Contingencies	12 Months Ended
Jan. 02, 2016
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Contingencies Legal Matters On or about January 29, 2015, Silicon Image, members of its Board, the Company and the Company’s wholly-owned merger acquisition subsidiary were named as defendants in two complaints filed in Santa Clara Superior Court by alleged stockholders of Silicon Image in connection with the proposed merger of Silicon Image and the Company. Both complaints were dated January 29, 2015 and were captioned respectively Molland v. George, et al. and Stein v. Silicon Image, Inc. et. al. Five additional complaints were subsequently filed on January 30, 2015, February 4, 2015 and February 9, 2015 in Delaware Chancery Court by alleged stockholders of Silicon Image, Inc. in connection with the Merger, captioned respectively Pfeiffer v. Martino et. al.; Lipinski v. Silicon Image, Inc. et. al.; Feldbaum et. al. v. Silicon Image, Inc. et. al; Nelson v. Silicon Image, Inc. et. al. and Partansky v. Silicon Image, Inc. et. al. The five Delaware matters were subsequently consolidated into an action captioned In re Silicon Image Stockholders Litigation by order of the Delaware Chancery Court on February 11, 2015, and a consolidated amended complaint was filed in the matter on February 13, 2015. Two complaints captioned Tapia v. Silicon Image, Inc. et. al. and Caldwel v. Silicon Image, Inc. were also filed on February 4, 2015 and February 9, 2015 in Santa Clara Superior Court by alleged stockholders in connection with the merger. Amended complaints were filed in the Molland and Stein actions on February 11, 2015. Each of these lawsuits were purported class actions brought on behalf of Silicon Image stockholders, asserting claims against each member of the Silicon Image Board for breach of fiduciary duty, and against various officers of the Silicon Image, the Company, and the Company’s wholly-owned merger subsidiary for aiding and abetting breach of fiduciary duty. The lawsuits alleged that the Merger did not appropriately value Silicon Image, was the result of an inadequate process, and included preclusive deal devices. The amended complaints also asserted that the Silicon Image’s disclosures regarding the Merger in its Schedule 14D-9 omitted material information regarding the Merger. Each of these complaints purported to seek unspecified damages. The Delaware cases have been settled and this settlement has been approved by the court. The settlement did not have a material adverse effect on our financial position. The California cases were dismissed with prejudice on February 29, 2019. In November 2014, a patent infringement lawsuit was filed by Papst Licensing GmbH & Co., KG ("Papst") against us in the U.S. District Court for the District of Delaware. On September 21, 2015, the parties entered into a settlement agreement. Under that agreement, we received a non-exclusive, irrevocable, fully paid up, perpetual, worldwide license for use of the asserted patents. The license fully exhausts and includes all claims of the asserted patents. The settlement did not have a material adverse effect on our financial position. On October 22, 2015, the case was dismissed with prejudice. In March 2014, the China National Development and Reform Commission ("NDRC") notified HDMI Licensing, LLC ("HDMI LLC"), a wholly-owned subsidiary of the Company and the agent for an entity charged with administering the HDMI specification, that the NDRC was investigating HDMI LLC’s licensing activities in China under the Chinese Anti-Monopoly Law ("AML"). The NDRC has available a broad range of remedies with respect to business practices it deems to violate the AML, including the ability to issue an order to cease conduct deemed illegal, confiscate gains deemed illegally obtained, impose a fine and require modifications to business practices. In July 2015, the NDRC concluded its investigation and informed HDMI LLC that it did not intend to impose monetary penalties on HDMI LLC, subject to HDMI LLC entering into a settlement agreement with the China Video Industry Association (“CVIA”) relating to various issues arising in connection with HDMI LLC licensing to Chinese companies. HDMI LLC is negotiating the specific implementation terms of this agreement with CVIA. Lattice cannot predict the outcome of this matter because administrative proceedings and negotiations with industry associations are inherently uncertain. At this stage of the proceedings, we do not have an estimate of the likelihood or the amount of any financial consequences to the Company. In January 2016 the Company commenced a suit against Technicolor SA and its affiliates in the United States District Court for the Northern District of California alleging that Technicolor had infringed certain patents relating to the HDMI specification. Technicolor has informed the Company that it will attempt to raise as a counterclaim a claim for payment to Technicolor and other HDMI founders their respective share of any HDMI adopters’ fees not used by Lattice and its predecessor in interest Silicon Image in the marketing and other activities in furtherance of the HDMI standard. Technicolor previously has indicated its belief that the HDMI founders enjoy a right to these funds but has never pursued such claims. At this stage of the proceedings, we do not have an estimate of the likelihood or the amount of any financial consequences to the Company. We are exposed to certain other asserted and unasserted potential claims. There can be no assurance that, with respect to potential claims made against us, we could resolve such claims under terms and conditions that would not have a material adverse effect on our business, our liquidity or our financial results. Periodically, we review the status of each significant 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, we then accrue a liability for the estimated loss based on the provisions of FASB ASC 450, “Contingencies" (“ASC 450”). 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, we reassess the potential liability related to pending claims and litigation and may revise estimates.

