Net Capital Requirements - Partnership's Capital Figures for U.S. and Canada Broker-Dealer Subsidiaries (Detail) - USD ($) $ in Millions	Jun. 27, 2025	Dec. 31, 2024
Subsidiaries [Member]
Regulatory Capital Requirements
Net capital	$ 1,088	$ 938
Net capital in excess of the minimum required	$ 1,018	$ 873
Net capital as a percentage of aggregate debit items	30.80%	28.90%
Net capital after anticipated capital withdrawals, as a percentage of aggregate debit items	4.20%	5.20%
Canada [Member]
Regulatory Capital Requirements
Regulatory risk-adjusted capital	$ 77	$ 71
Regulatory risk-adjusted capital in excess of the minimum required	$ 76	$ 69

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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