Net Capital Requirements - Partnership's Capital Figures for U.S. and Canada Broker-Dealer Subsidiaries (Detail) - USD ($) $ in Millions	Sep. 27, 2024	Dec. 31, 2023
Subsidiaries [Member]
Regulatory Capital Requirements
Net capital	$ 1,383	$ 981
Net capital in excess of the minimum required	$ 1,320	$ 919
Net capital as a percentage of aggregate debit items	43.60%	31.70%
Net capital after anticipated capital withdrawals, as a percentage of aggregate debit items	12.90%	13.00%
Canada [Member]
Regulatory Capital Requirements
Regulatory risk-adjusted capital	$ 101	$ 136
Regulatory risk-adjusted capital in excess of the minimum required	$ 94	$ 134

Capital in excess required to be held by investment industry regulatory organization of foreign country.

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Foreign country brokers dealers regulatory risk adjusted capital.

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Net capital after anticipated capital withdrawals to aggregate debit items percentage.

No definition available.

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Net capital to aggregate debit item percentage.

No definition available.

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Amount of net capital in excess of minimum required net capital, calculated under Alternative Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Amount of net capital of broker-dealer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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