Contingencies	6 Months Ended
Sep. 28, 2013
Loss Contingency [Abstract]
Contingencies	Contingencies Patent Litigation On December 28, 2007, a patent infringement lawsuit was filed by PACT against the Company in the U.S. District Court for the Eastern District of Texas, Marshall Division (PACT XPP Technologies, AG. v. Xilinx, Inc. and Avnet, Inc. Case No. 2:07-CV-563). The lawsuit pertained to eleven different patents and PACT sought injunctive relief, damages including enhanced damages, interest and attorneys’ fees. Nine of the eleven patents were dismissed from the case prior to trial. Trial commenced in the matter on May 14, 2012 and on May 18, 2012 the jury concluded its deliberations. The jury found five claims of the two patents held by PACT were valid and were willfully infringed by the Company. The jury awarded PACT the sum of $15.4 million as damages and royalties on past Xilinx sales from March 2002 to May 2012. On August 30, 2013, a judge in the U.S. District Court for the Eastern District of Texas, Marshall Division, issued a memorandum order finding enhanced damages to be appropriate in the patent infringement suit brought against the Company. The judge’s order for enhanced damages adjusted the jury award to approximately $38.5 million on the basis of the judge’s consideration of applicable factors. On September 3, 2013, the court also issued an order requiring the Company to pay approximately $2.5 million for PACT’s costs and attorneys’ fees and an order requiring the Company to pay approximately $3.0 million for pre- and post-judgment interest. The court denied without prejudice PACT’s motion for ongoing royalties on Xilinx sales from May 2012 and onwards which are subject to the patents in suit, and ordered the parties to negotiate resolution of the future royalty rate on such Xilinx sales. Final judgment in the case was issued on September 4, 2013. As a result of the August 30, 2013 and September 3, 2013 orders, the Company recorded a charge of $28.6 million in the second quarter of fiscal year 2014. The Company is unable to estimate the possible range of loss regarding the ongoing and future royalties at this time. On October 2, 2013, the Company filed a Notice of Appeal with the U.S. District Court for the Eastern District of Texas, Marshall Division of its appeal to the U.S. Court of Appeals for the Federal Circuit. On February 14, 2011, the Company filed a complaint for declaratory judgment of patent non-infringement and invalidity against Intellectual Ventures in the U.S. District Court for the Northern District of California. On September 30, 2011, the Company amended its complaint in this case to eliminate certain defendants and patents from the action (Xilinx, Inc. v. Intellectual Ventures I LLC and Intellectual Ventures II LLC, Case No CV11-0671). The lawsuit pertains to one patent and seeks judgment of non-infringement by Xilinx and judgment that the patent is invalid and unenforceable, as well as costs and attorneys’ fees. On February 15, 2011, Intellectual Ventures added the Company as a defendant in its complaint for patent infringement previously filed against Altera, Microsemi and Lattice in the U.S. District Court for the District of Delaware (Intellectual Ventures I LLC and Intellectual Ventures II LLC v. Altera Corporation, Microsemi Corporation, Lattice Semiconductor Corporation and Xilinx, Inc., Case No. 10-CV-1065). The lawsuit pertains to five patents, four of which Xilinx is alleged to be infringing. Intellectual Ventures seeks unspecified damages, interest and attorneys’ fees and the proceedings are in their early stages. The Company is unable to estimate its range of possible loss in this matter at this time. On October 17, 2011, the Company filed a complaint for patent non-infringement and invalidity and violation of California Business and Professions Code Section 17200 in the U.S. District Court for the Northern District of California against Intellectual Ventures and related entities as well as additional defendants (Xilinx, Inc. v. Intellectual Ventures, LLC. Intellectual Ventures Management, LLC, Detelle Relay KG, LLC, Roldan Block NY LLC, Latrosse Technologies LLC, TR Technologies Foundation LLC, Taichi Holdings, LLC, Noregin Assets N.V., LLC and Intellectual Venture Funding LLC Case No CV-04407). By order dated January 25, 2012, the Court granted with leave to amend defendants' motion to dismiss the Company's claim for violation of California Business and Professions Code section 17200. The Company has amended its complaint to remove the claim for violation of California Business and Professions Code section 17200. The remainder of the lawsuit pertains to two patents and seeks judgments of non-infringement by the Company and judgments that the patents are invalid and unenforceable, as well as costs and attorneys’ fees. On May 30, 2012, a patent infringement lawsuit was filed by Semcon against the Company in the United States District Court for the District of Delaware (Semcon Tech, LLC v. Xilinx, Inc., Case No. 1:12-CV-00691). The lawsuit pertains to one patent and Semcon sought unspecified damages, costs and expenses. On August 5, 2013 the lawsuit was dismissed and the Company was indemnified by other parties involved in the action, therefore no payment was made by the Company in connection with the dismissal. On November 5, 2012, a patent infringement lawsuit was filed by Mosaid against the Company in the U.S. District Court for the Eastern District of Texas (Mosaid Technologies Inc. v. Xilinx, Inc., Case No. 6:12-CV-00847). The lawsuit pertains to five patents and Mosaid seeks unspecified damages, costs, fees, royalties and injunctive relief and the proceedings are in their early stages. The Company is unable to estimate its range of possible loss in this matter at this time. The Company intends to continue to protect and defend our IP vigorously. Other Matters Except as stated above, there are no pending legal proceedings of a material nature to which the Company is a party of which any of its property is the subject. From time to time, the Company is involved in various disputes and litigation matters that arise in the ordinary course of our business. These include disputes and lawsuits related to IP, mergers and acquisitions, licensing, contract law, tax, regulatory, distribution arrangements, employee relations and other matters. Periodically, the Company reviews the status of each matter and assess its potential financial exposure. If the potential loss from any claim or legal proceeding is considered probable and a range of possible losses can be estimated, the Company accrues a liability for the estimated loss. Legal proceedings are subject to uncertainties, and the outcomes are difficult to predict. Because of such uncertainties, accruals are based only on the best information available at the time. As additional information becomes available, the Company continues to reassess the potential liability related to pending claims and litigation and may revise estimates.

