Nominal or face amount used to calculate payment on derivative.

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=109980867&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=109980867&loc=SL5579245-113959

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

+ Details

Name:	us-gaap_ForeignCurrencyContractAssetFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

+ Details

Name:	us-gaap_ForeignCurrencyContractsLiabilityFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
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Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

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- Details

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Fair Value of Financial Instruments - Derivatives (Details) $ in Thousands, € in Millions, ₨ in Millions, £ in Millions	Jun. 30, 2020 USD ($) contract	Jun. 30, 2020 EUR (€) contract	Jun. 30, 2020 GBP (£) contract	Jun. 30, 2020 INR (₨) contract	Dec. 31, 2019 USD ($) contract	Dec. 31, 2019 EUR (€) contract	Dec. 31, 2019 GBP (£) contract	Dec. 31, 2019 INR (₨) contract
Derivatives, Fair Value [Line Items]
Foreign currency contract, asset, fair value disclosure	$ 862				$ 942
Foreign Currency Contracts, Liability, Fair Value Disclosure	(1,111)				(1,074)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Foreign currency contract, asset, fair value disclosure	409				515
Foreign Currency Contracts, Liability, Fair Value Disclosure	(309)				(550)
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Foreign currency contract, asset, fair value disclosure	453				427
Foreign Currency Contracts, Liability, Fair Value Disclosure	$ (802)				$ (524)
Foreign Currency Contract, INR [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| ₨				₨ 351.7				₨ 756.0
Foreign Currency Contract, INR [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| ₨				₨ 1,590.0
Forward Contracts \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, number of instruments held \| contract	15	15	15	15	15	15	15	15
Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, number of instruments held \| contract	39	39	39	39	26	26	26	26
Foreign Currency Contract, Euro [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| €		€ 12.5				€ 20.0
Foreign Currency Contract, Euro [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| €		€ 21.8				€ 24.2
Foreign Currency Contract, Pound [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| £			£ 7.9				£ 5.6
Foreign Currency Contract, Pound [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| £			£ 9.2				£ 9.7