Commitments, Contingencies and Guarantees (Guarantees) (Details) - Derivative Notional Amount $ in Millions	Feb. 28, 2019 USD ($)
Derivative contracts – non-credit related
Guarantee Obligations [Line Items]
2019	$ 9,764.7
2020	2,569.7
2021 and 2022	4,148.7
2023 and 2024	281.8
2025 and Later	332.3
Notional/ Maximum Payout	17,097.2
Written derivative contracts – credit related
Guarantee Obligations [Line Items]
2019	0.0
2020	32.4
2021 and 2022	1.5
2023 and 2024	61.0
2025 and Later	0.0
Notional/ Maximum Payout	94.9
Derivatives
Guarantee Obligations [Line Items]
2019	9,764.7
2020	2,602.1
2021 and 2022	4,150.2
2023 and 2024	342.8
2025 and Later	332.3
Notional/ Maximum Payout	$ 17,192.1

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

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- Definition

Guarantees expected to be due within 2 year. 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 with a remaining term that matures during the fiscal year. These may include derivative guarantees, etc.

+ References

No definition available.

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- Definition

Guarantees expected to be due within 6 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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