Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative assets - Fair value	$ 764,430	$ 330,316
Derivative liabilities - Fair value	560,169	256,528
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional amount	20,113,400	20,540,031
Derivative assets - Fair value	764,185	330,316
Derivative liabilities - Fair value	558,512	251,744
Derivatives not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	2,738,018	4,839,661
Derivative assets - Fair value	24,044	54,637
Derivative liabilities - Fair value	19,741	47,024
Foreign exchange contracts \| Customer Counterparty \| Derivatives not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	1,768,864	3,581,036
Derivative assets - Fair value	17,940	45,911
Derivative liabilities - Fair value	14,246	40,591
Foreign exchange contracts \| Customer Counterparty \| Derivatives not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	7,160	6,889
Derivative assets - Fair value	0	16
Derivative liabilities - Fair value	42	84
Foreign exchange contracts \| Customer Counterparty \| Derivatives not designated as hedging instruments \| Written options
Derivative [Line Items]
Notional amount		87,036
Derivative assets - Fair value		127
Derivative liabilities - Fair value		0
Foreign exchange contracts \| Customer Counterparty \| Derivatives not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount	1,685	2,244
Derivative assets - Fair value	2	0
Derivative liabilities - Fair value	0	14
Foreign exchange contracts \| Customer Counterparty \| Derivatives not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	1,777,709	3,677,205
Derivative assets - Fair value	17,942	46,054
Derivative liabilities - Fair value	14,288	40,689
Foreign exchange contracts \| Financial Counterparty \| Derivatives not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	62,424	207,492
Derivative assets - Fair value	62	1,400
Derivative liabilities - Fair value	98	507
Foreign exchange contracts \| Financial Counterparty \| Derivatives not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	734,640	702,391
Derivative assets - Fair value	4,502	6,156
Derivative liabilities - Fair value	3,808	4,712
Foreign exchange contracts \| Financial Counterparty \| Derivatives not designated as hedging instruments \| Purchased options
Derivative [Line Items]
Notional amount		87,036
Derivative assets - Fair value		0
Derivative liabilities - Fair value		127
Foreign exchange contracts \| Financial Counterparty \| Derivatives not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount	162,245	165,537
Derivative assets - Fair value	1,538	1,027
Derivative liabilities - Fair value	1,547	989
Foreign exchange contracts \| Financial Counterparty \| Derivatives not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	959,309	1,162,456
Derivative assets - Fair value	6,102	8,583
Derivative liabilities - Fair value	$ 5,453	$ 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.

+ 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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