Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative assets - Fair value	$ 602,754	$ 330,316
Derivative liabilities - Fair Value	424,828	256,528
Derivative instruments not designated as hedging instruments
Derivative [Line Items]
Notional amount	21,341,158	20,540,031
Derivative assets - Fair value	602,754	330,316
Derivative liabilities - Fair Value	422,729	251,744
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	3,108,488	4,839,661
Derivative assets - Fair value	30,300	54,637
Derivative liabilities - Fair Value	22,524	47,024
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	1,522,888	3,581,036
Derivative assets - Fair value	17,575	45,911
Derivative liabilities - Fair Value	17,928	40,591
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	13,590	6,889
Derivative assets - Fair value	872	16
Derivative liabilities - Fair Value	91	84
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Written options
Derivative [Line Items]
Notional amount	117,729	87,036
Derivative assets - Fair value	0	127
Derivative liabilities - Fair Value	574	0
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount		2,244
Derivative assets - Fair value		0
Derivative liabilities - Fair Value		14
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	1,654,207	3,677,205
Derivative assets - Fair value	18,447	46,054
Derivative liabilities - Fair Value	18,593	40,689
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	145,197	207,492
Derivative assets - Fair value	1,230	1,400
Derivative liabilities - Fair Value	273	507
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	1,191,355	702,391
Derivative assets - Fair value	10,049	6,156
Derivative liabilities - Fair Value	3,658	4,712
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Purchased options
Derivative [Line Items]
Notional amount	117,729	87,036
Derivative assets - Fair value	574	0
Derivative liabilities - Fair Value	0	127
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount		165,537
Derivative assets - Fair value		1,027
Derivative liabilities - Fair Value		989
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	1,454,281	1,162,456
Derivative assets - Fair value	11,853	8,583
Derivative liabilities - Fair Value	$ 3,931	$ 6,335

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.

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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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