Impairment of Goodwill and Intangible Assets	12 Months Ended
Impairment of Goodwill and Intangible Assets	Jan. 02, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment of Goodwill and Intangible Assets	Impairment of Goodwill and Intangible Assets For fiscal 2015, the Impairment of goodwill and intangible assets is related to Qterics, Inc., which was acquired in the March 2015 acquisition of Silicon Image. During the fourth quarter of fiscal 2015, we determined that we experienced an impairment indicator related to the long-lived assets of the Qterics operating segment. For purposes of testing for impairment, the Company operates as two reporting units: the core Lattice ("Core") business, which includes intellectual property and semiconductor devices, and Qterics, a discrete software-as-a-service business unit in the Lattice legal entity structure. Although these two operating segments constitute two reportable segments, we combine Qterics with our Core business and report them together as one reportable segment due to the immaterial nature of the Qterics segment. Following this assessment, we concluded that goodwill and intangible assets has been impaired in the Qterics segment as of January 2, 2016. As a result we recorded an impairment charge amounting to $21.7 million, or approximately 92% of the previous value of goodwill and intangible assets, in the Consolidated Statements of Operations for the year ended January 2, 2016, comprising $12.7 million pertaining to goodwill, $3.9 million pertaining to developed technology, and $5.1 million pertaining to customer relationships. The valuation was based on the market approach and is our best estimate of fair value as of year end. No impairment charges were recorded for the Core segment in fiscal 2015, and we had no impairment charges in either fiscal 2014 or 2013.

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.