Derivative Instruments and Hedging Activities - Summary of Company's Outstanding Derivatives (Detail) ₨ in Millions, $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) Instruments	Sep. 30, 2021 INR (₨) Instruments
Designated as Hedging Instrument [Member] \| Currency Forward Agreements [Member]
Derivative [Line Items]
Number of Instruments \| Instruments	3	3
Designated as Hedging Instrument [Member] \| Currency Forward Agreements [Member] \| Short [Member]
Derivative [Line Items]
Notional amount \| $	$ 4.2
Designated as Hedging Instrument [Member] \| Currency Forward Agreements [Member] \| Long [Member]
Derivative [Line Items]
Notional amount \| ₨		₨ 331.0
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Number of Instruments \| Instruments	1	1
Effective Date	Jun. 30, 2021
Maturity Date	Jun. 30, 2022
Notional amount, Liability \| $	$ 308.0

Date the entity entered into the derivative contract, in YYYY-MM-DD format.

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

Reference 2: 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 3: 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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- 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

Date the derivative contract matures, in YYYY-MM-DD format.

+ References

No definition available.

+ Details

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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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- 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
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-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

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