Organization and Nature of Operations	3 Months Ended
Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Nature of Operations	Note 1—Organization and Nature of Operations Ra Medical Systems, Inc. (the “Company”) was formed in September 4, 2002, in the state of California and reincorporated in Delaware on July 14, 2018. The Company is a medical device company that develops, manufactures and markets advanced excimer lasers for use in the treatment of vascular and dermatological diseases. The Company’s product development centers around proprietary applications of its advanced excimer laser technology for use as a tool in the treatment of peripheral artery disease (“PAD”) and psoriasis, vitiligo, atopic dermatitis and leukoderma. In July 2018, the Company reincorporated in Delaware. In connection with the Company’s initial public offering (“IPO”), which closed on October 1, 2018, the Company filed an Amended and Restated Certificate of Incorporation which authorizes the issuance of 300,000,000 shares of common stock with a par value of $0.0001 and 10,000,000 shares of preferred stock with a par value of $0.0001. COVID-19—The global spread of the novel coronavirus (COVID-19) has created significant volatility, uncertainty and economic disruption. The ultimate effects of the COVID-19 on the Company’s business, operations and financial condition are unknown at this time. In the near term, the Company expects that its revenue will be adversely impacted and enrollment in its atherectomy clinical trial will be delayed or slowed, as patients elect to postpone voluntary treatments and physicians’ offices are either closed or operating at a reduced capacity. In addition, some customers are requesting more flexible payment terms on a temporary basis. The Company’s manufacturing facility located in Carlsbad, California is currently operational. Employee travel is limited to essential travel only and many employees are working from home when feasible. Due to the Company’s reduced commercial footprint and volume, it is not currently experiencing any shortages in supplies that would impact its ability to manufacture products sufficient to meet current demand and to support its atherectomy indication trial. However, the extent to which COVID-19 impacts its business will depend on future developments, which are highly uncertain and cannot be predicted, including new information which may emerge concerning the severity of COVID-19 and the actions to contain it or treat its impact, among others. Going Concern — The condensed financial statements have been prepared on a going concern basis, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of this uncertainty. The Company has experienced recurring net losses from operations and negative cash flows from operating activities, has a significant accumulated deficit and expects to continue to incur net losses into the foreseeable future. The Company had an accumulated deficit of $124.9 million at March 31, 2020. In 2019, the Company used $33.2 million for operating activities. As of March 31, 2020, the Company had cash, cash equivalents and short-term investments of $23.4 million. Management expects operating losses and negative cash flows to continue for the foreseeable future with the Company’s reduced commercial footprint, and as the Company continues to incur costs related to its atherectomy clinical trial, engineering efforts to improve the shelf-life of its catheters and develop next generation products and legal costs associated with ongoing litigation. The Company also expects the COVID-19 pandemic to have a negative impact on its revenue and timing of enrollment in its atherectomy clinical trial, as well as the Company’s ability to secure additional financing in a timely manner or on favorable terms, if at all. Management estimates that based on the Company’s liquidity resources, there is substantial doubt about the Company’s ability to continue as a going concern within 12 months from the date of issuance of the financial statements. Management’s ability to continue as a going concern is dependent upon its ability to raise additional funding. Management’s plans to raise additional capital through public or private equity or debt financings to fulfill its operating and capital requirements for at least 12 months from the date of the issuance of the financial statements. However, the Company may not be able to secure such financing in a timely manner or on favorable terms, if at all. Furthermore, if the Company issues equity securities to raise additional funds, its existing stockholders may experience dilution, and the new equity securities may have rights, preferences and privileges senior to those of the Company’s existing stockholders.

Organization and Nature of Operations

3 Months Ended

Mar. 31, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Note 1—Organization and Nature of Operations

Ra Medical Systems, Inc. (the “Company”) was formed in September 4, 2002, in the state of California and reincorporated in Delaware on July 14, 2018. The Company is a medical device company that develops, manufactures and markets advanced excimer lasers for use in the treatment of vascular and dermatological diseases. The Company’s product development centers around proprietary applications of its advanced excimer laser technology for use as a tool in the treatment of peripheral artery disease (“PAD”) and psoriasis, vitiligo, atopic dermatitis and leukoderma.

In July 2018, the Company reincorporated in Delaware. In connection with the Company’s initial public offering (“IPO”), which closed on October 1, 2018, the Company filed an Amended and Restated Certificate of Incorporation which authorizes the issuance of 300,000,000 shares of common stock with a par value of $0.0001 and 10,000,000 shares of preferred stock with a par value of $0.0001.

COVID-19—The global spread of the novel coronavirus (COVID-19) has created significant volatility, uncertainty and economic disruption. The ultimate effects of the COVID-19 on the Company’s business, operations and financial condition are unknown at this time. In the near term, the Company expects that its revenue will be adversely impacted and enrollment in its atherectomy clinical trial will be delayed or slowed, as patients elect to postpone voluntary treatments and physicians’ offices are either closed or operating at a reduced capacity. In addition, some customers are requesting more flexible payment terms on a temporary basis. The Company’s manufacturing facility located in Carlsbad, California is currently operational. Employee travel is limited to essential travel only and many employees are working from home when feasible. Due to the Company’s reduced commercial footprint and volume, it is not currently experiencing any shortages in supplies that would impact its ability to manufacture products sufficient to meet current demand and to support its atherectomy indication trial. However, the extent to which COVID-19 impacts its business will depend on future developments, which are highly uncertain and cannot be predicted, including new information which may emerge concerning the severity of COVID-19 and the actions to contain it or treat its impact, among others.

Going Concern — The condensed financial statements have been prepared on a going concern basis, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of this uncertainty.

The Company has experienced recurring net losses from operations and negative cash flows from operating activities, has a significant accumulated deficit and expects to continue to incur net losses into the foreseeable future. The Company had an accumulated deficit of $124.9 million at March 31, 2020. In 2019, the Company used $33.2 million for operating activities. As of March 31, 2020, the Company had cash, cash equivalents and short-term investments of $23.4 million. Management expects operating losses and negative cash flows to continue for the foreseeable future with the Company’s reduced commercial footprint, and as the Company continues to incur costs related to its atherectomy clinical trial, engineering efforts to improve the shelf-life of its catheters and develop next generation products and legal costs associated with ongoing litigation. The Company also expects the COVID-19 pandemic to have a negative impact on its revenue and timing of enrollment in its atherectomy clinical trial, as well as the Company’s ability to secure additional financing in a timely manner or on favorable terms, if at all.

Management estimates that based on the Company’s liquidity resources, there is substantial doubt about the Company’s ability to continue as a going concern within 12 months from the date of issuance of the financial statements.

Management’s ability to continue as a going concern is dependent upon its ability to raise additional funding. Management’s plans to raise additional capital through public or private equity or debt financings to fulfill its operating and capital requirements for at least 12 months from the date of the issuance of the financial statements. However, the Company may not be able to secure such financing in a timely manner or on favorable terms, if at all. Furthermore, if the Company issues equity securities to raise additional funds, its existing stockholders may experience dilution, and the new equity securities may have rights, preferences and privileges senior to those of the Company’s existing stockholders.