Income Taxes	6 Months Ended
Jun. 30, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rates for the three months ended June 30, 2014 and 2013 were 39% and 37%, respectively. The effective tax rates for the six months ended June 30, 2014 and 2013 were 40% and 32%, respectively. The effective tax rates for the three and six months ended June 30, 2014 differed from the federal statutory rate primarily due to state taxes, foreign taxes and nondeductible expenses. The effective tax rates for the three and six months ended June 30, 2013 differed from the federal statutory rate primarily due to state taxes, foreign taxes and nondeductible expenses offset by a discrete benefit recorded for Federal R&D credit. On January 2, 2013, the American Taxpayer Relief Act of 2012 (H.R. 8) was signed into law which retroactively extended the Federal R&D credit from January 1, 2012 through December 31, 2013. As a result, the Company recognized the retroactive benefit of the 2012 Federal R&D credit of approximately $3.1 million as a discrete item in the first quarter of 2013, the period in which the legislation was enacted. The increase in our effective tax rates for the three months ended June 30, 2014 as compared to the three months ended June 30, 2013 was primarily attributable to the expiration of the Federal R&D tax credit on December 31, 2013. The increase in our effective tax rates for the six months ended June 30, 2014 as compared to the six months ended June 30, 2013 was primarily attributable to the expiration of the Federal R&D tax credit on December 31, 2013 and from the discrete item recorded in the first quarter of 2013 related to the retroactive benefit of the 2012 Federal R&D credit. Gross unrecognized tax benefits were $78.6 million and $68.2 million as of June 30, 2014 and December 31, 2013, respectively. The gross unrecognized tax benefits, if recognized by the Company, will result in a reduction of approximately $65.4 million to the provision for income taxes thereby favorably impacting the Company’s effective tax rate. The Company’s unrecognized tax benefits are classified as “Other non-current liabilities” on the Consolidated Balance Sheets. The Company includes interest and penalties related to unrecognized tax benefits within the "Provision for income taxes" on the Consolidated Statements of Operations. As of June 30, 2014, the total amount of gross interest and penalties accrued was $4.4 million, and is classified as “Other non-current liabilities” on the Consolidated Balance Sheets. Deferred tax assets include $19.0 million and $21.5 million classified as “Other current assets” and $100.9 million and $69.1 million classified as “Other non-current assets” on the Consolidated Balance Sheets as of June 30, 2014 and December 31, 2013, respectively. In evaluating its ability to realize the net deferred tax assets, the Company considered all available positive and negative evidence, including its past operating results and the forecast of future market growth, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies. As of June 30, 2014 and December 31, 2013, it was considered more likely than not that substantially all deferred tax assets would be realized, and no significant valuation allowance was recorded. Income tax benefits attributable to the exercise of employee stock options of $14.6 million and $20.2 million, during the three months ended June 30, 2014 and 2013, respectively, were recorded directly to "Additional paid-in capital" on the Consolidated Balance Sheets. Income tax benefits attributable to the exercise of employee stock options of $47.1 million and $31.5 million, during the six months ended June 30, 2014 and 2013, respectively, were recorded directly to "Additional paid-in capital" on the Consolidated Balance Sheets. The Company files U.S. federal, state and foreign tax returns. The Company is currently under examination by the IRS for the years 2008 through 2011. The IRS has completed its Field Exam of the 2008 and 2009 federal tax returns and has issued a Revenue Agent Report with a proposed assessment primarily related to the Company's R&D Credits claimed in those years. The Company has filed a protest against the proposed assessment and is currently in the midst of the IRS Appeals process. The IRS Field Exam of the 2010 and 2011 federal tax returns is in process. The 2012 federal tax return remains subject to examination by the IRS. The Company is also currently under examination by the state of California for the years 2006 and 2007. California has completed its Field Exam of the 2006 and 2007 California tax returns and has issued a Notice of Proposed Assessment primarily related to our R&D Credits claimed in those years. The Company has filed a protest against the proposed assessment and is currently awaiting the commencement of the Protest process with the Franchise Tax Board. The years 1997 through 2005, as well as 2008 through 2012, remain subject to examination by the state of California. The Company is currently not under examination in any foreign jurisdiction. The years 2011 through 2013 remain subject to examination by foreign jurisdictions. Given the potential outcome of the current examinations, as well as the impact of the current examination on the potential expiration of the statute of limitations, it is reasonably possible that the balance of unrecognized tax benefits could significantly change within the next twelve months. However, at this time, an estimate of the range of reasonably possible adjustments to the balance of unrecognized tax benefits cannot be made.

