Commitments, Contingencies and Guarantees - Summary of Notional Amounts Associated with Derivative Contracts (Details) $ in Millions	Dec. 31, 2017 USD ($)
Derivative contracts – non-credit related
Guarantor Obligations [Line Items]
2018	$ 24,454.8
2019	2,420.2
2020 and 2021	150.5
2022 and 2023	45.9
2024 and Later	466.3
Maximum Payout	27,537.7
Written derivative contracts – credit related
Guarantor Obligations [Line Items]
2018	0.0
2019	42.0
2020 and 2021	20.5
2022 and 2023	155.7
2024 and Later	0.0
Maximum Payout	218.2
Derivatives
Guarantor Obligations [Line Items]
2018	24,454.8
2019	2,462.2
2020 and 2021	171.0
2022 and 2023	201.6
2024 and Later	466.3
Maximum Payout	$ 27,755.9

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.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Guarantees Expected To Be Due, Next Twelve Months

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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

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No definition available.

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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.

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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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