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Employee Benefit Plans - Schedule of weighted average assumptions used to determine plan costs, Gratuity Plan (Detail) - Gratuity Plan costs	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Expected long term rate of return on plan assets per annum (in percentage)		7.50%	7.50%
Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rate (in percentage)	4.45%	6.80%	8.30%
Rate of increase in compensation per annum (in percentage)	5.20%	5.20%	5.20%
Expected long term rate of return on plan assets per annum (in percentage)	7.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rate (in percentage)	5.90%	7.35%	8.40%
Rate of increase in compensation per annum (in percentage)	9.00%	11.50%	11.00%
Expected long term rate of return on plan assets per annum (in percentage)	7.50%

X

- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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X

- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

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X

- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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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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