Investments - Summary of Carrying Value of Total Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Investment [Line Items]
Available-for-sale investments	$ 44	$ 201
Held-to-maturity investments	108	79
Total trading investments	785	536
Total Other Investments, Carrying Value	641	1,105
Total investments	1,578	1,921
Consolidated Sponsored Investment Funds [Member]
Investment [Line Items]
Total trading investments	700	443
Consolidated Sponsored Investment Funds [Member] \| Consolidated Voting Rights Entities [Member]
Investment [Line Items]
Total Other Investments, Carrying Value		270
Other Equity and Debt Securities [Member]
Investment [Line Items]
Total trading investments	20	29
Deferred Compensation Plan Fund [Member]
Investment [Line Items]
Total trading investments	65	64
Total Other Investments, Carrying Value	14	21
Carried Interest [Member] \| Consolidated Voting Rights Entities [Member]
Investment [Line Items]
Total Other Investments, Carrying Value	19	85
Equity Method Investments [Member]
Investment [Line Items]
Total Other Investments, Carrying Value	513	633
Cost Method Investments [Member]
Investment [Line Items]
Total Other Investments, Carrying Value	$ 95	$ 96

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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