Document And Entity Information Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Current Fiscal Year End Date Is Entity a Well-known Seasoned Issuer? Is Entity a Voluntary Filer? Is Entity's Reporting Status Current? Entity Filer Category Entity Public Float Entity Common Stock, Shares Outstanding Document Fiscal Period Focus Document Fiscal Year Focus Statement of Financial Position [Abstract] ASSETS Current assets: Cash and cash equivalents Marketable securities Accounts receivable Prepaid expenses and other current assets Total current assets Property and equipment, net Other assets Total assets LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities: Accounts payable Accrued liabilities Income tax payable Deferred revenue - current portion Total current liabilities Deferred revenue - non-current portion Deferred rent Total liabilities Commitments and contingencies (Note 6) Stockholders' equity: Preferred stock, $0.0001 par value; 1,000,000 shares authorized at December 31 and June 30, 2011; no shares issued and outstanding Common stock, $0.0001 par value; 150,000,000 and 100,000,000 authorized at December 31 and June 30, 2011; shares issued and outstanding - 68,732,939 and 67,915,865 at December 31 and June 30, 2011 Additional paid-in capital Accumulated other comprehensive loss Deficit accumulated during development stage Accumulated deficit Total stockholders' equity Total liabilities and stockholders' equity Preferred stock, par value Preferred stock, shares authorized Preferred stock, shares issued Preferred stock, shares outstanding Common stock, par value Common stock, shares authorized Common stock, shares issued Common stock, shares outstanding Income Statement [Abstract] Revenues: License and milestone revenues Collaboration services revenues Total revenues Operating expenses: Research and development General and administrative Total operating expenses Income (loss) from operations Interest income Interest expense and other income (expense), net Income (loss) before income taxes Income tax provision Net income (loss) Net income (loss) per share: Basic Diluted Weighted average shares used to compute net income (loss) per share: Basic Diluted Statement of Cash Flows [Abstract] Cash flows from operating activities: Net income (loss) Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities: Depreciation and amortization Amortization of premium/discount on marketable securities, net Share-based compensation expense Loss on property and equipment Changes in assets and liabilities: Accounts receivable Prepaid expenses and other assets Accounts payable Accrued liabilities Income taxes payable Deferred revenue Deferred rent Net cash provided by (used in) operating activities Cash flows from investing activities: Purchase of property and equipment (Payments for) proceeds from disposal or sale of property and equipment Purchase of marketable securities Proceeds from maturities of marketable securities Net cash provided by (used in) investing activities Cash flows from financing activities: Issuance of common stock, net of issuance costs Exercise of stock options and stock purchase rights Net cash provided by financing activities (Decrease)/Increase in cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Supplemental disclosure of non-cash investing and financing activities: Accounts payable for property and equipment purchases Receivable for stock option exercises Notes to Financial Statements The Company and Significant Accounting Policies Basic and Diluted Net Income (Loss) Per Share Share-Based Compensation and Stockholders' Equity Comprehensive Income (loss) Fair Value Measurements and Marketable Securities Agreements Income Taxes Related Party Transaction Therapeutic Discovery Project Tax Credit Recent Accounting Pronouncements Assets, Current Assets Liabilities, Current Liabilities Development Stage Enterprise, Deficit Accumulated During Development Stage Stockholders' Equity Attributable to Parent Liabilities and Equity Revenues Operating Expenses Operating Income (Loss) Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Weighted Average Number of Shares Outstanding, Basic Weighted Average Number of Shares Outstanding, Diluted Increase (Decrease) in Accounts Receivable Increase (Decrease) in Accounts Payable Increase (Decrease) in Accrued Liabilities IncreaseDecreaseInDeferredRent Net Cash Provided by (Used in) Operating Activities Payments to Acquire Property, Plant, and Equipment Payments for (Proceeds from) Removal Costs Payments to Acquire Available-for-sale Securities Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Financing Activities The increase (decrease) during the reporting period in the amount of the cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively. [From Standard Element (instant) - Amounts due from owners or affiliates of the reporting entity related to issuance of the entity's capital stock before cash payment is received (does not include amounts due from officers or directors). This element would also include the receivable for proceeds from the issuance of shares under employee stock option exercises which proceeds have not been received as of the reporting date due to the timing of the transaction date versus the settlement date.] The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Also Tabular disclosure of marketable securities. This may consist of investments in certain debt and equity securities, short-term investments and other assets. The entire disclosure for significant arrangements with third parties, which includes arrangements in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services. The entire disclosure for the Therapeutic Discovery Project Tax Credit, which includes amount awarded and timing and accounting treatment of the award.