Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative assets - Fair value	$ 107,816	$ 67,077
Derivative liabilities - Fair Value	118,305	75,838
Foreign exchange contracts
Derivative [Line Items]
Notional amount		95,200
Derivative instruments not designated as hedging instruments
Derivative [Line Items]
Notional amount	15,222,341	10,153,108
Derivative assets - Fair value	107,816	67,077
Derivative liabilities - Fair Value	111,828	69,068
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	3,407,522	770,215
Derivative assets - Fair value	21,624	5,840
Derivative liabilities - Fair Value	19,329	10,170
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	2,023,425	163,389
Derivative assets - Fair value	11,719	2,189
Derivative liabilities - Fair Value	13,079	752
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	21,108	4,318
Derivative assets - Fair value	348	0
Derivative liabilities - Fair Value	243	98
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Written options
Derivative [Line Items]
Notional amount	537
Derivative assets - Fair value	16
Derivative liabilities - Fair Value	0
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount	83,864
Derivative assets - Fair value	0
Derivative liabilities - Fair Value	370
Foreign exchange contracts \| Customer Counterparty \| Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	2,128,934	167,707
Derivative assets - Fair value	12,083	2,189
Derivative liabilities - Fair Value	13,692	850
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Forwards and spot
Derivative [Line Items]
Notional amount	506,342	155,872
Derivative assets - Fair value	3,407	662
Derivative liabilities - Fair Value	2,285	7,800
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Swaps
Derivative [Line Items]
Notional amount	687,845	446,636
Derivative assets - Fair value	5,764	2,989
Derivative liabilities - Fair Value	3,336	1,520
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Purchased options
Derivative [Line Items]
Notional amount	537
Derivative assets - Fair value	0
Derivative liabilities - Fair Value	16
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Collars
Derivative [Line Items]
Notional amount	83,864
Derivative assets - Fair value	370
Derivative liabilities - Fair Value	0
Foreign exchange contracts \| Financial Counterparty \| Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative [Line Items]
Notional amount	1,278,588	602,508
Derivative assets - Fair value	9,541	3,651
Derivative liabilities - Fair Value	$ 5,637	$ 9,320

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

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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No definition available.

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