Income Taxes	9 Months Ended
Sep. 25, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We file income tax returns with the IRS and in various U.S. states and foreign jurisdictions. On December 8, 2011 and January 23, 2012, the IRS issued Statutory Notices of Deficiency (the “Notices”) determining, respectively, additional taxes for 2002 through 2004 of $19.8 million and additional taxes for 2005 through 2007 of $21.4 million, excluding interest. The IRS’s determinations relate primarily to inter-company transactions, computational adjustments to the R&D credit and reductions to the benefits of tax credit carry backs and carry forwards. We deposited $18.0 million as a cash bond with the IRS in 2008, and converted this amount to tax payments in March 2012. On March 6, 2012 and April 20, 2012, we filed petitions challenging the Notices in the U.S. Tax Court. The petitions request redetermination of the deficiencies produced by the IRS’s adjustments. The IRS filed responses to our petitions, in which the IRS conceded the R&D credit adjustment for 2004. The Tax Court consolidated the two cases and a judge was assigned. The federal statute of limitations for the 2002 and 2003 tax years expired, and the ongoing Tax Court litigation concerns only the 2004 through 2007 years. On January 31, 2013, the IRS conceded one of the adjustments at issue in the litigation for the 2004 through 2007 tax years. The conceded adjustment related to certain inter-company services transactions. The concession only impacted our 2007 tax year. As a result of this concession, we recognized a tax and interest benefit of $6.8 million in 2013 due to the release of certain tax reserves. As part of the proceedings, Altera raised certain affirmative adjustments to its inter-company transactions. The parties filed a series of Joint Status Reports with the court addressing these affirmative adjustments. Altera and the IRS filed cross motions for partial summary judgment on the largest adjustment still at issue, which is related to the treatment of stock-based compensation in an inter-company cost-sharing transaction. As part of the partial motion for summary judgment process, both sides filed briefs on May 28, 2013, July 25, 2013 and September 9, 2013. The parties presented oral arguments on the stock-based compensation cost-sharing issue to the Tax Court on July 24, 2014. On July 27, 2015, the Tax Court issued an opinion accepting Altera's position and concluded that we are not liable for any tax or interest associated with the stock-based compensation cost-sharing issue. Altera is in the process of evaluating the implications of this opinion with respect to the 2004 through 2007 tax years and all subsequent impacted tax years. The Tax Court opinion will not be complete until the tax computation is finalized and entered into the Tax Court record. The Tax Court has granted the IRS an additional extension of time to submit their tax computation by November 12, 2015. Upon the finalization of the tax computation, the Tax Court opinion will be final, and the IRS will have a 90 day period to appeal. If the IRS appeals, it could take two to three years for the litigation to be resolved. We are currently unable to predict if the IRS will appeal the opinion and the outcome of any such appeal. Subsequent to the end of its quarter ended September 25, 2015, Altera and the IRS settled all other outstanding issues including affirmative adjustments before the Tax Court based upon a settlement entered into on September 29, 2015. As a result of the settlement of the affirmative adjustments, Altera expects an aggregate favorable impact of $40 to $50 million to net income in the fourth quarter of 2015 due to the reversal of previously established reserves for uncertain tax positions. The IRS is currently examining our 2010 and 2011 tax years. We believe we have made adequate tax payments or accrued adequate amounts for our tax liabilities for these years and that the outcome of the audit will not have a material adverse effect on our consolidated operating results or financial position. Other significant jurisdictions in which we are or may be subject to examination for fiscal years 2002 forward include China (including Hong Kong), Denmark, Ireland, Malaysia, Japan, Canada, United Kingdom and the state of California. We believe we have made adequate tax payments and/or accrued adequate amounts such that the outcome of these audits will have no material adverse effect on our consolidated operating results. Due to the potential resolution of various tax examinations, and the expiration of various statutes of limitations, it is possible that our gross unrecognized tax benefits may change within the next twelve months. However, given the number of years remaining subject to examination and the number of matters being examined, we are unable to estimate the full range of potential adjustments to the balance of gross unrecognized tax benefits. Our effective tax rate reflects the impact of a significant amount of our earnings being taxed in foreign jurisdictions at rates substantially below the U.S. statutory rate. Our effective tax rate for the three months ended September 25, 2015 was 21.4% compared with 12.7% for the three months ended September 26, 2014. The increase in our effective tax rate was primarily due to adverse geographic mix of earnings caused by the change in proportionately lower earnings in foreign jurisdictions taxed at rates below the U.S. statutory tax rate offset by higher one-time benefits in 2015 compared with the same period in 2014. During the three months ended September 25, 2015, we recognized a net benefit of $2.3 million related to the deductible portion of Merger-related expenses. In addition, we reversed $2.6 million of liabilities and related interest for uncertain tax positions upon the expiration of foreign statutes of limitations, and we recognized a net benefit of $1.1 million of true-up adjustments resulting from the filing of tax returns in domestic and foreign jurisdictions. During the three months ended September 26, 2014, we reversed $2.9 million of liabilities and related interest for uncertain tax positions upon the expiration of foreign and domestic statutes of limitations. Our effective tax rate for the nine months ended September 25, 2015 was 14.6% compared with 11.6% for the nine months ended September 26, 2014. The net change in our effective tax rate was primarily due to adverse geographic mix of earnings caused by the change in proportionately lower earnings in foreign jurisdictions taxed at rates below the U.S. statutory tax rate offset by higher one-time tax benefits in 2015 compared with the same period in 2014. During the nine months ended September 25, 2015, we recognized one-time benefits of $7.1 million related to foreign tax credits earned in excess of a foreign dividend and $6.5 million related to the deductible portion of merger-related expenses. In addition, we reversed $2.6 million of liabilities and related interest for uncertain tax positions upon expiration of foreign statutes of limitation. During the nine months ended September 26, 2014, we reversed $6.9 million of liabilities and the related interest for uncertain tax positions upon the expiration of a domestic and foreign statutes of limitations. As of September 25, 2015, we had total gross unrecognized tax benefits of $378.9 million which, if recognized, would potentially impact our effective tax rate. As of December 31, 2014, we had total gross unrecognized tax benefits of $341.1 million. We are unable to make a reasonable estimate as to if and when cash settlements with the relevant taxing authorities may occur. We recognize interest and penalties related to uncertain tax positions in our income tax provision. We have accrued approximately $51.1 million and $45.8 million for interest and penalties related to uncertain tax positions as of September 25, 2015 and December 31, 2014, respectively.

