Commitments, Contingencies and Guarantees - Guarantees (Detail) $ in Millions	Feb. 28, 2018 USD ($)
Derivative contracts—non-credit related
Guarantee Obligations [Line Items]
2018	$ 19,737.1
2019	3,134.8
2020 and 2021	1,429.2
2022 and 2023	215.0
2024 and Later	478.2
Notional/ Maximum Payout	24,994.3
Written derivative contracts—credit related
Guarantee Obligations [Line Items]
2018	0.0
2019	42.7
2020 and 2021	7.5
2022 and 2023	23.1
2024 and Later	0.0
Notional/ Maximum Payout	73.3
Derivatives
Guarantee Obligations [Line Items]
2018	19,737.1
2019	3,177.5
2020 and 2021	1,436.7
2022 and 2023	238.1
2024 and Later	478.2
Notional/ Maximum Payout	$ 25,067.6

Guarantees with a remaining term that matures during the fiscal year. These may include derivative guarantees, etc.

No definition available.

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- Definition

Guarantees expected to be due within 5 to 6 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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- Definition

Guarantees expected to be due within 3 to 4 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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- Definition

Guarantees expected to be due within 2 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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- Definition

Guarantees expected to be due within 7 fiscal years and thereafter. These may include, derivative guarantees, etc

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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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