Income Taxes

The effective tax rates for the three months ended June 30, 2014 and 2013 were 39% and 37%, respectively. The effective tax rates for the six months ended June 30, 2014 and 2013 were 40% and 32%, respectively. The effective tax rates for the three and six months ended June 30, 2014 differed from the federal statutory rate primarily due to state taxes, foreign taxes and nondeductible expenses. The effective tax rates for the three and six months ended June 30, 2013 differed from the federal statutory rate primarily due to state taxes, foreign taxes and nondeductible expenses offset by a discrete benefit recorded for Federal R&D credit. On January 2, 2013, the American Taxpayer Relief Act of 2012 (H.R. 8) was signed into law which retroactively extended the Federal R&D credit from January 1, 2012 through December 31, 2013. As a result, the Company recognized the retroactive benefit of the 2012 Federal R&D credit of approximately $3.1 million as a discrete item in the first quarter of 2013, the period in which the legislation was enacted.

The increase in our effective tax rates for the three months ended June 30, 2014 as compared to the three months ended June 30, 2013 was primarily attributable to the expiration of the Federal R&D tax credit on December 31, 2013. The increase in our effective tax rates for the six months ended June 30, 2014 as compared to the six months ended June 30, 2013 was primarily attributable to the expiration of the Federal R&D tax credit on December 31, 2013 and from the discrete item recorded in the first quarter of 2013 related to the retroactive benefit of the 2012 Federal R&D credit.

Gross unrecognized tax benefits were $78.6 million and $68.2 million as of June 30, 2014 and December 31, 2013, respectively. The gross unrecognized tax benefits, if recognized by the Company, will result in a reduction of approximately $65.4 million to the provision for income taxes thereby favorably impacting the Company’s effective tax rate. The Company’s unrecognized tax benefits are classified as “Other non-current liabilities” on the Consolidated Balance Sheets. The Company includes interest and penalties related to unrecognized tax benefits within the "Provision for income taxes" on the Consolidated Statements of Operations. As of June 30, 2014, the total amount of gross interest and penalties accrued was $4.4 million, and is classified as “Other non-current liabilities” on the Consolidated Balance Sheets.

Deferred tax assets include $19.0 million and $21.5 million classified as “Other current assets” and $100.9 million and $69.1 million classified as “Other non-current assets” on the Consolidated Balance Sheets as of June 30, 2014 and December 31, 2013, respectively. In evaluating its ability to realize the net deferred tax assets, the Company considered all available positive and negative evidence, including its past operating results and the forecast of future market growth, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies. As of June 30, 2014 and December 31, 2013, it was considered more likely than not that substantially all deferred tax assets would be realized, and no significant valuation allowance was recorded.

Income tax benefits attributable to the exercise of employee stock options of $14.6 million and $20.2 million, during the three months ended June 30, 2014 and 2013, respectively, were recorded directly to "Additional paid-in capital" on the Consolidated Balance Sheets. Income tax benefits attributable to the exercise of employee stock options of $47.1 million and $31.5 million, during the six months ended June 30, 2014 and 2013, respectively, were recorded directly to "Additional paid-in capital" on the Consolidated Balance Sheets.

The Company files U.S. federal, state and foreign tax returns. The Company is currently under examination by the IRS for the years 2008 through 2011. The IRS has completed its Field Exam of the 2008 and 2009 federal tax returns and has issued a Revenue Agent Report with a proposed assessment primarily related to the Company's R&D Credits claimed in those years. The Company has filed a protest against the proposed assessment and is currently in the midst of the IRS Appeals process. The IRS Field Exam of the 2010 and 2011 federal tax returns is in process. The 2012 federal tax return remains subject to examination by the IRS.

The Company is also currently under examination by the state of California for the years 2006 and 2007. California has completed its Field Exam of the 2006 and 2007 California tax returns and has issued a Notice of Proposed Assessment primarily related to our R&D Credits claimed in those years. The Company has filed a protest against the proposed assessment and is currently awaiting the commencement of the Protest process with the Franchise Tax Board. The years 1997 through 2005, as well as 2008 through 2012, remain subject to examination by the state of California.

The Company is currently not under examination in any foreign jurisdiction. The years 2011 through 2013 remain subject to examination by foreign jurisdictions.

Given the potential outcome of the current examinations, as well as the impact of the current examination on the potential expiration of the statute of limitations, it is reasonably possible that the balance of unrecognized tax benefits could significantly change within the next twelve months. However, at this time, an estimate of the range of reasonably possible adjustments to the balance of unrecognized tax benefits cannot be made.