Contingencies

Patent Litigation

On December 28, 2007, a patent infringement lawsuit was filed by PACT against the Company in the U.S. District Court for the Eastern District of Texas, Marshall Division (PACT XPP Technologies, AG. v. Xilinx, Inc. and Avnet, Inc. Case No. 2:07-CV-563). The lawsuit pertained to eleven different patents and PACT sought injunctive relief, damages including enhanced damages, interest and attorneys’ fees. Nine of the eleven patents were dismissed from the case prior to trial. Trial commenced in the matter on May 14, 2012 and on May 18, 2012 the jury concluded its deliberations. The jury found five claims of the two patents held by PACT were valid and were willfully infringed by the Company. The jury awarded PACT the sum of $15.4 million as damages and royalties on past Xilinx sales from March 2002 to May 2012. On August 30, 2013, a judge in the U.S. District Court for the Eastern District of Texas, Marshall Division, issued a memorandum order finding enhanced damages to be appropriate in the patent infringement suit brought against the Company. The judge’s order for enhanced damages adjusted the jury award to approximately $38.5 million on the basis of the judge’s consideration of applicable factors. On September 3, 2013, the court also issued an order requiring the Company to pay approximately $2.5 million for PACT’s costs and attorneys’ fees and an order requiring the Company to pay approximately $3.0 million for pre- and post-judgment interest. The court denied without prejudice PACT’s motion for ongoing royalties on Xilinx sales from May 2012 and onwards which are subject to the patents in suit, and ordered the parties to negotiate resolution of the future royalty rate on such Xilinx sales. Final judgment in the case was issued on September 4, 2013.

As a result of the August 30, 2013 and September 3, 2013 orders, the Company recorded a charge of $28.6 million in the second quarter of fiscal year 2014. The Company is unable to estimate the possible range of loss regarding the ongoing and future royalties at this time. On October 2, 2013, the Company filed a Notice of Appeal with the U.S. District Court for the Eastern District of Texas, Marshall Division of its appeal to the U.S. Court of Appeals for the Federal Circuit.

