Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative assets - Fair value	$ 694,010	$ 602,754
Derivative liabilities - Fair value	561,788	424,828
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	20,874,985	21,341,158
Derivative assets - Fair value	693,852	602,754
Derivative liabilities - Fair value	560,639	422,729
Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	3,047,846	3,108,488
Derivative assets - Fair value	31,717	30,300
Derivative liabilities - Fair value	24,313	22,524
Foreign exchange contracts \| Customer Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	1,573,945	1,522,888
Derivative assets - Fair value	18,558	17,575
Derivative liabilities - Fair value	20,340	17,928
Foreign exchange contracts \| Customer Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	66,696	13,590
Derivative assets - Fair value	321	872
Derivative liabilities - Fair value	76	91
Foreign exchange contracts \| Customer Counterparty \| Written options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	169,434	117,729
Derivative assets - Fair value	22	0
Derivative liabilities - Fair value	10	574
Foreign exchange contracts \| Customer Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,084
Derivative assets - Fair value	0
Derivative liabilities - Fair value	8
Foreign exchange contracts \| Customer Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	1,812,159	1,654,207
Derivative assets - Fair value	18,901	18,447
Derivative liabilities - Fair value	20,434	18,593
Foreign exchange contracts \| Financial Counterparty \| Forwards and spot \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	249,814	145,197
Derivative assets - Fair value	1,913	1,230
Derivative liabilities - Fair value	1,653	273
Foreign exchange contracts \| Financial Counterparty \| Swaps \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	814,355	1,191,355
Derivative assets - Fair value	10,885	10,049
Derivative liabilities - Fair value	2,204	3,658
Foreign exchange contracts \| Financial Counterparty \| Purchased options \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	169,434	117,729
Derivative assets - Fair value	10	574
Derivative liabilities - Fair value	22	0
Foreign exchange contracts \| Financial Counterparty \| Collars \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	2,084
Derivative assets - Fair value	8
Derivative liabilities - Fair value	0
Foreign exchange contracts \| Financial Counterparty \| Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	1,235,687	1,454,281
Derivative assets - Fair value	12,816	11,853
Derivative liabilities - Fair value	$ 3,879	$ 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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