v3.26.1
Receivables and Revenue - Schedule of Partnership's Disaggregated Revenue (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 27, 2026
Mar. 28, 2025
Disaggregation Of Revenue [Line Items]    
Total revenue from customers $ 4,519 $ 3,923
Net interest and dividends and other revenue 158 244
Net revenue 4,677 4,167
United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 4,404 3,828
Net interest and dividends and other revenue 144 219
Net revenue 4,548 4,047
Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 115 95
Net interest and dividends and other revenue 14 25
Net revenue 129 120
Total Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 4,069 3,480
Total Fee Revenue [Member] | United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3,970 3,402
Total Fee Revenue [Member] | Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 99 78
Asset-based Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3,882 3,294
Asset-based Fee Revenue [Member] | Advisory Programs Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3,089 2,545
Asset-based Fee Revenue [Member] | Service Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 441 410
Asset-based Fee Revenue [Member] | Cash Solutions Fees Member    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 135 145
Asset-based Fee Revenue [Member] | Other Asset-based Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 217 194
Asset-based Fee Revenue [Member] | United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3,786 3,219
Asset-based Fee Revenue [Member] | United States [Member] | Advisory Programs Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3,021 2,496
Asset-based Fee Revenue [Member] | United States [Member] | Service Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 413 384
Asset-based Fee Revenue [Member] | United States [Member] | Cash Solutions Fees Member    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 135 145
Asset-based Fee Revenue [Member] | United States [Member] | Other Asset-based Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 217 194
Asset-based Fee Revenue [Member] | Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 96 75
Asset-based Fee Revenue [Member] | Canada [Member] | Advisory Programs Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 68 49
Asset-based Fee Revenue [Member] | Canada [Member] | Service Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 28 26
Asset-based Fee Revenue [Member] | Canada [Member] | Cash Solutions Fees Member    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 0 0
Asset-based Fee Revenue [Member] | Canada [Member] | Other Asset-based Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 0 0
Account and Activity Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 187 186
Account and Activity Fee Revenue [Member] | Shareholder Accounting Services Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 114 118
Account and Activity Fee Revenue [Member] | Other Account and Activity Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 73 68
Account and Activity Fee Revenue [Member] | United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 184 183
Account and Activity Fee Revenue [Member] | United States [Member] | Shareholder Accounting Services Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 114 118
Account and Activity Fee Revenue [Member] | United States [Member] | Other Account and Activity Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 70 65
Account and Activity Fee Revenue [Member] | Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3 3
Account and Activity Fee Revenue [Member] | Canada [Member] | Shareholder Accounting Services Fees [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 0 0
Account and Activity Fee Revenue [Member] | Canada [Member] | Other Account and Activity Fee Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 3 3
Trade Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 450 443
Trade Revenue [Member] | Commissions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 395 384
Trade Revenue [Member] | Principal Transactions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 55 59
Trade Revenue [Member] | United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 434 426
Trade Revenue [Member] | United States [Member] | Commissions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 381 370
Trade Revenue [Member] | United States [Member] | Principal Transactions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 53 56
Trade Revenue [Member] | Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 16 17
Trade Revenue [Member] | Canada [Member] | Commissions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers 14 14
Trade Revenue [Member] | Canada [Member] | Principal Transactions [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from customers $ 2 $ 3