Organization and Basis of Presentation (Policy)	6 Months Ended
Organization and Basis of Presentation (Policy)	Jul. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Fiscal Year	Fiscal Year The Company reports results on the basis of 52 and 53 week periods and ends its fiscal year on the last Sunday in January. The other quarters generally end on the last Sunday of April, July and October. All quarters consist of 13 weeks except for one 14-week period in the fourth quarter of 53-week years. The second quarter of fiscal years 2018 and 2017 each consisted of 13 weeks.
Principles of Consolidation	Principles of Consolidation The accompanying interim unaudited consolidated financial statements have been prepared by the Company, in accordance with accounting principles generally accepted in the United States ("GAAP") and on the same basis as the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended January 29, 2017. In the opinion of the Company, these interim unaudited consolidated financial statements contain all adjustments (consisting of normal recurring adjustments) necessary to present fairly, in all material respects, the financial position of the Company for the interim periods presented. All intercompany balances have been eliminated. Certain information and footnote disclosures normally included in annual consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. Because the interim unaudited consolidated financial statements do not include all of the information and notes required by GAAP for a complete set of consolidated financial statements, they should be read in conjunction with the audited consolidated financial statements and notes included in the Company's Annual Report on Form 10-K for the year ended January 29, 2017. The results reported in these interim unaudited consolidated financial statements should not be regarded as indicative of results that may be expected for any subsequent period or for the entire year. The Company’s interim unaudited consolidated statements of income are referred to herein as the "Statements of Income." The Company’s interim unaudited consolidated balance sheets are referred to herein as the "Balance Sheets" and interim unaudited consolidated statements of cash flows as the "Statements of Cash Flows.
Segment Information	Segment Information The Company’s Chief Executive Officer ("CEO") has been identified as the Chief Operating Decision Maker ("CODM") as defined by guidance regarding segment disclosures (see Note 14 for further discussion). In fiscal year 2016, the Company identified five operating segments in total. Four of the operating segments aggregated into one reportable segment, the Semiconductor Products Group. The remaining operating segment, the Systems Innovation Group (shown as "All others"), could not be aggregated with the other operating segments and did not meet the criteria for a separate reportable segment as defined by the guidance regarding segment disclosure. As a result, the financial activity associated with the Systems Innovation Group was reported separately from the Company’s Semiconductor Products Group. This separate reporting was included in the "All others" category. On August 5, 2016, the Company completed its divestiture of its Snowbush Intellectual Property ("Snowbush IP") business (previously part of the Company’s Systems Innovation Group) to Rambus Inc. ("Rambus") for a purchase price of $32.0 million in cash along with the opportunity to receive additional payments from Rambus through 2022 based upon a percentage of sales by Rambus of new products expected to be developed by Rambus from the disposed assets. Therefore, as of January 29, 2017, the Company no longer has a Systems Innovation Group or an "All others" category The Company’s CEO functions as the CODM. The Company’s CODM makes operating decisions and assesses performance based on these operating segments. The four operating segments: Protection Products Group, Power and High-Reliability Products Group, Signal Integrity Products Group, and Wireless and Sensing Products Group, all have similar economic characteristics and have been aggregated into one reportable segment identified in the table below as the "Semiconductor Products Group".
