Document and Entity Information [Abstract] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Marketable securities Marketable Securities, Current Accounts receivable, net of allowance Accounts Receivable, Net, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current, Total Total current assets Property and equipment, net Property, Plant and Equipment, Net Other assets Other Assets, Noncurrent Acquired intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Goodwill Total assets Assets, Total Total assets Liabilities and Stockholders' Equity Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued expenses Accrued Liabilities, Current Current portion of deferred revenue Deferred Revenue, Current Total current liabilities Liabilities, Current, Total Total current liabilities Deferred revenue, net of current portion Deferred Revenue, Noncurrent Other long-term liabilities Other Liabilities, Noncurrent Commitments and contingencies (Note 8) Commitments and Contingencies Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.01 par value; 6,000,000 shares authorized; no shares issued Preferred Stock, Value, Issued Preferred Stock, par value Preferred stock, par value Preferred Stock, shares authorized Preferred stock, shares authorized Preferred Stock, shares issued Preferred stock, shares issued Common stock, $0.01 par value; 45,000,000 shares authorized; 25,411,472 and 25,137,342 outstanding at March 31, 2012 and December 31, 2011, respectively Common Stock, Value, Issued Common Stock, par value Common stock, par value Common Stock, shares authorized Common stock, shares authorized Common Stock, shares, outstanding Common stock, shares outstanding Additional paid-in capital Additional Paid in Capital Accumulated deficit Retained Earnings (Accumulated Deficit) Treasury stock, at cost (2,009 shares) Treasury Stock, Value Treasury stock, at cost (2,009 shares) Treasury Stock, shares Treasury stock, shares Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders' equity Stockholders' Equity Attributable to Parent, Total Total stockholders' equity Liabilities Temporary Equity and Stockholders Equity Total liabilities and stockholders' equity Total liabilities and stockholders' equity Total liabilities and stockholders' equity Revenue Revenues Cost of revenue Cost of Revenue Gross profit Gross Profit Gross profit Operating expenses: Operating Expenses [Abstract] Research and development Research and Development Expense General and administrative General and Administrative Expense Sales and marketing Selling and Marketing Expense Lease Exit Charge Lease exit charge Lease exit charge Total operating expenses Operating Expenses, Total Total operating expenses Loss from operations Operating Income (Loss) Loss from operations Interest and other income (expense), net Interest and Other Income Loss before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Loss before income taxes Provision for income taxes Income Tax Expense (Benefit) Provision for income taxes Net loss Net Income (Loss) Attributable to Parent Net loss Accretion of redeemable convertible preferred stock Temporary Equity, Accretion to Redemption Value Net loss attributable to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Net loss attributable to common stockholders Basic and diluted net loss per share attributable to common stockholders Earnings Per Share, Basic and Diluted Weighted Average Shares Outstanding Basic and Diluted Weighted-average number of common shares used in computing basic and diluted net loss per share Weighted-average number of common shares used in computing basic and diluted net loss per share Other comprehensive income: Other Comprehensive Income (Loss), Net of Tax [Abstract] Net Unrealized Gains on Marketable Securities Net unrealized gains on marketable securities Net unrealized gains on marketable securities Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Total other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Total Total other comprehensive income Total comprehensive loss Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest, Total Total comprehensive loss Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Net loss Adjustments to reconcile net loss to net cash from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Amortization of Premium on Investments Amortization of premium on marketable securities Amortization of premium on marketable securities Stock-based compensation expense Share-based Compensation Provision for (recovery of) bad debt Provision for Doubtful Accounts Non Cash Lease Exit Charge Non-cash lease exit charge Non-cash lease exit charge Re Measurement of Preferred Stock Warrant Liability Re-measurement of preferred stock warrant liability Re-measurement of preferred stock warrant liability Re-measurement of preferred stock warrant liability Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Accounts receivable Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Prepaid expenses and other current assets Other assets Increase (Decrease) in Other Operating Assets Other assets Accounts payable Increase (Decrease) in Accounts Payable Accrued expenses Increase (Decrease) in Accrued Liabilities Other long-term liabilities Increase (Decrease) in Other Noncurrent Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Purchases of property and equipment Proceeds from maturities of marketable securities Proceeds from Sale of Short-term Investments Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Net cash used in investing activities Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from exercise of stock options Proceeds from Stock Options Exercised Repurchase of common stock Payments for Repurchase of Common Stock Repurchase of common stock Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net cash provided by financing activities Effect of currency exchange rate changes on cash Effect of Exchange Rate on Cash and Cash Equivalents Net decrease in cash Cash and Cash Equivalents, Period Increase (Decrease) Net decrease in cash Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Non-cash investing and financing activities Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Accretion of redeemable convertible preferred stock Nature of Business Nature of Operations [Text Block] Nature of Business [Abstract] Nature of Business [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Summary of Significant Accounting Policies [Abstract] Summary of Significant Accounting Policies [Abstract] Net Loss per Share Earnings Per Share [Text Block] Net Loss Per Share [Abstract] Net Loss Per Share [Abstract] Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Fair Value of Financial Instruments [Abstract] Fair Value of Financial Instruments [Abstract] Accrued Expenses Accounts Payable and Accrued Liabilities Disclosure [Text Block] Accrued Expenses [Abstract] Accrued Expenses [Abstract] Stock-based Awards Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-based Awards [Abstract] Stock-based Awards [Abstract] Income Taxes Income Tax Disclosure [Text Block] Income Taxes [Abstract] Income Taxes [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies [Abstract] Commitments and Contingencies [Abstract] Revolving Credit Facility Short-term Debt [Text Block] Revolving Credit Facility [Abstract] Revolving Credit Facility [Abstract] Intangible Assets and Goodwill Goodwill and Intangible Assets Disclosure [Text Block] Intangible Assets and Goodwill [Abstract] Intangible Assets and Goodwill [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Related Party Transactions [Abstract] Related Party Transactions [Abstract] Amendment Flag Current Fiscal Year End Date Document Period End Date Document Type Entity Central Index Key Entity Common Stock, Shares Outstanding Entity Filer Category Entity Registrant Name Document Fiscal Period Focus Document Fiscal Year Focus Condensed Consolidated Balance Sheets [Abstract] Condensed Consolidated Statements of Operations [Abstract] Condensed Consolidated Statements of Comprehensive Loss [Abstract] Condensed Consolidated Statements of Cash Flows [Abstract]