Description of Business and Summary of Significant Accounting Policies	3 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Summary of Significant Accounting Policies	Note 1. Description of Business and Summary of Significant Accounting Policies Description of Business Lumentum Holdings Inc. (“we,” “us,” “our,” “Lumentum” or the “Company”) is an industry-leading provider of optical and photonic products addressing a range of end market applications for manufacturing, inspection, and life-science applications. Our Cloud and Networking products include a wide range of components, modules, and subsystems to support customers including carrier networks for access (local), metro (intracity), long-haul (city-to-city and worldwide) and submarine (undersea) applications. Our products also address enterprise, cloud, and data center applications, including storage-access networks (“SANs”), local-area networks (“LANs”) and wide-area networks (“WANs”), as well as artificial intelligence and machine learning (“AI/ML”). Our Industrial Tech products include diode laser products such as VCSELs and edge emitting lasers. In the consumer end-market, our laser light sources are integrated into 3D sensing cameras which are used in applications in mobile devices, gaming, payment kiosks, computers, and other consumer electronics devices. Applications include biometric identification, computational photography, virtual and augmented reality, and natural user interfaces, among others. In the industrial end-market, our diode lasers are used primarily as pump sources for pulsed and kilowatt class fiber lasers. Our products also include laser products used in a variety of OEM applications including diode-pumped solid-state, fiber, diode, direct-diode and gas lasers such as argon-ion and helium-neon lasers. Basis of Presentation We have prepared the accompanying condensed consolidated financial statements in accordance with U.S. generally accepted accounting principles (“GAAP”), which requires management to make estimates and assumptions that affect the amounts reported in our condensed consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and various other assumptions believed to be reasonable. Although these estimates are based on management’s best knowledge of current events and actions that may impact us in the future, actual results may be different from the estimates. Our interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. In the opinion of the Company’s management, the information presented herein reflects all normal and recurring adjustments necessary for a fair presentation of our results of operations, financial position, stockholders’ equity, and cash flows. Our critical accounting policies are those that affect our financial statements materially and involve difficult, subjective, or complex judgments by management. Those policies are inventory valuation, revenue recognition, income taxes, goodwill, and business combinations. Prior to fiscal year 2024, we operated in two reportable segments consisting of Optical Communications (“OpComms”) and Commercial Lasers (“Lasers”). During the fiscal first quarter of 2024, we changed our organizational structure to better align with trends in our markets and our customer and product mix. Our new operating segments are Cloud & Networking and Industrial Tech. The Cloud & Networking segment includes the Telecom and Datacom product lines that were previously part of the OpComms segment. The Industrial Tech segment includes the previous Lasers segment and the Industrial & Consumer product lines that were previously part of the OpComms segment. Comparative prior period segment information has been recast to conform to the new segment structure and measures. The changes in our operating segments had no impact on our previously reported consolidated results of operations, financial condition, or cash flows. Refer to “Note 15. Operating Segments and Geographic Information”. Our business and operating results depend significantly on general market and economic conditions. The current global macroeconomic environment is volatile and continues to be adversely impacted by inflation, a dynamic supply chain and demand environment, and signs of a weaker macroeconomic environment impacting capital expenditures across our served markets. Additionally, instability in the global credit markets, capital expenditure reductions, unemployment and other labor issues, decline in stock markets, the instability in the geopolitical environment in many parts of the world, and the current global economic challenges continue to put pressure on our business and operating results. We are continuously monitoring both the current developments in the ongoing war between Russia and Ukraine including the related additional export controls and resulting sanctions imposed on Russia and Belarus by the U.S. and other countries, and the recent war between Israel and Hamas. Additional factors, such as increased inflation, escalating energy costs, constrained raw material availability and the related cost increases, could continue to impact the global economy and our business. Although the global implications of the wars are difficult to predict at this time, we do not presently foresee direct material adverse effects on our business. Business Combinations On August 3, 2022, we completed a merger with NeoPhotonics Corporation (“NeoPhotonics”). On August 15, 2022, we completed a transaction to acquire IPG Photonics’ telecom transmission product lines. We have applied the acquisition method of accounting in accordance with ASC Topic 805, Business Combinations to account for both of the transactions. Refer to “Note 4. Business Combinations”. Fiscal Years We utilize a 52-53 week fiscal year ending on the Saturday closest to June 30th. Every fifth or sixth fiscal year will have a 53-week period. The additional week in a 53-week year is added to the third quarter, making such quarter consist of 14 weeks. Our fiscal 2024 is a 52-week year ending on June 29, 2024, with the quarter ended September 30, 2023 being a 13-week quarterly period. Our fiscal 2023 was a 52-week year that ended on July 1, 2023, with the quarter ended October 1, 2022 being a 13-week quarterly period. Principles of Consolidation The condensed consolidated financial statements include the accounts of Lumentum Holdings Inc. and its wholly owned subsidiaries. All inter-company transactions and balances are eliminated in consolidation. Accounting Policies The condensed consolidated financial statements and accompanying notes should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the fiscal year ended July 1, 2023. There were no significant changes to our accounting policies during the three months ended September 30, 2023.