Fair Value - Partnership's Financial Assets and Liabilities at Fair Value (Detail) - USD ($) $ in Millions | Sep. 27, 2024 | Dec. 31, 2023 |
Cash equivalents: | | | |
Total cash equivalents | | $ 236 | $ 255 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 9,038 | 11,393 |
Securities owned: | | | |
Total investment securities | | 1,379 | 1,069 |
Inventory securities: | | | |
Total inventory securities | | 214 | 88 |
Other Assets: | | | |
Client Fractional Shares Ownership Assets | | 925 | 824 |
Accounts payable, accrued expenses and other: | | | |
Client Fractional Shares Redemption Obligations | | 925 | 824 |
Equities [Member] | | | |
Securities owned: | | | |
Total investment securities | | 8 | 11 |
Inventory securities: | | | |
Total inventory securities | | 19 | 21 |
Corporate Bonds and Notes [Member] | | | |
Inventory securities: | | | |
Total inventory securities | | 15 | 5 |
Government and Agency Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 895 | 600 |
Inventory securities: | | | |
Total inventory securities | | 15 | 4 |
U.S. Treasuries [Member] | | | |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 7,938 | 9,893 |
Mutual Funds [Member] | | | |
Securities owned: | | | |
Total investment securities | [1] | 364 | 346 |
Inventory securities: | | | |
Total inventory securities | | 103 | 9 |
Municipal Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 12 | 12 |
Inventory securities: | | | |
Total inventory securities | | 50 | 29 |
Certificates of deposit [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 163 | 179 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 1,100 | 1,500 |
Securities owned: | | | |
Total investment securities | | 100 | 100 |
Inventory securities: | | | |
Total inventory securities | | 12 | 20 |
Money Market Funds [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 73 | 76 |
Level I [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 73 | 76 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 7,938 | 9,893 |
Securities owned: | | | |
Total investment securities | | 1,267 | 957 |
Inventory securities: | | | |
Total inventory securities | | 137 | 34 |
Other Assets: | | | |
Client Fractional Shares Ownership Assets | | 925 | 824 |
Accounts payable, accrued expenses and other: | | | |
Client Fractional Shares Redemption Obligations | | 925 | 824 |
Level I [Member] | Equities [Member] | | | |
Securities owned: | | | |
Total investment securities | | 8 | 11 |
Inventory securities: | | | |
Total inventory securities | | 19 | 21 |
Level I [Member] | Corporate Bonds and Notes [Member] | | | |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level I [Member] | Government and Agency Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 895 | 600 |
Inventory securities: | | | |
Total inventory securities | | 15 | 4 |
Level I [Member] | U.S. Treasuries [Member] | | | |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 7,938 | 9,893 |
Level I [Member] | Mutual Funds [Member] | | | |
Securities owned: | | | |
Total investment securities | [1] | 364 | 346 |
Inventory securities: | | | |
Total inventory securities | | 103 | 9 |
Level I [Member] | Municipal Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level I [Member] | Certificates of deposit [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 0 | 0 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 0 | 0 |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level I [Member] | Money Market Funds [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 73 | 76 |
Level II [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 163 | 179 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 1,100 | 1,500 |
Securities owned: | | | |
Total investment securities | | 112 | 112 |
Inventory securities: | | | |
Total inventory securities | | 77 | 54 |
Other Assets: | | | |
Client Fractional Shares Ownership Assets | | 0 | 0 |
Accounts payable, accrued expenses and other: | | | |
Client Fractional Shares Redemption Obligations | | 0 | 0 |
Level II [Member] | Equities [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level II [Member] | Corporate Bonds and Notes [Member] | | | |
Inventory securities: | | | |
Total inventory securities | | 15 | 5 |
Level II [Member] | Government and Agency Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level II [Member] | U.S. Treasuries [Member] | | | |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 0 | 0 |
Level II [Member] | Mutual Funds [Member] | | | |
Securities owned: | | | |
Total investment securities | [1] | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level II [Member] | Municipal Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 12 | 12 |
Inventory securities: | | | |
Total inventory securities | | 50 | 29 |
Level II [Member] | Certificates of deposit [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 163 | 179 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 1,100 | 1,500 |
Securities owned: | | | |
Total investment securities | | 100 | 100 |
Inventory securities: | | | |
Total inventory securities | | 12 | 20 |
Level II [Member] | Money Market Funds [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 0 | 0 |
Level III [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 0 | 0 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 0 | 0 |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Other Assets: | | | |
Client Fractional Shares Ownership Assets | | 0 | 0 |
Accounts payable, accrued expenses and other: | | | |
Client Fractional Shares Redemption Obligations | | 0 | 0 |
Level III [Member] | Equities [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | Corporate Bonds and Notes [Member] | | | |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | Government and Agency Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | U.S. Treasuries [Member] | | | |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 0 | 0 |
Level III [Member] | Mutual Funds [Member] | | | |
Securities owned: | | | |
Total investment securities | [1] | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | Municipal Obligations [Member] | | | |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | Certificates of deposit [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | 0 | 0 |
Investments segregated under federal regulations: | | | |
Total investments segregated under federal regulations | | 0 | 0 |
Securities owned: | | | |
Total investment securities | | 0 | 0 |
Inventory securities: | | | |
Total inventory securities | | 0 | 0 |
Level III [Member] | Money Market Funds [Member] | | | |
Cash equivalents: | | | |
Total cash equivalents | | $ 0 | $ 0 |
| |
[1] The mutual funds balance consists primarily of securities held to economically hedge future liabilities for the non-qualified deferred compensation plan. The balance also includes a security held for regulatory purposes at the Trust Co. | |