Contingencies

Legal Matters

On or about January 29, 2015, Silicon Image, members of its Board, the Company and the Company’s wholly-owned merger acquisition subsidiary were named as defendants in two complaints filed in Santa Clara Superior Court by alleged stockholders of Silicon Image in connection with the proposed merger of Silicon Image and the Company. Both complaints were dated January 29, 2015 and were captioned respectively Molland v. George, et al. and Stein v. Silicon Image, Inc. et. al. Five additional complaints were subsequently filed on January 30, 2015, February 4, 2015 and February 9, 2015 in Delaware Chancery Court by alleged stockholders of Silicon Image, Inc. in connection with the Merger, captioned respectively Pfeiffer v. Martino et. al.; Lipinski v. Silicon Image, Inc. et. al.; Feldbaum et. al. v. Silicon Image, Inc. et. al; Nelson v. Silicon Image, Inc. et. al. and Partansky v. Silicon Image, Inc. et. al. The five Delaware matters were subsequently consolidated into an action captioned In re Silicon Image Stockholders Litigation by order of the Delaware Chancery Court on February 11, 2015, and a consolidated amended complaint was filed in the matter on February 13, 2015. Two complaints captioned Tapia v. Silicon Image, Inc. et. al. and Caldwel v. Silicon Image, Inc. were also filed on February 4, 2015 and February 9, 2015 in Santa Clara Superior Court by alleged stockholders in connection with the merger. Amended complaints were filed in the Molland and Stein actions on February 11, 2015. Each of these lawsuits were purported class actions brought on behalf of Silicon Image stockholders, asserting claims against each member of the Silicon Image Board for breach of fiduciary duty, and against various officers of the Silicon Image, the Company, and the Company’s wholly-owned merger subsidiary for aiding and abetting breach of fiduciary duty. The lawsuits alleged that the Merger did not appropriately value Silicon Image, was the result of an inadequate process, and included preclusive deal devices. The amended complaints also asserted that the Silicon Image’s disclosures regarding the Merger in its Schedule 14D-9 omitted material information regarding the Merger. Each of these complaints purported to seek unspecified damages. The Delaware cases have been settled and this settlement has been approved by the court. The settlement did not have a material adverse effect on our financial position. The California cases were dismissed with prejudice on February 29, 2019.

In November 2014, a patent infringement lawsuit was filed by Papst Licensing GmbH & Co., KG ("Papst") against us in the U.S. District Court for the District of Delaware. On September 21, 2015, the parties entered into a settlement agreement. Under that agreement, we received a non-exclusive, irrevocable, fully paid up, perpetual, worldwide license for use of the asserted patents. The license fully exhausts and includes all claims of the asserted patents. The settlement did not have a material adverse effect on our financial position. On October 22, 2015, the case was dismissed with prejudice.

In March 2014, the China National Development and Reform Commission ("NDRC") notified HDMI Licensing, LLC ("HDMI LLC"), a wholly-owned subsidiary of the Company and the agent for an entity charged with administering the HDMI specification, that the NDRC was investigating HDMI LLC’s licensing activities in China under the Chinese Anti-Monopoly Law ("AML"). The NDRC has available a broad range of remedies with respect to business practices it deems to violate the AML, including the ability to issue an order to cease conduct deemed illegal, confiscate gains deemed illegally obtained, impose a fine and require modifications to business practices. In July 2015, the NDRC concluded its investigation and informed HDMI LLC that it did not intend to impose monetary penalties on HDMI LLC, subject to HDMI LLC entering into a settlement agreement with the China Video Industry Association (“CVIA”) relating to various issues arising in connection with HDMI LLC licensing to Chinese companies. HDMI LLC is negotiating the specific implementation terms of this agreement with CVIA. Lattice cannot predict the outcome of this matter because administrative proceedings and negotiations with industry associations are inherently uncertain. At this stage of the proceedings, we do not have an estimate of the likelihood or the amount of any financial consequences to the Company.

In January 2016 the Company commenced a suit against Technicolor SA and its affiliates in the United States District Court for the Northern District of California alleging that Technicolor had infringed certain patents relating to the HDMI specification. Technicolor has informed the Company that it will attempt to raise as a counterclaim a claim for payment to Technicolor and other HDMI founders their respective share of any HDMI adopters’ fees not used by Lattice and its predecessor in interest Silicon Image in the marketing and other activities in furtherance of the HDMI standard. Technicolor previously has indicated its belief that the HDMI founders enjoy a right to these funds but has never pursued such claims. At this stage of the proceedings, we do not have an estimate of the likelihood or the amount of any financial consequences to the Company.

We are exposed to certain other asserted and unasserted potential claims. There can be no assurance that, with respect to potential claims made against us, we could resolve such claims under terms and conditions that would not have a material adverse effect on our business, our liquidity or our financial results. Periodically, we review the status of each significant 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, we then accrue a liability for the estimated loss based on the provisions of FASB ASC 450, “Contingencies" (“ASC 450”). 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, we reassess the potential liability related to pending claims and litigation and may revise estimates.