Investments - Summary of Cost and Carrying Value of Other Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Total Other Investments, Cost	$ 538	$ 903
Total Other Investments, Carrying Value	641	1,105
Consolidated Sponsored Investment Funds [Member] \| Consolidated Voting Rights Entities [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost		268
Total Other Investments, Carrying Value		270
Deferred Compensation Plan Fund [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	14	21
Total Other Investments, Carrying Value	14	21
Federal Reserve Bank Stock [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	93	92
Total Other Investments, Carrying Value	93	92
Other [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	2	4
Total Other Investments, Carrying Value	2	4
Carried Interest [Member] \| Consolidated Voting Rights Entities [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	0	0
Total Other Investments, Carrying Value	19	85
Equity Method Investments [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	429	518
Total Other Investments, Carrying Value	513	633
Cost Method Investments [Member]
Schedule of Investments [Line Items]
Total Other Investments, Cost	95	96
Total Other Investments, Carrying Value	$ 95	$ 96