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Adopted Accounting Guidance In the first quarter of fiscal year 2018, the Company adopted Financial Accounting Standards Board ("FASB") Accounting Standards Update ("ASU") No. 2016-09, Improvements to Employee Share-Based Payment Accounting (Topic 718). Under the amended guidance, all excess tax benefits and tax deficiencies will be recognized in the Statements of Income as they occur. This replaced the previous guidance, which required tax benefits that exceed compensation cost ("windfalls") to be recognized in additional paid in capital. It also eliminates the need to maintain a windfall pool, and removes the requirement to delay recognizing a windfall until it reduces current taxes payable. Using the modified retrospective adoption method, in the first quarter of fiscal year 2018, the Company recognized deferred tax assets of $8.4 million for the windfall tax benefits and also recognized an increase of an equal amount in the valuation allowance against those deferred tax assets. Under the amended guidance, companies can make an accounting policy election to either continue to estimate forfeitures or account for forfeitures as they occur. Upon adoption, the Company elected to account for forfeitures when they occur, on a modified retrospective basis. In the first quarter of fiscal year 2018, a cumulative effect adjustment of $2.0 million was recorded to retained earnings. The amended guidance also changed the Statements of Cash Flow presentation of excess tax benefits, classifying them as operating activities instead of financing activities, consistent with other cash flows related to income taxes. Further, following the adoption of this updated guidance, there will be additional dilutive effects in earnings per share calculations because excess tax benefits are no longer recognized in additional paid in capital. Due to the valuation allowance maintained against the Company’s deferred tax assets, the adoption of this updated guidance did not have a material impact on the Company’s consolidated financial statements. Accounting Guidance Issued but Not Adopted as of July 30, 2017 In July 2017, the FASB issued ASU No. 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815). This standard addresses narrow issues identified as a result of the complexity associated with applying GAAP for certain financial instruments with characteristics of liabilities and equity. Part I addresses the complexity of accounting for certain financial instruments with down round features. Part II addresses the difficulty of navigating Topic 480, Distinguishing Liabilities from Equity, because of the existence of pending content in the Accounting Standards Codification ("ASC") that results from the indefinite deferral of accounting requirements concerning mandatorily redeemable financial instruments of certain non-public entities and certain mandatorily redeemable non-controlling interests. The Company does not expect the adoption of this pronouncement to have a material impact on the Company’s consolidated financial statements. In March 2017, the FASB issued ASU No. 2017-07, Compensation - Retirement Benefits (Topic 715). This standard amends the Statements of Income presentation of the components of net periodic benefit cost for defined benefit pension and other post retirement plans. This standard requires companies to: (1) disaggregate the current service cost component from the other components of net periodic benefit cost (the "other components") and present it in the same line items on the Statements of Income as other current compensation costs for related employees and (2) present the other components outside of operating profit. This standard is required to be applied retrospectively and is effective for annual and interim periods beginning after December 15, 2017. The Company does not expect the adoption of this pronouncement to have a material impact on the Company’s consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350). The pronouncement was issued to simplify the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. This pronouncement stipulates that an entity should perform a goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount, and will recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value, with the loss recognized not exceeding the total amount of goodwill allocated to that reporting unit. The amendments in this pronouncement are to be applied on a prospective basis. This guidance will be effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, with early adoption permitted for interim or annual goodwill impairment tests performed on testing dates after January 31, 2017. The adoption of this pronouncement is not expected to have a material impact on the Company’s consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805). This standard clarifies the definition of a business to assist entities with evaluating when a set of assets acquired or disposed of should be considered a business. The new standard requires an entity to evaluate if substantially all the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar identifiable assets; if so, the set would not be considered a business. The new standard also requires a business to include at least one substantive process and narrows the definition of outputs. The new standard is effective for interim and annual periods beginning after December 15, 2017, and may be adopted earlier. The standard would be applied prospectively to any transaction occurring on or after the adoption date. The impact of this standard will be dependent upon the specific facts and circumstances of any applicable future acquisitions or dispositions. In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Asset Transfers Other Than Inventory (Topic 740). This accounting standard update is aimed at recognizing the income tax consequences of intra-entity transfers of assets other than inventory when they occur. This removes the exception to postpone recognition until the asset has been sold to an outside party. This ASU will be effective in the first quarter of fiscal year 2020. The standard update is required to be applied on a modified retrospective basis through a cumulative-effect adjustment to the Balance Sheet as of the beginning of the fiscal year of adoption. The Company is currently assessing the impact this pronouncement will have on its consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments (Topic 230). The primary purpose of this ASU is to reduce the diversity in practice that has resulted from the lack of consistent principles on this topic. This ASU is effective for fiscal years beginning after December 15, 2017. This ASU will be effective for the Company as of the beginning of fiscal year 2019. Early adoption is permitted in any interim or annual period. The Company is continuing to assess the overall impacts of the new standard. The Company does not expect the adoption of this pronouncement to have a material impact on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which will require that substantially all leases be recognized by lessees on their Balance Sheets as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. The new standard also will result in enhanced quantitative and qualitative disclosures, including descriptions of significant judgments made by management, to provide greater insight into the extent of expense recognized and expected to be recognized from existing leases. The standard requires modified retrospective adoption and will be effective for the Company as of the beginning of fiscal year 2020. The Company expects the valuation of right of use assets and lease liabilities, previously described as operating leases, to be the present value of the Company's forecasted future lease commitments. The Company is continuing to assess the overall impacts of the new standard, including the discount rate to be applied in these valuations. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which will require an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance addresses, in particular, contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. Public entities are required to apply the amendments on either a full- or modified-retrospective basis for annual periods beginning after December 15, 2017 and for interim periods within those annual periods. This update will be effective for the Company beginning in the first quarter of fiscal year 2019. The Company plans to adopt the standard retrospectively with the cumulative effect of initially applying it recognized at the date of initial application ("modified retrospective" approach). The Company’s assessment has identified a change in revenue recognition timing on the Company's component sales made to certain distributors where revenues are currently deferred and not recognized until the distributor sells the components to the distributor’s customers. The Company expects to recognize revenue when the Company delivers or "sells into" the distributor rather than deferring recognition until the distributor sells the components or "sells through" to the end customer. On the date of initial application, the Company will remove the deferred net revenue on component sales made to certain distributors through a cumulative adjustment to retained earnings. The Company expects the revenue deferral to be offset by the acceleration of revenue recognition as control of the product transfers to its customer. As the Company continues its assessment, it is also identifying and preparing to implement changes to accounting policies, business processes and internal controls to support the new accounting and disclosure requirements.
