Net Capital Requirements - Partnership's Capital Figures for U.S. and Canada Broker-Dealer Subsidiaries (Detail) - USD ($) $ in Millions	Sep. 27, 2019	Dec. 31, 2018
United States [Member]
Regulatory Capital Requirements
Net capital	$ 1,311	$ 1,280
Net capital in excess of the minimum required	$ 1,254	$ 1,221
Net capital as a percentage of aggregate debit items	46.00%	43.60%
Net capital after anticipated capital withdrawals, as a percentage of aggregate debit items	30.00%	28.30%
Canada [Member]
Regulatory Capital Requirements
Regulatory risk-adjusted capital	$ 40	$ 40
Regulatory risk-adjusted capital in excess of the minimum required to be held by IIROC	$ 39	$ 39

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
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Amount of net capital of broker-dealer.

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

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