Commitments, Contingencies and Guarantees - Commitments and Contingencies (Detail) (USD $) In Millions, unless otherwise specified	Feb. 28, 2015
Commitments And Guarantee Obligations [Line Items]
2015	$ 3,232.6
2016	1,746.5
2017 and 2018	315.9
2019 and 2020	48.3
2021 and Later	193.7
Maximum Payout	5,537.0
Equity commitments [Member]
Commitments And Guarantee Obligations [Line Items]
2015	0
2016	9.2
2017 and 2018	0.8
2019 and 2020	0
2021 and Later	171.8
Maximum Payout	181.8
Loan commitments [Member]
Commitments And Guarantee Obligations [Line Items]
2015	44.6
2016	421.7
2017 and 2018	188.9
2019 and 2020	48.3
2021 and Later	0
Maximum Payout	703.5
Mortgage-related commitments [Member]
Commitments And Guarantee Obligations [Line Items]
2015	1,123.1
2016	1,315.6
2017 and 2018	126.2
2019 and 2020	0
2021 and Later	0
Maximum Payout	2,564.9
Forward starting reverse repos and repos [Member]
Commitments And Guarantee Obligations [Line Items]
2015	2,034.9
2016	0
2017 and 2018	0
2019 and 2020	0
2021 and Later	0
Maximum Payout	2,034.9
Other unfunded commitments [Member]
Commitments And Guarantee Obligations [Line Items]
2015	30.0
2016	0
2017 and 2018	0
2019 and 2020	0
2021 and Later	21.9
Maximum Payout	$ 51.9

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Commitments and guarantees with a remaining term that matures during the fiscal year. These may include, equity, loan, mortgage-related and underwriting commitments, derivative guarantees, etc.

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Commitments and guarantees expected to be due within 5 to 6 fiscal years. These may include, equity, loan, mortgage-related and underwriting commitments, derivative guarantees, etc.

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No definition available.

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Commitments and guarantees expected to be due within 3 to 4 fiscal years. These may include, equity, loan, mortgage-related and underwriting commitments, derivative guarantees, etc.

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No definition available.

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Commitments and guarantees expected to be due within 2 fiscal years. These may include, equity, loan, mortgage-related and underwriting commitments, derivative guarantees, etc.

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No definition available.

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Commitments and guarantees expected to be due within 7 fiscal years and thereafter. These may include, equity, loan, mortgage-related and underwriting commitments and derivative guarantees, etc.

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No definition available.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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