Income Taxes

We file income tax returns with the IRS and in various U.S. states and foreign jurisdictions. On December 8, 2011 and January 23, 2012, the IRS issued Statutory Notices of Deficiency (the “Notices”) determining, respectively, additional taxes for 2002 through 2004 of $19.8 million and additional taxes for 2005 through 2007 of $21.4 million, excluding interest. The IRS’s determinations relate primarily to inter-company transactions, computational adjustments to the R&D credit and reductions to the benefits of tax credit carry backs and carry forwards. We deposited $18.0 million as a cash bond with the IRS in 2008, and converted this amount to tax payments in March 2012. On March 6, 2012 and April 20, 2012, we filed petitions challenging the Notices in the U.S. Tax Court. The petitions request redetermination of the deficiencies produced by the IRS’s adjustments. The IRS filed responses to our petitions, in which the IRS conceded the R&D credit adjustment for 2004. The Tax Court consolidated the two cases and a judge was assigned. The federal statute of limitations for the 2002 and 2003 tax years expired, and the ongoing Tax Court litigation concerns only the 2004 through 2007 years.

On January 31, 2013, the IRS conceded one of the adjustments at issue in the litigation for the 2004 through 2007 tax years. The conceded adjustment related to certain inter-company services transactions. The concession only impacted our 2007 tax year. As a result of this concession, we recognized a tax and interest benefit of $6.8 million in 2013 due to the release of certain tax reserves. As part of the proceedings, Altera raised certain affirmative adjustments to its inter-company transactions. The parties filed a series of Joint Status Reports with the court addressing these affirmative adjustments. Altera and the IRS filed cross motions for partial summary judgment on the largest adjustment still at issue, which is related to the treatment of stock-based compensation in an inter-company cost-sharing transaction. As part of the partial motion for summary judgment process, both sides filed briefs on May 28, 2013, July 25, 2013 and September 9, 2013. The parties presented oral arguments on the stock-based compensation cost-sharing issue to the Tax Court on July 24, 2014.

