Basis of Presentation (Policies)	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	The accompanying Condensed Consolidated Financial Statements of ADES are unaudited and have been prepared in conformity with accounting principles generally accepted in the United States ("U.S. GAAP") and with Article 10 of Regulation S-X of the Securities and Exchange Commission. In compliance with those instructions, certain information and footnote disclosures normally included in annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The unaudited Condensed Consolidated Financial Statements of ADES in this quarterly report ("Quarterly Report") are presented on a consolidated basis and include ADES and its wholly-owned subsidiaries (collectively, the "Company"). Also included within the unaudited Condensed Consolidated Financial Statements are the Company's unconsolidated equity investments: Tinuum Group, Tinuum Services and GWN Manager, LLC ("GWN Manager"), which are accounted for under the equity method of accounting, and Highview Enterprises Limited (the "Highview Investment"), which is accounted for in accordance with U.S. GAAP applicable to equity investments that do not qualify for the equity method of accounting. Results of operations and cash flows for the interim periods are not necessarily indicative of the results that may be expected for the entire year. All significant intercompany transactions and accounts were eliminated in consolidation for all periods presented in this Quarterly Report. In the opinion of management, these Condensed Consolidated Financial Statements include all normal and recurring adjustments considered necessary for a fair presentation of the results of operations, financial position, stockholders' equity and cash flows for the interim periods presented. These Condensed Consolidated Financial Statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 (the "2020 Form 10-K").
Earnings (Loss) Per Share	Basic earnings (loss) per share is computed using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for common stock and any participating securities according to dividend and participating rights in undistributed earnings (losses). Pursuant to U.S. GAAP, the Company has elected not to separately present basic or diluted earnings per share attributable to participating securities in the Condensed Consolidated Statements of Operations. Diluted earnings (loss) per share is computed in a manner consistent with that of basic earnings per share, while considering other potentially dilutive securities. For the three and nine months ended September 30, 2021, potentially dilutive securities consist of unvested non-participating restricted stock awards ("RSA's"), as well as contingent performance stock units ("PSU's"). For the three and nine months ended September 30, 2020, potentially dilutive securities consist of both unvested, participating and non-participating RSA's, as well as outstanding options to purchase common stock ("Stock Options") and PSU's. The dilutive effect, if any, for non-participating RSA's, Stock Options and PSU's is determined using the greater of dilution as calculated under the treasury stock method or the two-class method. Potentially dilutive securities are excluded from diluted earnings per share when their effect is anti-dilutive. When there is a net loss for a period, all potentially dilutive securities are anti-dilutive and are excluded from the calculation of diluted loss per share for that period.
Use of Estimates	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. There have been no changes in the Company’s critical accounting estimates from those that were disclosed in the 2020 Form 10-K. Actual results could differ from these estimates.
Risks and Uncertainties	The Company’s earnings are significantly affected by equity earnings from Tinuum Group. As of September 30, 2021, Tinuum Group has 16 invested RC facilities, of which 5 are leased to a single customer. Both Tinuum Group and Tinuum Services are winding down their operations due to the expected expiration of the Section 45 tax credit period as of December 31, 2021. As of September 30, 2021, Tinuum Group ceased operating seven RC facilities, with the remaining RC facilities expected to cease operations during the fourth quarter of 2021. The loss of Tinuum Group's customers, reduction in revenue streams as a result of lease renewals and the expiration of Section 45 tax credits will have a significant adverse impact on Tinuum Group's financial position, results of operations and cash flows, which in turn will have a material adverse impact on the Company’s financial position, results of operations and cash flows.The Company's revenues, sales volumes, earnings and cash flows are significantly affected by prices of competing power generation sources such as natural gas and renewable energy. During periods of low natural gas prices, natural gas provides a competitive alternative to coal-fired power generation and therefore, coal consumption may be reduced, which in turn reduces the demand for the Company's products. However, during periods of higher prices for competing power generation sources, there is an increase in coal consumption and thus demand for the Company's products also increase. In addition, coal consumption and demand for the Company's products are also affected by the demand for electricity, which is higher in the warmer and colder months of the year. Abnormal temperatures during the summer and winter months may significantly affect coal consumption and thus the demand for the Company's products.The Company's financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents. The Company holds cash and cash equivalents at three financial institutions as of September 30, 2021. If an institution was unable to perform its obligations, the Company would be at risk regarding the amount of cash and investments in excess of the Federal Deposit Insurance Corporation limits (currently $250 thousand) that would be returned to the Company.
Reclassifications	Certain balances have been reclassified from the prior year to conform to the current year presentation. Such reclassifications had no effect on the Company’s results of operations or financial position in any of the periods presented.
New Accounting Standards	In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). The main objective of ASU 2016-13 is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. To achieve this objective, the amendments in ASU 2016-13 replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to form credit loss estimates. ASU 2016-13 is effective for "smaller reporting companies" (as defined by the Securities and Exchange Commission) for fiscal years beginning after December 15, 2022, including interim periods within those years, and must be adopted under a modified retrospective method approach. The Company is currently evaluating the provisions of this guidance and assessing the impact on its financial statements and disclosures and does not believe this standard will have a material impact on its financial statements and disclosures.
Business Segment Information	Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by a company's chief operating decision maker ("CODM"), or a decision-making group, to allocate resources and assess financial performance. As of September 30, 2021, the Company's CODM was the Company's CEO. The Company's operating and reportable segments are identified by products and services provided. As of September 30, 2021, the Company has two reportable segments: (1) Refined Coal ("RC"); and (2) Advanced Purification Technologies ("APT"). Effective December 31, 2020, and as reported in the 2020 Form 10-K, the Company revised its segments to RC and APT, and amounts for the three and nine months ended September 30, 2020 have been recast to conform with the current year presentation. Both Tinuum Group and Tinuum Services are significantly winding down their operations due to the expected expiration of the Section 45 tax credit period as of December 31, 2021. As such, the Company's earnings and distributions from our RC segment will substantially cease as of December 31, 2021. The business segment measurements provided to and evaluated by the CODM are computed in accordance with the principles listed below: •The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies in the 2020 Form 10-K. •Segment revenues include equity method earnings and losses from the Company's equity method investments. •Segment operating income (loss) includes segment revenues and allocation of certain "Corporate general and administrative expenses," which include Payroll and benefits, General and administrative and Depreciation, amortization, depletion and accretion. •RC segment operating income includes interest expense directly attributable to the RC segment.
Fair Value of Financial Instruments	The carrying amounts of financial instruments, including cash, cash equivalents and restricted cash, accounts receivable, accounts payable and accrued expenses, approximate fair value due to the short maturity of these instruments.

Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2021

The accompanying Condensed Consolidated Financial Statements of ADES are unaudited and have been prepared in conformity with accounting principles generally accepted in the United States ("U.S. GAAP") and with Article 10 of Regulation S-X of the Securities and Exchange Commission. In compliance with those instructions, certain information and footnote disclosures normally included in annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted.

The unaudited Condensed Consolidated Financial Statements of ADES in this quarterly report ("Quarterly Report") are presented on a consolidated basis and include ADES and its wholly-owned subsidiaries (collectively, the "Company"). Also included within the unaudited Condensed Consolidated Financial Statements are the Company's unconsolidated equity investments: Tinuum Group, Tinuum Services and GWN Manager, LLC ("GWN Manager"), which are accounted for under the equity method of accounting, and Highview Enterprises Limited (the "Highview Investment"), which is accounted for in accordance with U.S. GAAP applicable to equity investments that do not qualify for the equity method of accounting.

Results of operations and cash flows for the interim periods are not necessarily indicative of the results that may be expected for the entire year. All significant intercompany transactions and accounts were eliminated in consolidation for all periods presented in this Quarterly Report.

In the opinion of management, these Condensed Consolidated Financial Statements include all normal and recurring adjustments considered necessary for a fair presentation of the results of operations, financial position, stockholders' equity and cash flows for the interim periods presented. These Condensed Consolidated Financial Statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 (the "2020 Form 10-K").

Earnings (Loss) Per Share

Basic earnings (loss) per share is computed using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for common stock and any participating securities according to dividend and participating rights in undistributed earnings (losses). Pursuant to U.S. GAAP, the Company has elected not to separately present basic or diluted earnings per share attributable to participating securities in the Condensed Consolidated Statements of Operations.

Diluted earnings (loss) per share is computed in a manner consistent with that of basic earnings per share, while considering other potentially dilutive securities. For the three and nine months ended September 30, 2021, potentially dilutive securities consist of unvested non-participating restricted stock awards ("RSA's"), as well as contingent performance stock units ("PSU's"). For the three and nine months ended September 30, 2020, potentially dilutive securities consist of both unvested, participating and non-participating RSA's, as well as outstanding options to purchase common stock ("Stock Options") and PSU's.

The dilutive effect, if any, for non-participating RSA's, Stock Options and PSU's is determined using the greater of dilution as calculated under the treasury stock method or the two-class method. Potentially dilutive securities are excluded from diluted earnings per share when their effect is anti-dilutive. When there is a net loss for a period, all potentially dilutive securities are anti-dilutive and are excluded from the calculation of diluted loss per share for that period.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. There have been no changes in the Company’s critical accounting estimates from those that were disclosed in the 2020 Form 10-K. Actual results could differ from these estimates.

Risks and Uncertainties

The Company’s earnings are significantly affected by equity earnings from Tinuum Group. As of September 30, 2021, Tinuum Group has 16 invested RC facilities, of which 5 are leased to a single customer. Both Tinuum Group and Tinuum Services are winding down their operations due to the expected expiration of the Section 45 tax credit period as of December 31, 2021. As of September 30, 2021, Tinuum Group ceased operating seven RC facilities, with the remaining RC facilities expected to cease operations during the fourth quarter of 2021. The loss of Tinuum Group's customers, reduction in revenue streams as a result of lease renewals and the expiration of Section 45 tax credits will have a significant adverse impact on Tinuum Group's financial position, results of operations and cash flows, which in turn will have a material adverse impact on the Company’s financial position, results of operations and cash flows.The Company's revenues, sales volumes, earnings and cash flows are significantly affected by prices of competing power generation sources such as natural gas and renewable energy. During periods of low natural gas prices, natural gas provides a competitive alternative to coal-fired power generation and therefore, coal consumption may be reduced, which in turn reduces the demand for the Company's products. However, during periods of higher prices for competing power generation sources, there is an increase in coal consumption and thus demand for the Company's products also increase. In addition, coal consumption and demand for the Company's products are also affected by the demand for electricity, which is higher in the warmer and colder months of the year. Abnormal temperatures during the summer and winter months may significantly affect coal consumption and thus the demand for the Company's products.The Company's financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents. The Company holds cash and cash equivalents at three financial institutions as of September 30, 2021. If an institution was unable to perform its obligations, the Company would be at risk regarding the amount of cash and investments in excess of the Federal Deposit Insurance Corporation limits (currently $250 thousand) that would be returned to the Company.

Reclassifications

Certain balances have been reclassified from the prior year to conform to the current year presentation. Such reclassifications had no effect on the Company’s results of operations or financial position in any of the periods presented.

New Accounting Standards

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). The main objective of ASU 2016-13 is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. To achieve this objective, the amendments in ASU 2016-13 replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to form credit loss estimates. ASU 2016-13 is effective for "smaller reporting companies" (as defined by the Securities and Exchange Commission) for fiscal years beginning after December 15, 2022, including interim periods within those years, and must be adopted under a modified retrospective method approach. The Company is currently evaluating the provisions of this guidance and assessing the impact on its financial statements and disclosures and does not believe this standard will have a material impact on its financial statements and disclosures.

Business Segment Information

Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by a company's chief operating decision maker ("CODM"), or a decision-making group, to allocate

resources and assess financial performance. As of September 30, 2021, the Company's CODM was the Company's CEO. The Company's operating and reportable segments are identified by products and services provided.

As of September 30, 2021, the Company has two reportable segments: (1) Refined Coal ("RC"); and (2) Advanced Purification Technologies ("APT"). Effective December 31, 2020, and as reported in the 2020 Form 10-K, the Company revised its segments to RC and APT, and amounts for the three and nine months ended September 30, 2020 have been recast to conform with the current year presentation. Both Tinuum Group and Tinuum Services are significantly winding down their operations due to the expected expiration of the Section 45 tax credit period as of December 31, 2021. As such, the Company's earnings and distributions from our RC segment will substantially cease as of December 31, 2021.

The business segment measurements provided to and evaluated by the CODM are computed in accordance with the principles listed below:

•The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies in the 2020 Form 10-K.

•Segment revenues include equity method earnings and losses from the Company's equity method investments.

•Segment operating income (loss) includes segment revenues and allocation of certain "Corporate general and administrative expenses," which include Payroll and benefits, General and administrative and Depreciation, amortization, depletion and accretion.

•RC segment operating income includes interest expense directly attributable to the RC segment.

Fair Value of Financial Instruments

The carrying amounts of financial instruments, including cash, cash equivalents and restricted cash, accounts receivable, accounts payable and accrued expenses, approximate fair value due to the short maturity of these instruments.