On February 14, 2011, the Company filed a complaint for declaratory judgment of patent non-infringement and invalidity against Intellectual Ventures in the U.S. District Court for the Northern District of California. On September 30, 2011, the Company amended its complaint in this case to eliminate certain defendants and patents from the action (Xilinx, Inc. v. Intellectual Ventures I LLC and Intellectual Ventures II LLC, Case No CV11-0671). The lawsuit pertains to one patent and seeks judgment of non-infringement by Xilinx and judgment that the patent is invalid and unenforceable, as well as costs and attorneys’ fees.

On February 15, 2011, Intellectual Ventures added the Company as a defendant in its complaint for patent infringement previously filed against Altera, Microsemi and Lattice in the U.S. District Court for the District of Delaware (Intellectual Ventures I LLC and Intellectual Ventures II LLC v. Altera Corporation, Microsemi Corporation, Lattice Semiconductor Corporation and Xilinx, Inc., Case No. 10-CV-1065). The lawsuit pertains to five patents, four of which Xilinx is alleged to be infringing. Intellectual Ventures seeks unspecified damages, interest and attorneys’ fees and the proceedings are in their early stages. The Company is unable to estimate its range of possible loss in this matter at this time.

On October 17, 2011, the Company filed a complaint for patent non-infringement and invalidity and violation of California Business and Professions Code Section 17200 in the U.S. District Court for the Northern District of California against Intellectual Ventures and related entities as well as additional defendants (Xilinx, Inc. v. Intellectual Ventures, LLC. Intellectual Ventures Management, LLC, Detelle Relay KG, LLC, Roldan Block NY LLC, Latrosse Technologies LLC, TR Technologies Foundation LLC, Taichi Holdings, LLC, Noregin Assets N.V., LLC and Intellectual Venture Funding LLC Case No CV-04407). By order dated January 25, 2012, the Court granted with leave to amend defendants' motion to dismiss the Company's claim for violation of California Business and Professions Code section 17200. The Company has amended its complaint to remove the claim for violation of California Business and Professions Code section 17200. The remainder of the lawsuit pertains to two patents and seeks judgments of non-infringement by the Company and judgments that the patents are invalid and unenforceable, as well as costs and attorneys’ fees.

On May 30, 2012, a patent infringement lawsuit was filed by Semcon against the Company in the United States District Court for the District of Delaware (Semcon Tech, LLC v. Xilinx, Inc., Case No. 1:12-CV-00691). The lawsuit pertains to one patent and Semcon sought unspecified damages, costs and expenses. On August 5, 2013 the lawsuit was dismissed and the Company was indemnified by other parties involved in the action, therefore no payment was made by the Company in connection with the dismissal.

On November 5, 2012, a patent infringement lawsuit was filed by Mosaid against the Company in the U.S. District Court for the Eastern District of Texas (Mosaid Technologies Inc. v. Xilinx, Inc., Case No. 6:12-CV-00847). The lawsuit pertains to five patents and Mosaid seeks unspecified damages, costs, fees, royalties and injunctive relief and the proceedings are in their early stages. The Company is unable to estimate its range of possible loss in this matter at this time.

The Company intends to continue to protect and defend our IP vigorously.

Other Matters

Except as stated above, there are no pending legal proceedings of a material nature to which the Company is a party of which any of its property is the subject.

From time to time, the Company is involved in various disputes and litigation matters that arise in the ordinary course of our business. These include disputes and lawsuits related to IP, mergers and acquisitions, licensing, contract law, tax, regulatory, distribution arrangements, employee relations and other matters. Periodically, the Company reviews the status of each matter and assess its potential financial exposure. If the potential loss from any claim or legal proceeding is considered probable and a range of possible losses can be estimated, the Company accrues a liability for the estimated loss. Legal proceedings are subject to uncertainties, and the outcomes are difficult to predict. Because of such uncertainties, accruals are based only on the best information available at the time. As additional information becomes available, the Company continues to reassess the potential liability related to pending claims and litigation and may revise estimates.