Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Gross amounts recognized	$ 588,582	$ 602,754
Derivative liabilities - Fair value	448,921	424,828
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	21,676,672	21,341,158
Gross amounts recognized	588,582	602,754
Derivative liabilities - Fair value	447,542	422,729
Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	3,756,284	3,108,488
Gross amounts recognized	29,867	30,300
Derivative liabilities - Fair value	20,360	22,524
Foreign exchange contracts \| Customer Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,299,644	1,522,888
Gross amounts recognized	20,026	17,575
Derivative liabilities - Fair value	16,189	17,928
Foreign exchange contracts \| Customer Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	103,086	13,590
Gross amounts recognized	182	872
Derivative liabilities - Fair value	651	91
Foreign exchange contracts \| Customer Counterparty \| Written options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	118,350	117,729
Gross amounts recognized	0	0
Derivative liabilities - Fair value	31	574
Foreign exchange contracts \| Customer Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,135
Gross amounts recognized	1
Derivative liabilities - Fair value	0
Foreign exchange contracts \| Customer Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,523,215	1,654,207
Gross amounts recognized	20,209	18,447
Derivative liabilities - Fair value	16,871	18,593
Foreign exchange contracts \| Financial Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	219,671	145,197
Gross amounts recognized	1,575	1,230
Derivative liabilities - Fair value	1,083	273
Foreign exchange contracts \| Financial Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	892,913	1,191,355
Gross amounts recognized	8,052	10,049
Derivative liabilities - Fair value	2,405	3,658
Foreign exchange contracts \| Financial Counterparty \| Purchased options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	118,350	117,729
Gross amounts recognized	31	574
Derivative liabilities - Fair value	0	0
Foreign exchange contracts \| Financial Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,135
Gross amounts recognized	0
Derivative liabilities - Fair value	1
Foreign exchange contracts \| Financial Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	1,233,069	1,454,281
Gross amounts recognized	9,658	11,853
Derivative liabilities - Fair value	$ 3,489	$ 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://www.xbrl.org/2003/role/disclosureRef
-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

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

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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=125515794&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=125515794&loc=SL5579245-113959

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