Offsetting Assets and Liabilities - Schedule of Partnership's Securities Purchased Under Agreement to Resell (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Offsetting Securities Purchased Under Agreements To Resell [Abstract]
Securities purchased under agreements to resell, Gross amounts of recognized assets	$ 770	$ 843
Securities purchased under agreements to resell, Gross amounts offset in the Consolidated Statements of Financial Condition	0	0
Securities purchased under agreements to resell, Net amounts presented in the Consolidated Statements of Financial Condition	770	843
Securities purchased under agreements to resell, gross amounts not offset, financial instruments	0	0
Securities purchased under agreements to resell, gross amounts not offset, securities collateral	(770)	(843)
Securities purchased under agreements to resell, Net amount	$ 0	$ 0

Securities purchased under agreements to resell gross amounts offset.

No definition available.

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- Definition

Amount of obligation to return financial instruments collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(2)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount, after effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313

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- Definition

Amount of obligation to return securities collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313

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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Name Accounting Standards Codification
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