Long-Term Debt - Schedule of long term debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024	Mar. 31, 2021
Debt Instrument [Line Items]
Long-term debt, amount	$ 1,209,087	$ 1,221,440
Current portion	375,714	26,173
Non-current portion	833,373	1,195,267
Total	1,209,087	1,221,440
Term loan
Debt Instrument [Line Items]
Long-term debt, amount	463,002	476,089
Total	463,002	476,089
2021 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	349,532	349,234
Total	349,532	349,234
2024 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	396,553	396,117
Total	396,553	396,117
Genpact Luxembourg S.r.l. \| 2021 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	349,532	349,234
Total	$ 349,532	$ 349,234
Interest rate on senior notes (in percentage)	1.75%		1.75%
Genpact Luxembourg S.r.l. \| 2024 Senior notes
Debt Instrument [Line Items]
Interest rate on senior notes (in percentage)	6.00%

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.

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+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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