Earnings Per Share	Basic earnings per common share is computed by dividing income available to common stockholders by the weighted-average number of shares of common stock outstanding during the reporting period. Diluted earnings per common share incorporates the incremental shares issuable, calculated using the treasury stock method, upon the assumed exercise of non-qualified stock options, the vesting of restricted stock units and performance unit awards if the conditions have been met.
Fair Value of Financial Instruments	Instruments Not Recorded at Fair Value on a Recurring Basis Some of the Company’s financial instruments are not measured at fair value on a recurring basis but are recorded at amounts that approximate fair value due to their liquid or short-term nature. Such financial assets and financial liabilities include: cash and cash equivalents, net receivables, certain other assets, accounts payable, accrued expenses, accrued personnel costs, and other current liabilities. The Company’s long-term debt is not recorded at fair value on a recurring basis, but is measured at fair value for disclosure purposes. As of July 30, 2017 and January 29, 2017, the Company had not elected the fair value option for any financial assets and liabilities for which such an election would have been permitted. The fair values of the foreign exchange forward contracts are valued using Level 2 inputs. Foreign currency forward contracts are valued using readily available foreign currency forward and interest rate curves. The fair value of each contract is determined by comparing the contract rate to the forward rate and discounting to the present value. Contracts in a gain position are recorded in the Balance Sheets under the caption "Other current assets" and the value of contracts in a loss position are recorded under the caption "Accrued liabilities" within the Balance Sheets. Please see Note 17 for further discussion of the Company’s derivative instruments. The convertible debt is valued using probability weighted cash flows (Level 3 inputs). The Triune Earn-out liability is valued utilizing estimates of annual revenue and operating income (Level 3 inputs) during a period ending January 2018. These estimates represent inputs for which market data are not available and are developed using the best information available about the assumptions that market participants would use when pricing the liability. The Cycleo Earn-out liability (see Note 12) is valued utilizing estimates of annual revenue and operating income (Level 3 inputs) through April 2020. These estimates represent inputs for which market data are not available and are developed using the best information available about the assumptions that market participants would use when pricing the liability. The AptoVision Earn-out liability is valued utilizing estimates of annual revenue, adjusted earnings and product development targets (Level 3 inputs) through July 2020. These estimates represent inputs for which market data are not available and are developed using the best information available about the assumptions that market participants would use when pricing the liability. The Company measures contingent earn-out liabilities at fair value on a recurring basis using significant unobservable inputs classified within Level 3 of the fair value hierarchy. The Company uses a Monte Carlo valuation method as a valuation technique to determine the value of the earn-out liability. The significant unobservable inputs used in the fair value measurements are revenue projections over the earn-out period, and the probability outcome percentages assigned to each scenario. Significant increases or decreases to either of these inputs in isolation would result in a significantly higher or lower liability, with a higher liability capped by the contractual maximum of the contingent earn-out obligation. Ultimately, the liabilities will be equivalent to the amount paid, and the difference between the fair value estimate and amount paid will be recorded in earnings. For the Triune Earn-out, Cycleo Earn-out and AptoVision Earn-out, these companies have business profiles comparable to a start-up company. Accordingly, their respective revenue projections are subject to significant revisions. This characteristic can result in volatile changes to the measurement of fair value for a given earn-out. The Company reviews and re-assesses the estimated fair value of contingent consideration on a quarterly basis, and the updated fair value could differ materially from the previous estimates. Changes in the estimated fair value of the Company’s contingent earn-out liabilities related to the time component of the present value calculation are reported in "Interest expense" within the Statements of Income. Adjustments to the estimated fair value related to changes in all other unobservable inputs are reported in operating income. Assets and Liabilities Recorded at Fair Value on a Non-Recurring Basis The Company reduces the carrying amounts of its goodwill, intangible assets, long-lived assets and non-marketable equity securities to fair value when held for sale or determined to be impaired.
Inventory	Inventories, consisting of material, material overhead, labor, and manufacturing overhead, are stated at the lower of cost (first-in, first-out) or market
Income Tax Uncertainties	The Company uses a two-step approach to recognize and measure uncertain tax positions ("UTP"). The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement.
Interest and Penalties on Unrecognized Tax Benefits	The Company’s policy is to include net interest and penalties related to unrecognized tax benefits within the provision for taxes within the Statements of Income.
Commitments and Contingencies	In accordance with accounting standards regarding loss contingencies, the Company accrues an undiscounted liability for those contingencies where the incurrence of a loss is probable and the amount can be reasonably estimated. The Company also discloses the amount accrued and the amount of a reasonably possible loss in excess of the amount accrued, if such disclosure is necessary for its consolidated financial statements not to be misleading. The Company does not record liabilities when the likelihood that the liability has been incurred is probable but the amount cannot be reasonably estimated, or when the liability is believed to be only reasonably possible or remote. The Company evaluates, at least quarterly, developments in its legal matters that could affect the amount of liability that has been previously accrued, and makes adjustments as appropriate. Significant judgment is required to determine both probability and the estimated amount. The Company may be unable to estimate a possible loss or range of possible loss due to various reasons, including, among others: (i) if the damages sought are indeterminate; (ii) if the proceedings are in early stages, (iii) if there is uncertainty as to the outcome of pending appeals, motions or settlements, (iv) if there are significant factual issues to be determined or resolved, and (v) if there are novel or unsettled legal theories presented. In such instances, there is considerable uncertainty regarding the ultimate resolution of such matters, including a possible eventual loss, if any. Because the outcomes of litigation and other legal matters are inherently unpredictable, the Company’s evaluation of legal matters or proceedings often involves a series of complex assessments by management about future events and can rely heavily on estimates and assumptions. While the consequences of certain unresolved matters and proceedings are not presently determinable, and an estimate of the probable and reasonably possible loss or range of loss in excess of amounts accrued for such proceedings cannot be reasonably made, an adverse outcome from such proceedings could have a material adverse effect on the Company’s earnings in any given reporting period. However, in the opinion of management, after consulting with legal counsel, any ultimate liability related to current outstanding claims and lawsuits, individually or in the aggregate, is not expected to have a material adverse effect on the Company’s consolidated financial statements, as a whole. However, legal matters are inherently unpredictable and subject to significant uncertainties, some of which are beyond the Company’s control. As such, even though the Company intends to vigorously defend itself with respect to its legal matters, there can be no assurance that the final outcome of these matters will not materially and adversely affect the Company’s business, financial condition, operating results, or cash flows.
Product Warranties	The Company’s general warranty policy provides for repair or replacement of defective parts. In some cases, a refund of the purchase price is offered. In certain instances the Company has agreed to other or additional warranty terms, including indemnification provisions.
Derivatives	These contracts met the criteria for cash flow hedges and the unrealized gains or losses, after tax, are recorded as a component of accumulated other comprehensive gain in shareholders’ equity. The effective portions of cash flow hedges are recorded in accumulated other comprehensive income ("AOCI") until the hedged item is recognized in selling, general and administrative ("SG&A") expense within the Statements of Income when the underlying hedged expense is recognized. Any ineffective portions of cash flow hedges are recorded in "Non-operating expense, net" within the Company’s Statements of Income. The Company presents its derivative assets and liabilities at their gross fair values on the Balance Sheets. The Company’s accounting treatment for these instruments is based on whether or not the instruments are designated as a hedging instrument. The Company is currently applying hedge accounting to all foreign currency derivatives and has designated these hedges as cash flow hedges.