v3.20.4
Revenue - Schedule of Estimated Technology Services Revenue Expected to Be Recognized in Future, Related to Unsatisfied Portion of Performance Obligations (Detail) - Technology Services Revenue [Member] - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation $ 231 $ 221
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-01-01    
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period   1 year
Revenue, Remaining Performance Obligation   $ 117
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-01-01    
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year 1 year
Revenue, Remaining Performance Obligation $ 118 $ 53
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01    
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year 1 year
Revenue, Remaining Performance Obligation $ 58 $ 31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01    
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation $ 33 $ 20
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2024-01-01    
Schedule of Investment Advisory Administration Fees and Securities Lending Revenue and Performance Fees by Type [line Items]    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period  
Revenue, Remaining Performance Obligation $ 22