Document And Entity Information [Abstract] Document And Entity Information [Abstract] Statement [Table] Statement [Line Items] Document Type Amendment Flag Document Period End Date Document Fiscal Year Focus Document Fiscal Period Focus Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Entity Common Stock, Shares Outstanding Consolidated Balance Sheets [Abstract] Assets Abstract Assets Cash and cash equivalents Cash and cash equivalents, end of period Cash and cash equivalents, beginning of period Cash and Cash Equivalents, at Carrying Value, Total Short-term investments Short-term Investments, Total Restricted Cash and Equivalents, Current Restricted cash Accounts receivable, net of allowance for doubtful accounts of $xxxx at June 30, 2011 and $246 at December 31, 2010 Accounts receivable, net Accounts Receivable, Net, Current, Total Prepaid Expense, Current Prepaid expenses Prepaid Expense, Current, Total Deferred Tax Assets Net Current Deferred Tax Assets, Net, Current, Ending Balance Deferred Tax Assets, Net, Current, Beginning Balance Deferred tax assets, net Deferred Tax Assets, Net, Current, Total Carrying amount as of the balance sheet date of payments made in advance for income and other taxes, which will be charged against earnings within one year or the normal operating cycle, if longer, net of carrying amount as of the balance sheet date of the unpaid sum of known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations. Advance Income-Tax, Net Advance income tax, net Other Assets, Current Other current assets Assets, Current Total current assets Property, Plant and Equipment, Net Property, Plant and Equipment, Net, Ending Balance Property, Plant and Equipment, Net, Beginning Balance Fixed assets, net Property, Plant and Equipment, Net, Total Restricted cash Deferred tax assets, net Deferred Tax Assets, Net, Noncurrent, Total Intangible assets, net of amortization Intangible assets, net Intangible Assets, Net (Excluding Goodwill), Total Goodwill Goodwill, Ending Balance Goodwill, Beginning Balance Goodwill, Total Other Assets Noncurrent Other assets Other Assets, Noncurrent, Total Assets Total assets Liabilities and Stockholders' Equity Accounts payable Accounts Payable, Current, Total Deferred Revenue Current Deferred revenue Deferred Revenue, Current, Total Accrued employee cost Employee-related Liabilities, Current, Total Accrued Liabilities Current Accrued expenses and other current liabilities Accrued Liabilities, Current, Total Capital Lease Obligations, Current Current portion of capital lease obligations Liabilities, Current Total current liabilities Capital Lease Obligations, Noncurrent Capital lease obligations, less current portion Total obligations incurred as part of normal operations that is expected to be repaid beyond the following twelve months or one business cycle and include FIN 48 reserves. Liabilities Including FIN 48 Reserve Noncurrent Non-current liabilities Liabilities Total liabilities Commitments and contingencies, Liabilities Commitments and contingencies Dollar value of issued preference shares, whether issued at par value, no par or stated value and includes all nature of preference shares (including but not limited to convertible, non convertible, redeemable preference shares) Preferred Stock, Value Issued Preferred stock, $0.001 par value; 15,000,000 shares authorized, none issued Stockholders' equity: Common Stock, Value, Issued Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued, Beginning Balance Common stock, $0.001 par value; 100,000,000 shares authorized, 31,880,218 shares issued and 31,549,366 shares outstanding as of March 31, 2012 and 31,496,461 shares issued and 31,173,064 shares outstanding as of December 31, 2011. Common Stock, Value, Issued, Total Additional paid-in-capital Additional Paid in Capital, Ending Balance Additional Paid in Capital, Beginning Balance Additional paid-in capital Retained earnings Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit), Beginning Balance Retained earnings Accumulated other comprehensive income/(loss) Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated other comprehensive loss Accumulated other comprehensive income/(loss) Total stockholders' equity including shares held in treasury Total stockholders' equity including shares held in treasury Total stockholders' equity including shares held in treasury Total stockholders' equity including shares held in treasury Less: 252,502 shares as of September 30, 2010 and 247,030 shares as of December 31, 2009, held in treasury, at cost Less: 330,852 shares as of March 31, 2012 and 323,397 shares as of December 31, 2011, held in treasury, at cost Treasury Stock, Value, Ending Balance Treasury Stock, Value, Beginning Balance Stockholders' Equity Attributable to Parent Stockholders' Equity Attributable to Parent, Ending Balance Stockholders' Equity Attributable to Parent, Beginning Balance ExlService Holdings, Inc. stockholders' equity Minority Interest Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance Stockholders' Equity Attributable to Noncontrolling Interest, Total Non-controlling interest Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Balance Balance Total stockholders' equity Total Liabilities and Stockholders' Equity Total liabilities and stockholders' equity Face amount or stated value per share of all nature of preference shares, (including but not limited to convertible, non convertible, redeemable preference shares); generally not indicative of the fair market value per share. Preferred Stock, Par Value Per Share Preferred stock, par value The maximum number of all preference shares, (including but not limited to convertible, non convertible, redeemable preference shares or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. Preferred Stock, Number of Shares Authorized Preferred stock, shares authorized Total number of all preference shares (including but not limited to convertible, non convertible, redeemable preference shares or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. Preferred Stock, Number of Shares Issued Preferred stock, shares issued Common stock, par value Common stock, shares authorized Common stock, shares issued Common Stock, Shares, Issued, Total Common stock, shares outstanding Balance, shares Balance, shares Treasury stock, shares Treasury Stock, Shares, Ending Balance Treasury Stock, Shares, Beginning Balance Consolidated Statements Of Income [Abstract] Sales Revenue Net Revenues Sales Revenue, Net, Total Cost of revenues (exclusive of depreciation