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increase in repurchase amount, 2019 Stock Repurchase Program, Authorized Increase in Repurchase Amount Per Period, Year Three Stock Repurchase Program, Authorized Increase in Repurchase Amount Per Period, Year Three Owned assets, gross Property, Plant and Equipment, Gross, Excluding Capital Leased Assets Capitalized Contract Cost [Table] Capitalized Contract Cost [Table] Earnings per share attributable to ExlService Holdings, Inc. stockholders: Earnings Per Share [Abstract] Total finance lease liabilities Present value of lease liabilities Finance Lease, Liability Unrealized foreign exchange (gain)/loss, net Foreign Currency Transaction Gain (Loss), Unrealized Retirement benefits Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Reclassification from AOCI, before tax Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Translation adjustment, if any Accounts Receivable, Allowance for Credit Loss, Foreign Currency Translation Accounts 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