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Variable Interest Entities (Narrative) (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Dec. 31, 2012
Variable Interest Entity [Line Items] |  |  |  |  |
Carrying amounts of assets | $ 18,122 | $ 22,295 | $ 18,122 | $ 22,295 | $ 21,724
Carrying amounts of liabilities | 15,085 |  | 15,085 |  | 18,530
Number of variable interest entities consolidated | 0 | 0 | 0 | 0 |
Net realized gains (losses) related to deconsolidation | 1 | 0 | 1 | 0 |
Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Carrying amounts of assets | 6,800 |  | 6,800 |  | 8,300
Carrying amounts of liabilities | 5,700 |  | 5,700 |  | 7,300
Variable Interest Entity Non Primary Beneficiary [Member] | Financial Intermediary [Member] |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
VIE Assets | $ 135 |  | $ 135 |  |

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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The amount of the gain (loss) recognized by the parent and included in its attributable portion of net income for the period due to deconsolidation of a subsidiary or derecognition of a group of assets. The gain (loss) recognized and included in the net income attributable to the parent for the period is generally computed as the difference between: (a) the aggregate of: (1) the fair value of any consideration received; (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary was deconsolidated; and (3) the carrying amount of any noncontrolling interest in the former subsidiary (including any accumulated other comprehensive income attributable to the noncontrolling interest) at the date the subsidiary was deconsolidated and (b) the carrying amount of the former subsidiary's assets and liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4582445-111684 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 39 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 36 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future. + 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 210.5-02.19-26) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph a -URI http://asc.fasb.org/extlink&oid=7880789&loc=d3e5728-111685 + Details
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