On July 27, 2015, the Tax Court issued an opinion accepting Altera's position and concluded that we are not liable for any tax or interest associated with the stock-based compensation cost-sharing issue. Altera is in the process of evaluating the implications of this opinion with respect to the 2004 through 2007 tax years and all subsequent impacted tax years. The Tax Court opinion will not be complete until the tax computation is finalized and entered into the Tax Court record. The Tax Court has granted the IRS an additional extension of time to submit their tax computation by November 12, 2015. Upon the finalization of the tax computation, the Tax Court opinion will be final, and the IRS will have a 90 day period to appeal. If the IRS appeals, it could take two to three years for the litigation to be resolved. We are currently unable to predict if the IRS will appeal the opinion and the outcome of any such appeal.

Subsequent to the end of its quarter ended September 25, 2015, Altera and the IRS settled all other outstanding issues including affirmative adjustments before the Tax Court based upon a settlement entered into on September 29, 2015. As a result of the settlement of the affirmative adjustments, Altera expects an aggregate favorable impact of $40 to $50 million to net income in the fourth quarter of 2015 due to the reversal of previously established reserves for uncertain tax positions.

The IRS is currently examining our 2010 and 2011 tax years. We believe we have made adequate tax payments or accrued adequate amounts for our tax liabilities for these years and that the outcome of the audit will not have a material adverse effect on our consolidated operating results or financial position.

Other significant jurisdictions in which we are or may be subject to examination for fiscal years 2002 forward include China (including Hong Kong), Denmark, Ireland, Malaysia, Japan, Canada, United Kingdom and the state of California. We believe we have made adequate tax payments and/or accrued adequate amounts such that the outcome of these audits will have no material adverse effect on our consolidated operating results. Due to the potential resolution of various tax examinations, and the expiration of various statutes of limitations, it is possible that our gross unrecognized tax benefits may change within the next twelve months. However, given the number of years remaining subject to examination and the number of matters being examined, we are unable to estimate the full range of potential adjustments to the balance of gross unrecognized tax benefits.

Our effective tax rate reflects the impact of a significant amount of our earnings being taxed in foreign jurisdictions at rates substantially below the U.S. statutory rate. Our effective tax rate for the three months ended September 25, 2015 was 21.4% compared with 12.7% for the three months ended September 26, 2014. The increase in our effective tax rate was primarily due to adverse geographic mix of earnings caused by the change in proportionately lower earnings in foreign jurisdictions taxed at rates below the U.S. statutory tax rate offset by higher one-time benefits in 2015 compared with the same period in 2014. During the three months ended September 25, 2015, we recognized a net benefit of $2.3 million related to the deductible portion of Merger-related expenses. In addition, we reversed $2.6 million of liabilities and related interest for uncertain tax positions upon the expiration of foreign statutes of limitations, and we recognized a net benefit of $1.1 million of true-up adjustments resulting from the filing of tax returns in domestic and foreign jurisdictions. During the three months ended September 26, 2014, we reversed $2.9 million of liabilities and related interest for uncertain tax positions upon the expiration of foreign and domestic statutes of limitations.

Our effective tax rate for the nine months ended September 25, 2015 was 14.6% compared with 11.6% for the nine months ended September 26, 2014. The net change in our effective tax rate was primarily due to adverse geographic mix of earnings caused by the change in proportionately lower earnings in foreign jurisdictions taxed at rates below the U.S. statutory tax rate offset by higher one-time tax benefits in 2015 compared with the same period in 2014. During the nine months ended September 25, 2015, we recognized one-time benefits of $7.1 million related to foreign tax credits earned in excess of a foreign dividend and $6.5 million related to the deductible portion of merger-related expenses. In addition, we reversed $2.6 million of liabilities and related interest for uncertain tax positions upon expiration of foreign statutes of limitation. During the nine months ended September 26, 2014, we reversed $6.9 million of liabilities and the related interest for uncertain tax positions upon the expiration of a domestic and foreign statutes of limitations.

As of September 25, 2015, we had total gross unrecognized tax benefits of $378.9 million which, if recognized, would potentially impact our effective tax rate. As of December 31, 2014, we had total gross unrecognized tax benefits of $341.1 million. We are unable to make a reasonable estimate as to if and when cash settlements with the relevant taxing authorities may occur.

We recognize interest and penalties related to uncertain tax positions in our income tax provision. We have accrued approximately $51.1 million and $45.8 million for interest and penalties related to uncertain tax positions as of September 25, 2015 and December 31, 2014, respectively.