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Long-Term Debt - Schedule of long term debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023	Mar. 31, 2021	Nov. 30, 2019
Debt Instrument [Line Items]
Long-term debt, amount	$ 1,633,528	$ 1,256,962
Current portion	425,918	432,242
Non-current portion	1,207,610	824,720
Total	1,633,528	1,256,962
Term loan
Debt Instrument [Line Items]
Long-term debt, amount	489,167	508,867
Total	489,167	508,867
2019 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	399,754	399,464
Total	399,754	399,464
2021 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	348,931	348,631
Total	348,931	348,631
2024 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	395,676	0
Total	395,676	0
Genpact Luxembourg S.r.l. \| 2019 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	399,754	399,464
Total	$ 399,754	399,464
Interest rate on senior notes (in percentage)	3.375%			3.375%
Genpact Luxembourg S.r.l. \| 2021 Senior notes
Debt Instrument [Line Items]
Long-term debt, amount	$ 348,931	348,631
Total	$ 348,931	$ 348,631
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%