Commitments, Contingencies and Guarantees (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Commitments, Contingencies and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 90
Escrow deposits and settlement withholdings	18	$ 8
Commitments to Extend Credit [Member]
Commitments, Contingencies and Guarantees [Line Items]
Unused commitments to extend credit for loans	$ 210,900

[Line Items] for Schedule of Commitments, Contingencies and Guarantees [Table]

No definition available.

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- Definition

Amounts withheld from merchants or covered by third-party guarantors, to mitigate the risk of potential loss relating to merchant chargeback guarantees.

+ References

No definition available.

+ Details

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

+ 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=118943654&loc=d3e12069-110248

+ Details

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- Details

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