Document and Entity Information [Abstract] Document and entity information. 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, at Carrying Value Cash and cash equivalents, end of period Cash and cash equivalents, beginning of period Cash and cash equivalents Short-term Investments Short-term investments Restricted Cash and Cash Equivalents, Current Restricted cash Accounts Receivable, Net, Current Accounts receivable, net Prepaid Expense, Current Prepaid expenses Deferred Tax Assets, Net of Valuation Allowance, Current Deferred tax assets, net Advance Income Tax, Net Advance income tax, net 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. Other Assets, Current Other current assets Assets, Current Total current assets Property, Plant and Equipment, Net Fixed assets, net Fixed assets, net Total Fixed assets Restricted Cash and Cash Equivalents, Noncurrent Restricted cash Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Deferred tax assets, net Intangible Assets, Net (Excluding Goodwill) Intangible assets, net Goodwill Balance at June 30,2012 Balance at January 1,2011 Goodwill Other Assets, Noncurrent Other assets Assets Total assets Liabilities and Equity [Abstract] Liabilities and Stockholders' Equity Accounts Payable, Current Accounts payable Deferred Revenue, Current Deferred revenue Employee-related Liabilities, Current Accrued employee cost Accrued Liabilities, Current Accrued expenses and other current liabilities Accrued expenses and other current liabilities Capital Lease Obligations, Current Less: current portion Current portion of capital lease obligations Liabilities, Current Total current liabilities Capital Lease Obligations, Noncurrent Long term capital lease obligation Capital lease obligations, less current portion Liabilities Including FIN 48 Reserve Noncurrent Non-current liabilities 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 Total liabilities Commitments and contingencies Commitments and contingencies Preferred Stock, Value Issued 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, $0.001 par value; 15,000,000 shares authorized, none issued Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Stockholders' equity: Common Stock, Value, Issued Common stock, $0.001 par value; 100,000,000 shares authorized, 32,309,413 shares issued and 31,973,151 shares outstanding as of June 30, 2012 and 31,496,461 shares issued and 31,173,064 shares outstanding as of December 31, 2011 Additional Paid in Capital Additional paid-in-capital Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive loss Treasury Stock, Value Less: 336,262 shares as of June 30, 2012 and 323,397 shares as of December 31, 2011, held in treasury, at cost Less: 0 shares as of June 30, 2012 and 323,397 shares as of December 31, 2011, held in treasury, at cost Stockholders' Equity Attributable to Parent ExlService Holdings, Inc. stockholders' equity Stockholders' Equity Attributable to Noncontrolling Interest Non-controlling interest Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total stockholders' equity Liabilities and Equity Total liabilities and stockholders' equity Preferred Stock, Par Value Per Share 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 Preferred Stock, Number of Shares Authorized 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, shares authorized Preferred Stock, Number of Shares Issued 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, shares issued Common Stock, Par or Stated Value Per Share Common stock, par value Common Stock, Shares Authorized Common stock, shares authorized Common Stock, Shares, Issued Common stock, shares issued Common Stock, Shares, Outstanding Common stock, shares outstanding Treasury Stock, Shares Treasury stock, shares Consolidated Statements of Income [Abstract] Revenue, Net Total Revenues Revenues Cost of Revenue Cost of revenues (exclusive of depreciation and amortization) Gross Profit Gross profit Operating Expenses [Abstract] Operating expenses: General and Administrative Expense General and administrative expenses Selling and Marketing Expense Selling and marketing expenses Depreciation, Depletion and Amortization Depreciation and amortization Operating Expenses Total operating expenses Operating expenses Operating Income (Loss) Income from operations Nonoperating Income (Expense) [Abstract] Other income, net: Foreign Currency Transaction Gain (Loss), before Tax Foreign exchange (loss)/gain Other Nonoperating Income (Expense) Interest and other income, net Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Income before income taxes Income Tax Expense (Benefit) Income tax expense Income tax provision Net Income (Loss) Attributable to Parent Net income Net income Earnings Per Share [Abstract] Earnings per share: Earnings Per Share, Basic Basic Earnings Per Share, Diluted Diluted Weighted Average Number of Shares Outstanding, Diluted [Abstract] Denominators: Weighted-average number of shares used in computing earnings per share: Weighted Average Number of Shares Outstanding, Basic Basic Basic weighted average common shares outstanding Weighted Average Number of Shares Outstanding, Diluted Diluted Diluted weighted average common shares outstanding 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), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax Retirement benefits, net of taxes Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Total comprehensive (loss)/ income Consolidated Statements of Cash Flow [Abstract] Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Share-based Compensation Stock-based compensation expense Share-based Goods and Nonemployee Services Transaction, Expense Non-employee stock options Foreign Currency Transaction Gain (Loss), Unrealized Unrealized foreign exchange loss Deferred Income Tax Expense (Benefit) Deferred income taxes Increase (Decrease) in Operating Capital [Abstract] Change in operating assets and liabilities: Increase (Decrease) in Restricted Cash Restricted cash Increase (Decrease) in Accounts Receivable Accounts receivable Increase (Decrease) in Prepaid Expense and Other Assets Prepaid expenses and other current assets Increase (Decrease) in Accounts Payable Accounts payable Increase (Decrease) in Deferred Revenue Deferred revenue Increase (Decrease) in Other Employee Related Liabilities Accrued employee cost Increase (Decrease) in Other Operating Liabilities Accrued expenses and other liabilities Increase (Decrease) in Income Taxes Payable Advance income tax, net Increase (Decrease) in Other Operating Assets Other assets Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities: Payments to Acquire Property, Plant, and Equipment Purchase of fixed assets Payments to Acquire Short-term Investments Purchase of short-term investments Proceeds from Sale 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 Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities: Repayments of Long-term Capital Lease Obligations Principal payments on capital lease obligations Payments for Repurchase of Common Stock Acquisition of treasury stock Proceeds from Stock Options Exercised Proceeds from exercise of stock options Net Cash Provided by (Used in) Financing Activities Net cash provided by financing activities Effect of Exchange Rate on Cash and Cash Equivalents Effect of exchange rate changes on cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Net increase/(decrease) in cash and cash equivalents Organization and Basis of Presentation [Abstract] Organization and Basis of Presentation [Text Block] Organization and Basis of Presentation Summary of Significant Accounting Policies [Abstract] 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] Business Combination Disclosure [Text Block] Business Combinations, Goodwill and Intangible Assets Fair Value Measurements [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 The changes in capital structure of the Company. 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] Related Party Transactions Disclosure [Text Block] Related Party Transactions Geographical Information [Abstract] Geographical Information [Text Block] 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 Commitments and Contingencies [Abstract] Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation adjustment Other Comprehensive Income (Loss), Net of Tax Total other comprehensive (loss)/ income Consolidation, Policy [Policy Text Block] Principles of Consolidation Use of Estimates, Policy [Policy Text Block] Use of Estimates New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Pronouncements Derivative Instruments and Hedges, Liabilities Derivative instruments Other Liabilities, Current Other current liabilities Derivative Instruments and Hedges, Liabilities, Noncurrent Derivative instruments Deferred Rent Credit, Noncurrent Deferred rent Other Liabilities, Noncurrent Other non-current liabilities Net Income (Loss) Attributable to Parent [Abstract] Numerators: Accounts Payable and Accrued Liabilities, Current [Abstract] Summary of accrued expenses and other current liabilities Liabilities, Noncurrent [Abstract] Summary of non-current liabilities Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table] Outsourcing Services [Member] Outsourcing services. Outsourcing Services [Member] Transformation Services [Member] Transformation services. Transformation Services [Member] Table for Revenues and Cost of Revenues for Company's Outsourcing Services and Transformation Services Segments [Abstract] Table for Revenues and cost of revenues for Company's outsourcing services and transformation services segments Table for revenues and cost of revenues for company's outsourcing services and transformation services segments. Other Operating Income (Expense), Net Other income, net Products and Services [Axis] Products and Services [Domain] Revenue from External Customer [Line Items] Schedule of Goodwill [Table Text Block] Summary of Company's goodwill Summary of the Company's goodwill Business Acquisition, Purchase Price Allocation, Goodwill [Abstract] Goodwill, Translation Adjustments Currency translation adjustments Goodwill, Acquired During Period Goodwill arising from OPI Acquisition Trade Names and Trademarks [Member] Trade names and trademarks. Trade names and trademarks [Member] Noncompete Agreements [Member] Non-compete agreements [Member] Developed Technology Rights [Member] Developed technology [Member] Lease Agreements [Member] Leasehold benefits [Member] Customer Relationships [Member] Customer relationships [Member] Finite-Lived Intangible Assets, Gross Gross Carrying Amount Finite-Lived Intangible Assets, Accumulated Amortization Accumulated Amortization Finite-Lived Intangible Assets, Net Net Carrying Amount Schedule of Expected Amortization Expense [Table Text Block] Estimated amortization of intangible assets Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Estimated amortization of intangible assets Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2013 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2014 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2015 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Five 2017 Business Combinations Goodwill and Intangible Assets (Textual) [Abstract] Business combinations, goodwill and intangible assets. Business Combinations, Goodwill and Intangible Assets (Textual) [Abstract] Amortization of Intangible Assets Amortization expense Indefinite Life Trade Names and Trademarks Indefinite life trade names and trademarks. Indefinite life trade names and trademarks Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Acquired Finite-Lived Intangible Assets [Line Items] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Assets and Liabilities Measured at Fair Value Fair Value, Inputs, Level 1 [Member] Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Level 2 [Member] Fair Value, Inputs, Level 3 [Member] Level 3 [Member] Liabilities, Fair Value Disclosure Total Schedule of Foreign Exchange Contracts, Statement of Financial Position [Table Text Block] Summary of fair value of the foreign currency exchange contracts