Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Gross amounts recognized	$ 457,317	$ 602,754
Derivative liabilities - Fair value	344,135	424,828
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	22,005,910	21,341,158
Gross amounts recognized	456,409	602,754
Derivative liabilities - Fair value	342,877	422,729
Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	4,036,958	3,108,488
Gross amounts recognized	38,654	30,300
Derivative liabilities - Fair value	27,287	22,524
Foreign exchange contracts \| Customer Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,468,974	1,522,888
Gross amounts recognized	27,803	17,575
Derivative liabilities - Fair value	21,835	17,928
Foreign exchange contracts \| Customer Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	184,584	13,590
Gross amounts recognized	1,902	872
Derivative liabilities - Fair value	247	91
Foreign exchange contracts \| Customer Counterparty \| Written options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	116,575	117,729
Gross amounts recognized	0	0
Derivative liabilities - Fair value	336	574
Foreign exchange contracts \| Customer Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	3,167
Gross amounts recognized	0
Derivative liabilities - Fair value	11
Foreign exchange contracts \| Customer Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,773,300	1,654,207
Gross amounts recognized	29,705	18,447
Derivative liabilities - Fair value	22,429	18,593
Foreign exchange contracts \| Financial Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	168,942	145,197
Gross amounts recognized	869	1,230
Derivative liabilities - Fair value	494	273
Foreign exchange contracts \| Financial Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	974,974	1,191,355
Gross amounts recognized	7,733	10,049
Derivative liabilities - Fair value	4,364	3,658
Foreign exchange contracts \| Financial Counterparty \| Purchased options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	116,575	117,729
Gross amounts recognized	336	574
Derivative liabilities - Fair value	0	0
Foreign exchange contracts \| Financial Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	3,167
Gross amounts recognized	11
Derivative liabilities - Fair value	0
Foreign exchange contracts \| Financial Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	1,263,658	1,454,281
Gross amounts recognized	8,949	11,853
Derivative liabilities - Fair value	$ 4,858	$ 3,931

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

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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.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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