Income Taxes	3 Months Ended
Mar. 31, 2013
Income Tax Disclosure [Abstract]
Income Taxes	6. Income Taxes For the three months ended March 31, 2013 and 2012, the Company recorded an income tax benefit of $2,182 and $561, respectively. Income tax is related to federal, state, and to a lesser extent, foreign tax obligations. The Company’s effective tax rate may vary from period to period based on changes in estimated taxable income or loss, changes to federal, state or foreign tax laws, deductibility of certain costs and expenses, and as a result of acquisitions. The Company’s estimated effective tax rate for 2013, which has been applied to the Company’s loss before income taxes for the three months ended March 31, 2013, varies from the statutory rate primarily due to 2013 federal and state research and development credits that decrease the effective tax rate, partially offset by non-deductible stock-based compensation expense, that increases the effective tax rate. Additionally, for the three months ended March 31, 2013, the income tax benefit was increased by the 2012 federal research and development credit which was treated as a discrete item. The American Taxpayer Relief Act of 2012, (the “Act”), was enacted on January 2, 2013. The Act retroactively reinstated the federal research and development credit from January 1, 2012. The effect of the change in the tax law related to 2012 was $1,324, which was recognized as a benefit to income tax expense in the first quarter of 2013, the quarter in which the law was enacted. For 2012, the Company’s estimated effective tax rate varied from the statutory tax rate primarily due to non-deductible stock-based compensation expense that increased the effective tax rate partially offset by state research and development credits that decreased the effective tax rate. Additionally, for the three months ended March 31, 2012, the income tax benefit was increased by the recognition for tax purposes of stock based compensation expense on disqualifying dispositions of incentive stock options that occurred during the period which was treated as a discrete item. The Company had net deferred tax assets of $11,985 at December 31, 2012, which increased to $14,179 at March 31, 2013, primarily as a result of the income tax benefit recorded for the three months ended March 31, 2013. The Company has not recorded any amounts for unrecognized tax benefits as of March 31, 2013 or December 31, 2012. As of March 31, 2013 and December 31, 2012, the Company had no accrued interest or tax penalties recorded.

Income Taxes

3 Months Ended

Mar. 31, 2013

6. Income Taxes

For the three months ended March 31, 2013 and 2012, the Company recorded an income tax benefit of $2,182 and $561, respectively. Income tax is related to federal, state, and to a lesser extent, foreign tax obligations.

The Company’s effective tax rate may vary from period to period based on changes in estimated taxable income or loss, changes to federal, state or foreign tax laws, deductibility of certain costs and expenses, and as a result of acquisitions. The Company’s estimated effective tax rate for 2013, which has been applied to the Company’s loss before income taxes for the three months ended March 31, 2013, varies from the statutory rate primarily due to 2013 federal and state research and development credits that decrease the effective tax rate, partially offset by non-deductible stock-based compensation expense, that increases the effective tax rate. Additionally, for the three months ended March 31, 2013, the income tax benefit was increased by the 2012 federal research and development credit which was treated as a discrete item. The American Taxpayer Relief Act of 2012, (the “Act”), was enacted on January 2, 2013. The Act retroactively reinstated the federal research and development credit from January 1, 2012. The effect of the change in the tax law related to 2012 was $1,324, which was recognized as a benefit to income tax expense in the first quarter of 2013, the quarter in which the law was enacted.

For 2012, the Company’s estimated effective tax rate varied from the statutory tax rate primarily due to non-deductible stock-based compensation expense that increased the effective tax rate partially offset by state research and development credits that decreased the effective tax rate. Additionally, for the three months ended March 31, 2012, the income tax benefit was increased by the recognition for tax purposes of stock based compensation expense on disqualifying dispositions of incentive stock options that occurred during the period which was treated as a discrete item.

The Company had net deferred tax assets of $11,985 at December 31, 2012, which increased to $14,179 at March 31, 2013, primarily as a result of the income tax benefit recorded for the three months ended March 31, 2013.

The Company has not recorded any amounts for unrecognized tax benefits as of March 31, 2013 or December 31, 2012. As of March 31, 2013 and December 31, 2012, the Company had no accrued interest or tax penalties recorded.