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Variable Interest Entities (Narrative) (Detail) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 USD ($) | Sep. 30, 2014 | Dec. 31, 2014 USD ($)
Variable Interest Entity [Line Items] |  |  |
Carrying amounts of assets | $ 5,500 |  | $ 5,000
Carrying amounts of liabilities | $ 5,200 |  | 4,800
Number of variable interest entities consolidated | 1 | 1 |
Number of variable interest entities deconsolidated | 1 |  |
Advisory Services [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying amounts of assets |  |  | 751
Carrying amounts of liabilities |  |  | $ 754
Variable Interest Entity Primary Beneficiary [Member] | Advisory Services [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Number of variable interest entities consolidated |  |  | 3
Variable Interest Entity Primary Beneficiary [Member] | Collateral Loan Obligations [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Investments carried at fair value |  |  | $ 4

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- Definition Represents the number of VIEs consolidated during the period. + References No definition available. + Details
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- Definition Represents the number of VIEs deconsolidated during the period. + References No definition available. + Details
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- Definition Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 + Details
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- Definition The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685 + Details
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- Definition The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685 + Details
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