ 5 |
Latest maturity year |  | 2037 |
Medium Term Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
2018 |  | $ 36 |
2019 |  | 61 |
2020 |  | 0 |
2021 |  | 0 |
2022 |  | 121 |
Thereafter |  | 847 |
Total expected principal payments | [3] | 1,065 |
Less discount and other adjustments | [4] | 300 |
Total |  | 765 |
Less unamortized discount |  | 240 |
Accrued interest |  | 5 |
Fair value adjustments |  | $ 65 |
Latest maturity year |  | 2036 |
Variable Interest Entity Debt [Member] | International And Structured Finance Insurance [Member] |  |  |
Debt Instrument [Line Items] |  |  |
2018 |  | $ 203 |
2019 |  | 147 |
2020 |  | 485 |
2021 |  | 132 |
2022 |  | 116 |
Thereafter |  | 1,206 |
Total expected principal payments | [5] | 2,289 |
Net fair value |  | $ 1,100 |
Latest maturity year |  | 2052 |
[1] | Amounts reflect principal due at maturity for investment agreements issued at a discount.
[2] | Includes discounts net of carrying amount adjustments of $66 million, net of accrued interest of $5 million.
[3] | Amounts reflect principal due at maturity for notes issued at a discount.
[4] | Includes discounts net of carrying amount adjustments and embedded derivatives of $279 million, fair value adjustments of $57 million, net of accrued interest of $3 million.
[5] | Includes $1.1 billion of VIE notes accounted for at fair value as of December 31, 2016.

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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