Income Taxes	9 Months Ended
Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to income tax in the United States as well as other tax jurisdictions in which it conducts business. Earnings from non-U.S. activities are subject to local country income tax. The Company does not provide for federal income taxes on the undistributed earnings of its foreign subsidiaries as such earnings are to be reinvested indefinitely. The Company recorded an income tax benefit of $0.1 million and income tax provision of $0.2 million for the three months ended December 31, 2018 and 2017, respectively, and an income tax provision of $0.4 million and $0.6 million for the nine months ended December 31, 2018 and 2017, respectively, related to foreign income taxes and state minimum taxes. Based on the available objectively verifiable evidence during the three and nine months ended December 31, 2018, the Company believes it is more likely than not that the tax benefits of the U.S. losses and New Relic K.K losses incurred during the three and nine months ended December 31, 2018 may not be realized. Accordingly, the Company did not record the tax benefits for U.S. losses and New Relic K.K losses incurred during the three and nine months ended December 31, 2018. The primary difference between the effective tax rate and the statutory tax rate relates to the valuation allowance on the Company’s U.S. losses and New Relic K.K losses and foreign tax rate differences. On December 22, 2017, the “Tax Cuts and Jobs Act” (the “TCJA”) was enacted into law. The TCJA includes significant changes to the U.S corporate Internal Revenue Code of 1986, as amended (the “Code”). The TCJA changes include, but are not limited to, reduction in the U.S. corporate tax rate from 35% to 21% effective for tax years beginning after December 31, 2017, limitations on the deductibility of executive compensation, interest expense and net operating loss (“NOL”) immediate expensing of capital expenditures, transition of the U.S. international taxation from a “worldwide” system to a territorial system of taxation and the introduction of a base erosion anti-abuse tax (“BEAT”) and Global Intangible Low Taxed Income (“GILTI”) and a new minimum tax on certain foreign earnings. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (“SAB 118”), which allows the Company to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. These provisional tax effects may differ during the measurement period, due to further updates to the calculations related to changes in interpretations and assumptions made, and additional guidance that may be issued by the Department of the U.S. Treasury, the Internal Revenue Service, and other regulatory and standard setting bodies. During the fourth quarter of fiscal year 2018, the Company recorded provisional amounts in its consolidated financial statements. During the third quarter of fiscal year 2019, the Company made adjustments to the provisional amounts, including continued refinements to its deferred taxes. The adjustments made to the provisional amounts include an increase in the depreciation deduction, the “Transition Tax” and NOL carryforward. The analysis and accounting for the tax effects of the TCJA were completed in the third quarter of fiscal 2019. Any subsequent adjustment to these amounts will be recorded as a change in tax law.

Income Taxes

The Company is subject to income tax in the United States as well as other tax jurisdictions in which it conducts business. Earnings from non-U.S. activities are subject to local country income tax. The Company does not provide for federal income taxes on the undistributed earnings of its foreign subsidiaries as such earnings are to be reinvested indefinitely.

The Company recorded an income tax benefit of $0.1 million and income tax provision of $0.2 million for the three months ended December 31, 2018 and 2017, respectively, and an income tax provision of $0.4 million and $0.6 million for the nine months ended December 31, 2018 and 2017, respectively, related to foreign income taxes and state minimum taxes. Based on the available objectively verifiable evidence during the three and nine months ended December 31, 2018, the Company believes it is more likely than not that the tax benefits of the U.S. losses and New Relic K.K losses incurred during the three and nine months ended December 31, 2018 may not be realized. Accordingly, the Company did not record the tax benefits for U.S. losses and New Relic K.K losses incurred during the three and nine months ended December 31, 2018. The primary difference between the effective tax rate and the statutory tax rate relates to the valuation allowance on the Company’s U.S. losses and New Relic K.K losses and foreign tax rate differences.

On December 22, 2017, the “Tax Cuts and Jobs Act” (the “TCJA”) was enacted into law. The TCJA includes significant changes to the U.S corporate Internal Revenue Code of 1986, as amended (the “Code”). The TCJA changes include, but are not limited to, reduction in the U.S. corporate tax rate from 35% to 21% effective for tax years beginning after December 31, 2017, limitations on the deductibility of executive compensation, interest expense and net operating loss (“NOL”) immediate expensing of capital expenditures, transition of the U.S. international taxation from a “worldwide” system to a territorial system of taxation and the introduction of a base erosion anti-abuse tax (“BEAT”) and Global Intangible Low Taxed Income (“GILTI”) and a new minimum tax on certain foreign earnings.

In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (“SAB 118”), which allows the Company to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. These provisional tax effects may differ during the measurement period, due to further updates to the calculations related to changes in interpretations and assumptions made, and additional guidance that may be issued by the Department of the U.S. Treasury, the Internal Revenue Service, and other regulatory and standard setting bodies. During the fourth quarter of fiscal year 2018, the Company recorded provisional amounts in its consolidated financial statements. During the third quarter of fiscal year 2019, the Company made adjustments to the provisional amounts, including continued refinements to its deferred taxes. The adjustments made to the provisional amounts include an increase in the depreciation deduction, the “Transition Tax” and NOL carryforward. The analysis and accounting for the tax effects of the TCJA were completed in the third quarter of fiscal 2019. Any subsequent adjustment to these amounts will be recorded as a change in tax law.