and amortization) Cost of Revenue, Total Gross Profit Gross profit Operating expenses: General and administrative expenses General and Administrative Expense, Total Selling and marketing expenses Selling and Marketing Expense, Total Depreciation Depletion And Amortization Depreciation and amortization Depreciation and amortization Operating Expenses Total operating expenses Operating Income (Loss) Income from operations Nonoperating Income Expense Abstract Other income, net: Foreign exchange gain/(loss) Foreign exchange gain Foreign Currency Transaction Gain (Loss), before Tax, Total Other Nonoperating Income Expense Interest and other income, net Other Nonoperating Income (Expense), Total Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Cumulative Effects of Changes in Accounting Principles, Noncontrolling Interest Income before income taxes Income tax provision Income Tax Expense (Benefit), Total Net income Net income Earnings Per Share [Abstract] Earnings per share: Earnings Per Share Basic Basic Basic Earnings Per Share Diluted Diluted Diluted Weighted-average number of shares used in computing earnings per share: Basic Weighted Average Number of Shares Outstanding, Basic, Total Diluted Weighted Average Number of Shares Outstanding, Diluted, Total Consolidated Statements Of Comprehensive Income [Abstract] Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income: Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Unrealized gain/(loss) on effective cash flow hedges, net of taxes Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized (Gain) Loss Arising During Period, Net of Tax Retirement benefits, net of taxes Other Comprehensive Income (Loss), Net of Tax Total other comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Total comprehensive income/(loss) Total comprehensive income Consolidated Statements Of Cash Flow [Abstract] Cash flows from operating activities: Adjustments to reconcile net income to net cash provided by operating activities: Amortization of Financing Costs Amortization of debt issuance costs Share-based compensation expense Stock-based compensation expense Share-based compensation expense Non-employee stock options Unrealized foreign exchange gain Unrealized foreign exchange loss Deferred income taxes Deferred Income Tax Expense (Benefit), Total Change in operating assets and liabilities (net of effect of acquisitions): Change in operating assets and liabilities: Increase Decrease In Restricted Cash Restricted cash Restricted cash Increase (Decrease) in Restricted Cash, Total Accounts receivable Accounts receivable IncreaseDecrease In Prepaid Deferred Expense And Other Assets Prepaid expenses and other current assets Prepaid expenses and other current assets Prepaid expenses and other current assets Increase Decrease In Accounts Payable Accounts payable Accounts payable Deferred revenue Accrued employee costs Accrued employee cost Accrued employee cost Accrued employee cost Accrued expenses and other liabilities Increase (Decrease) in Other Operating Liabilities, Total Increase Decrease In Accrued Income Taxes Payable Advance income tax, net Other assets Other assets Increase (Decrease) in Other Operating Assets, Total Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Cash flows from investing activities: Purchase of fixed assets Purchase of fixed assets Purchase of fixed assets Purchase of short-term investments Purchase of short-term investments Proceeds from redemption of short-term investments Net Cash Provided by (Used in) Investing Activities Net cash used for investing activities Cash flows from financing activities: Principal payments on capital lease obligations Principal payments on capital lease obligations Acquisition of treasury stock Acquisition of treasury stock Proceeds from exercise of stock options Net Cash Provided by (Used in) Financing Activities Net cash provided by financing activities Effect of exchange rate changes on cash and cash equivalents Effect of exchange rate changes on cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Net (decrease)/increase in cash and cash equivalents Net (decrease)/increase in cash and cash equivalents Organization And Basis Of Presentation [Abstract] Organization Consolidation And Presentation Of Financial Statements Disclosure TextBlock Organization And Basis Of Presentation Summary Of Significant Accounting Policies [Abstract] Significant Accounting Policies [Text Block] Summary Of Significant Accounting Policies Earnings Per Share [Text Block] Earnings Per Share Segment Information [Abstract] Segment Reporting Disclosure [Text Block] Segment Information Business Combinations, Goodwill And Intangible Assets [Abstract] BusinessCombination Disclosure Text Block Business Combinations, Goodwill And Intangible Assets Fair Value Measurements [Abstract] Fair Value Disclosures [Text Block] Fair Value Measurements Derivatives And Hedge Accounting [Abstract] Derivative Instruments and Hedging Activities Disclosure [Text Block] Derivatives And Hedge Accounting Fixed Assets [Abstract] Property, Plant and Equipment Disclosure [Text Block] Fixed Assets Capital Structure [Abstract] Capital Structure [Text Block] Capital Structure [Text Block] Capital Structure Employee Benefit Plans [Abstract] Pension and Other Postretirement Benefits Disclosure [Text Block] Employee Benefit Plans Leases [Abstract] Leases of Lessee Disclosure [Text Block] Leases Income Taxes [Abstract] Income Tax Disclosure [Text Block] Income Taxes Stock-Based Compensation [Abstract] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-Based Compensation Related Party Transactions [Abstract] dup_1_Related Party Transaction, Due from (to) Related Party, Noncurrent, Total Related Party Transactions Disclosure [Text Block] Related Party Transactions Geographical Information [Abstract] This element may be used to disclose in the entity's country of domicile and its entirety the names of foreign countries from which revenue is material and the amount of revenue from external customers attributed to those countries. An entity may also provide subtotals of geographic information about groups of countries. This element also include amount of long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets, located in the entity's country of domicile and in foreign countries in total in which the entity holds assets. Geographical Information [Text Block] Geographical Information Commitments And Contingencies [Abstract] Commitments and Contingencies Disclosure [Text Block] Commitments And Contingencies