Tax Benefit Preservation Plan / Preferred Stock Rights	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Tax Benefit Preservation Plan / Preferred Stock Rights	TAX BENEFIT PRESERVATION PLAN / PREFERRED STOCK RIGHTS As of December 31, 2018, ATRM had federal net operating loss carryforwards (“NOLs”) of approximately $104.7 million and state NOLs of approximately $23.3 million. Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”), imposes an annual limitation on the amount of taxable income that may be offset by a corporation’s NOLs if the corporation experiences an “ownership change” as defined in Section 382 of the Code. An ownership change occurs when the corporation’s “5-percent shareholders” (as defined in Section 382 of the Code) collectively increase their ownership in the corporation by more than 50 percentage points (by value) over a rolling three-year period. Additionally, various states have similar limitations on the use of state NOLs following an ownership change. On February 13, 2014, to protect the tax benefits of ATRM’s NOLs, the Board adopted a Tax Benefit Preservation Plan (the “Rights Plan”) that generally was designed to deter any person from acquiring shares of ATRM’s common stock if the acquisition would result in such person beneficially owning 4.99% or more of the common stock without the approval of the Board. In connection with the adoption of the Rights Plan, on February 13, 2014, the Board authorized and declared a dividend distribution of one right for each outstanding share of ATRM’s common stock to stockholders of record as of the close of business on February 24, 2014. Each right entitled the registered holder to purchase from the Company one one-thousandth of a share of Series B Stock, par value $0.001 per share, of the Company at an exercise price of $30.00 per one one-thousandth of a Preferred Share, subject to adjustment. Subject to certain exceptions specified in the Rights Plan, the rights were to separate from ATRM’s common stock and become exercisable following (i) the 10th business day (or such later date as may be determined by the Board) after the public announcement that an acquiring person had acquired beneficial ownership of 4.99% or more of ATRM’s common stock or (ii) the 10th business day (or such later date as may be determined by the Board) after a person or group announced a tender or exchange offer that would have resulted in ownership by a person or group of 4.99% or more of ATRM’s common stock. Additionally, at any time after the date on which an acquiring person beneficially owned 4.99% or more, but less than 50%, of ATRM’s common stock, the Board was permitted to exchange the rights (except for rights that were voided due to their beneficial ownership by an acquiring person or group), in whole or in part, for shares of ATRM’s common stock at an exchange ratio of one share per right (subject to adjustment), or in certain circumstances, cash or other securities of the Company having a value approximately equal to one share. The operation of the Rights Plan could have caused substantial dilution to a person or group that acquired 4.99% or more of the Company’s common stock on terms not approved by the Board. The adoption of the Rights Plan had no impact on the Company’s consolidated financial statements for fiscal years 2018 or 2017. No rights were exercisable at December 31, 2018. The Rights Plan expired on February 13, 2017.

TAX BENEFIT PRESERVATION PLAN / PREFERRED STOCK RIGHTS

As of December 31, 2018, ATRM had federal net operating loss carryforwards (“NOLs”) of approximately $104.7 million and state NOLs of approximately $23.3 million. Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”), imposes an annual limitation on the amount of taxable income that may be offset by a corporation’s NOLs if the corporation experiences an “ownership change” as defined in Section 382 of the Code. An ownership change occurs when the corporation’s “5-percent shareholders” (as defined in Section 382 of the Code) collectively increase their ownership in the corporation by more than 50 percentage points (by value) over a rolling three-year period. Additionally, various states have similar limitations on the use of state NOLs following an ownership change.

On February 13, 2014, to protect the tax benefits of ATRM’s NOLs, the Board adopted a Tax Benefit Preservation Plan (the “Rights Plan”) that generally was designed to deter any person from acquiring shares of ATRM’s common stock if the acquisition would result in such person beneficially owning 4.99% or more of the common stock without the approval of the Board.

In connection with the adoption of the Rights Plan, on February 13, 2014, the Board authorized and declared a dividend distribution of one right for each outstanding share of ATRM’s common stock to stockholders of record as of the close of business on February 24, 2014. Each right entitled the registered holder to purchase from the Company one one-thousandth of a share of Series B Stock, par value $0.001 per share, of the Company at an exercise price of $30.00 per one one-thousandth of a Preferred Share, subject to adjustment.

Subject to certain exceptions specified in the Rights Plan, the rights were to separate from ATRM’s common stock and become exercisable following (i) the 10th business day (or such later date as may be determined by the Board) after the public announcement that an acquiring person had acquired beneficial ownership of 4.99% or more of ATRM’s common stock or (ii) the 10th business day (or such later date as may be determined by the Board) after a person or group announced a tender or exchange offer that would have resulted in ownership by a person or group of 4.99% or more of ATRM’s common stock.

Additionally, at any time after the date on which an acquiring person beneficially owned 4.99% or more, but less than 50%, of ATRM’s common stock, the Board was permitted to exchange the rights (except for rights that were voided due to their beneficial ownership by an acquiring person or group), in whole or in part, for shares of ATRM’s common stock at an exchange ratio of one share per right (subject to adjustment), or in certain circumstances, cash or other securities of the Company having a value approximately equal to one share.

The operation of the Rights Plan could have caused substantial dilution to a person or group that acquired 4.99% or more of the Company’s common stock on terms not approved by the Board.

The adoption of the Rights Plan had no impact on the Company’s consolidated financial statements for fiscal years 2018 or 2017. No rights were exercisable at December 31, 2018. The Rights Plan expired on February 13, 2017.