Related Party Transactions - Revenue for Services Provided to Related Parties (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Revenues from related parties	$ 8,522	$ 8,412	$ 7,903
Investment Advisory, Administration Fees and Securities Lending Revenue [Member]
Related Party Transaction [Line Items]
Revenues from related parties	8,323	8,226	7,692
Investment Advisory Performance Fees [Member]
Related Party Transaction [Line Items]
Revenues from related parties	131	112	143
Technology Services Revenue [Member]
Related Party Transaction [Line Items]
Revenues from related parties	9	9	9
Advisory and Other Revenue [Member]
Related Party Transaction [Line Items]
Revenues from related parties	$ 59	$ 65	$ 59

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Name:	us-gaap_RevenueFromRelatedParties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration