Income Taxes	9 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes In general, the variation between the Company's effective income tax rate and the U.S. statutory rate of 21% is primarily due to: (i) changes in the Company’s valuation allowances against deferred tax assets in the U.S. and Luxembourg, (ii) projected income for the full year derived from international locations with lower tax rates than the U.S. and (iii) projected tax credits generated. In December 2017, the SEC staff issued Staff Accounting Bulletin 118 (SAB 118) to provide guidance on accounting for the tax effects of the Tax Cuts and Jobs Act of 2017 (Tax Legislation) enacted on December 22, 2017. SAB 118 allowed for a measurement period, not to extend beyond one year from the Tax Legislation date of enactment, for companies to complete the accounting under ASC Topic 740-Income Taxes. The SAB 118 measurement period concluded during the six months ended December 30, 2018, and consistent with the guidance provided in SAB 118, the Company has completed the accounting for the income tax effects of the Tax Legislation. The Company assesses all available positive and negative evidence to estimate if sufficient future taxable income will be generated to utilize the existing deferred tax assets by jurisdiction. The Company has concluded that it is necessary to recognize a full valuation allowance against its U.S. and Luxembourg deferred tax assets, as of the nine months ended March 31, 2019. While the Company concludes a full U.S. valuation allowance is appropriate as of March 31, 2019, as a result of improving Company performance and future U.S. projected income, it is reasonably possible that the assessment of the realizability of the U.S. deferred tax assets could change within the next twelve months resulting in a full or partial release of the U.S. valuation allowance. As of June 24, 2018, the U.S. valuation allowance was $122.2 million. During the nine months ended March 31, 2019, the Company increased the U.S. valuation allowance by $8.8 million due to the deferred tax impact of the Lighting Products business impairment and the sale of Cree Canada Corp. and Cree Europe S.r.l., offset by the deferred tax impact of the Notes issuance and the impact of the Internal Revenue Code Section 965(n) election related to the accounting of the Tax Legislation. As of June 24, 2018, the Luxembourg valuation allowance was $5.2 million. During the nine months ended March 31, 2019, the Company increased this valuation allowance by $5.0 million due to year-to-date losses in Luxembourg. U.S. GAAP requires a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the 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 cumulatively more than 50% likely to be realized upon ultimate settlement. As of June 24, 2018, the Company's liability for unrecognized tax benefits was $8.7 million. During the nine months ended March 31, 2019, the Company recorded a $0.2 million decrease to the liability for unrecognized tax benefits resulting from a $0.5 million increase related to intercompany transactions recently challenged by the German tax authority, offset by a $0.7 million decrease due to statue expiration. As a result, the total liability for unrecognized tax benefits as of March 31, 2019 was $8.5 million. If any portion of this $8.5 million is recognized, the Company will then include that portion in the computation of its effective tax rate. Although the ultimate timing of the resolution and/or closure of audits is highly uncertain, the Company believes it is reasonably possible that $1.1 million of gross unrecognized tax benefits will change in the next 12 months as a result of statute requirements or settlement with tax authorities. The Company files U.S. federal, U.S. state and foreign tax returns. For U.S. federal purposes, the Company is generally no longer subject to tax examinations for fiscal years prior to 2016. For U.S. state tax returns, the Company is generally no longer subject to tax examinations for fiscal years prior to 2015. For foreign purposes, the Company is generally no longer subject to examination for tax periods prior to 2008. Certain carryforward tax attributes generated in prior years remain subject to examination, adjustment and recapture.

Income Taxes

In general, the variation between the Company's effective income tax rate and the U.S. statutory rate of 21% is primarily due to: (i) changes in the Company’s valuation allowances against deferred tax assets in the U.S. and Luxembourg, (ii) projected income for the full year derived from international locations with lower tax rates than the U.S. and (iii) projected tax credits generated.

In December 2017, the SEC staff issued Staff Accounting Bulletin 118 (SAB 118) to provide guidance on accounting for the tax effects of the Tax Cuts and Jobs Act of 2017 (Tax Legislation) enacted on December 22, 2017. SAB 118 allowed for a measurement period, not to extend beyond one year from the Tax Legislation date of enactment, for companies to complete the accounting under ASC Topic 740-Income Taxes. The SAB 118 measurement period concluded during the six months ended December 30, 2018, and consistent with the guidance provided in SAB 118, the Company has completed the accounting for the income tax effects of the Tax Legislation.

The Company assesses all available positive and negative evidence to estimate if sufficient future taxable income will be generated to utilize the existing deferred tax assets by jurisdiction. The Company has concluded that it is necessary to recognize a full valuation allowance against its U.S. and Luxembourg deferred tax assets, as of the nine months ended March 31, 2019.

While the Company concludes a full U.S. valuation allowance is appropriate as of March 31, 2019, as a result of improving Company performance and future U.S. projected income, it is reasonably possible that the assessment of the realizability of the U.S. deferred tax assets could change within the next twelve months resulting in a full or partial release of the U.S. valuation allowance. As of June 24, 2018, the U.S. valuation allowance was $122.2 million. During the nine months ended March 31, 2019, the Company increased the U.S. valuation allowance by $8.8 million due to the deferred tax impact of the Lighting Products business impairment and the sale of Cree Canada Corp. and Cree Europe S.r.l., offset by the deferred tax impact of the Notes issuance and the impact of the Internal Revenue Code Section 965(n) election related to the accounting of the Tax Legislation. As of June 24, 2018, the Luxembourg valuation allowance was $5.2 million. During the nine months ended March 31, 2019, the Company increased this valuation allowance by $5.0 million due to year-to-date losses in Luxembourg.

U.S. GAAP requires a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the 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 cumulatively more than 50% likely to be realized upon ultimate settlement.

As of June 24, 2018, the Company's liability for unrecognized tax benefits was $8.7 million. During the nine months ended March 31, 2019, the Company recorded a $0.2 million decrease to the liability for unrecognized tax benefits resulting from a $0.5 million increase related to intercompany transactions recently challenged by the German tax authority, offset by a $0.7 million decrease due to statue expiration. As a result, the total liability for unrecognized tax benefits as of March 31, 2019 was $8.5 million. If any portion of this $8.5 million is recognized, the Company will then include that portion in the computation of its effective tax rate. Although the ultimate timing of the resolution and/or closure of audits is highly uncertain, the Company believes it is reasonably possible that $1.1 million of gross unrecognized tax benefits will change in the next 12 months as a result of statute requirements or settlement with tax authorities.

The Company files U.S. federal, U.S. state and foreign tax returns. For U.S. federal purposes, the Company is generally no longer subject to tax examinations for fiscal years prior to 2016. For U.S. state tax returns, the Company is generally no longer subject to tax examinations for fiscal years prior to 2015. For foreign purposes, the Company is generally no longer subject to examination for tax periods prior to 2008. Certain carryforward tax attributes generated in prior years remain subject to examination, adjustment and recapture.