Business Overview	12 Months Ended
Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Overview	Business Overview Immunomedics, Inc., a Delaware corporation (“Immunomedics” or the “Company”), is a clinical-stage biopharmaceutical company that develops monoclonal antibody-based products for the targeted treatment of cancer. Our corporate objective is to become a fully-integrated biopharmaceutical company and a leader in the field of antibody-drug conjugates (“ADCs”). To that end, our immediate priority is to commercialize our most advanced ADC product candidate, sacituzumab govitecan (“IMMU-132”), beginning in the United States ("United States"), with metastatic triple-negative breast cancer (“mTNBC”) as the first indication. On May 21, 2018 we submitted a Biologics License Application (“BLA”) to the FDA for sacituzumab govitecan for the treatment of patients with mTNBC who have received at least two prior therapies for metastatic disease. On July 18, 2018 we received notification from the Food and Drug Administration ("FDA") that the BLA was accepted for filing and granted Priority Review with a PDUFA target action date of January 18, 2019. If approved, sacituzumab govitecan would be the first and only ADC approved for the treatment of mTNBC. The Company has two foreign subsidiaries, Immunomedics B.V. in the Netherlands and Immunomedics GmbH in Rodermark, Germany, that assists the Company in clinical trials in Europe. The accompanying financial statements include results for its two foreign subsidiaries and its majority-owned United States subsidiary, IBC Pharmaceuticals, Inc. ("IBC"). Immunomedics is subject to significant risks and uncertainties, including, without limitation, the Company's inability to further identify, develop and achieve commercial success for new products and technologies; the possibility of delays in the research and development necessary to select drug development candidates and delays in clinical trials; the risk that clinical trials may not result in marketable products; the risk that the Company may be unable to secure regulatory approval of and market its drug candidates; the development or regulatory approval of competing products; the Company's ability to protect its proprietary technologies; patent infringement claims; and risks of new, changing and competitive technologies and regulations in the United States and internationally. Since its inception in 1982, Immunomedics’ principal sources of funds have been the private and public sale of equity and debt securities, and revenues from licensing agreements, including up-front and milestone payments, funding of development programs, and other forms of funding from collaborations. Historically, sources of revenue have included sales of LeukoScan^®, grants, and license fees and other revenue, however, in order to focus on its ADC business, the Company discontinued the sale of LeukoScan^® during February 2018. As of June 30, 2018 we had $638.8 million in cash, cash equivalents and marketable securities. On June 15, 2018, we announced the closing of our public offering of 11,500,000 shares of our common stock at a price of $24.00 per share. Pursuant to the underwriter's full exercise of the over-allotment option granted by us, on June 22, 2018, we closed the sale of an additional 1,725,000 shares of our common stock. The total net proceeds from the offering, including the exercise of the over-allotment option, were $299.5 million, after deducting $17.4 million in underwriting discounts and commissions and other offering expenses payable by the Company. This funding will be used primarily to accelerate the clinical development program of sacituzumab govitecan, manufacturing process improvements as well as for working capital and general corporate purposes. On January 7, 2018, we announced that we sold tiered, sales-based royalty rights on global net sales of sacituzumab govitecan to RPI Finance Trust (“RPI”) for $175.0 million. RPI also purchased $75.0 million in our common stock at $17.15 per share, which represented a more than 15% premium over the stock’s 15-day trailing average closing price at that time. The total $250.0 million funding provided us with the resources required to support our next phase of growth as we focus on developing sacituzumab govitecan in mTNBC, advanced UC and other indications of high medical need and on further building its clinical, medical affairs, commercial and manufacturing infrastructure and to fund operations. The Company expects to continue to fund its operations with its current financial resources.

Business Overview

Immunomedics, Inc., a Delaware corporation (“Immunomedics” or the “Company”), is a clinical-stage biopharmaceutical company that develops monoclonal antibody-based products for the targeted treatment of cancer. Our corporate objective is to become a fully-integrated biopharmaceutical company and a leader in the field of antibody-drug conjugates (“ADCs”). To that end, our immediate priority is to commercialize our most advanced ADC product candidate, sacituzumab govitecan (“IMMU-132”), beginning in the United States ("United States"), with metastatic triple-negative breast cancer (“mTNBC”) as the first indication. On May 21, 2018 we submitted a Biologics License Application (“BLA”) to the FDA for sacituzumab govitecan for the treatment of patients with mTNBC who have received at least two prior therapies for metastatic disease. On July 18, 2018 we received notification from the Food and Drug Administration ("FDA") that the BLA was accepted for filing and granted Priority Review with a PDUFA target action date of January 18, 2019. If approved, sacituzumab govitecan would be the first and only ADC approved for the treatment of mTNBC.

The Company has two foreign subsidiaries, Immunomedics B.V. in the Netherlands and Immunomedics GmbH in Rodermark, Germany, that assists the Company in clinical trials in Europe. The accompanying financial statements include results for its two foreign subsidiaries and its majority-owned United States subsidiary, IBC Pharmaceuticals, Inc. ("IBC").

Immunomedics is subject to significant risks and uncertainties, including, without limitation, the Company's inability to further identify, develop and achieve commercial success for new products and technologies; the possibility of delays in the research and development necessary to select drug development candidates and delays in clinical trials; the risk that clinical trials may not result in marketable products; the risk that the Company may be unable to secure regulatory approval of and market its drug candidates; the development or regulatory approval of competing products; the Company's ability to protect its proprietary technologies; patent infringement claims; and risks of new, changing and competitive technologies and regulations in the United States and internationally.

Since its inception in 1982, Immunomedics’ principal sources of funds have been the private and public sale of equity and debt securities, and revenues from licensing agreements, including up-front and milestone payments, funding of development programs, and other forms of funding from collaborations. Historically, sources of revenue have included sales of LeukoScan^®, grants, and license fees and other revenue, however, in order to focus on its ADC business, the Company discontinued the sale of LeukoScan^® during February 2018.

As of June 30, 2018 we had $638.8 million in cash, cash equivalents and marketable securities. On June 15, 2018, we announced the closing of our public offering of 11,500,000 shares of our common stock at a price of $24.00 per share. Pursuant to the underwriter's full exercise of the over-allotment option granted by us, on June 22, 2018, we closed the sale of an additional 1,725,000 shares of our common stock. The total net proceeds from the offering, including the exercise of the over-allotment option, were $299.5 million, after deducting $17.4 million in underwriting discounts and commissions and other offering expenses payable by the Company. This funding will be used primarily to accelerate the clinical development program of sacituzumab govitecan, manufacturing process improvements as well as for working capital and general corporate purposes.

On January 7, 2018, we announced that we sold tiered, sales-based royalty rights on global net sales of sacituzumab govitecan to RPI Finance Trust (“RPI”) for $175.0 million. RPI also purchased $75.0 million in our common stock at $17.15 per share, which represented a more than 15% premium over the stock’s 15-day trailing average closing price at that time. The total $250.0 million funding provided us with the resources required to support our next phase of growth as we focus on developing sacituzumab govitecan in mTNBC, advanced UC and other indications of high medical need and on further building its clinical, medical affairs, commercial and manufacturing infrastructure and to fund operations.

The Company expects to continue to fund its operations with its current financial resources.