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Commitments, Contingencies, Guarantees, and Others - Litigation (Details) $ in Millions |  | 1 Months Ended
--- | --- | ---
Dec. 31, 2019 USD ($) claim | Oct. 31, 2018 USD ($)
Loss Contingencies [Line Items] |  |
Loss contingency, estimate of possible loss | $ | $ 1,100 |
Number of consumer class action cases filed for Cybersecurity Incident | claim | 72 |
Anti-money laundering |  |
Loss Contingencies [Line Items] |  |
Litigation settlement paid | $ |  | $ 100
Pending litigation | Interchange litigation |  |
Loss Contingencies [Line Items] |  |
Litigation settlement, attributable to reporting entity and third party | $ | $ 5,500 |
United States |  |
Loss Contingencies [Line Items] |  |
Number of consumer class action cases filed for Cybersecurity Incident | claim | 61 |
Canada |  |
Loss Contingencies [Line Items] |  |
Number of consumer class action cases filed for Cybersecurity Incident | claim | 11 |

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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12021-110248 + Details
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