Summary of Significant Accounting Policies	3 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Unaudited Interim Financial Information The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and the rules and regulations of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal, recurring adjustments considered necessary for a fair presentation, have been included, and intercompany transactions and accounts have been eliminated in consolidation. The information disclosed in the notes to the condensed consolidated financial statements for these periods is unaudited. Operating results for the three months ended December 31, 2021 are not necessarily indicative of the results that may be expected for the year ending September 30, 2022 or for any future period. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect amounts in the condensed consolidated financial statements and accompanying notes. For the three months ended December 31, 2021, these estimates required the Company to make assumptions about the extent and duration of restrictions on cross-border transactions and the impact of the COVID-19 pandemic on macroeconomic conditions and, in turn, the Company's results of operations. As there remains uncertainty associated with the COVID-19 pandemic, the Company will continue to update its assumptions as conditions change. Actual results could differ significantly from those estimates. Contract Assets and Liabilities Contract assets reflect an estimate of expenses that will be reimbursed upon settlement with a seller. The contract asset balance was $0.7 million as of December 31, 2021 and $0.6 million as of September 30, 2021 and is included in the line item Prepaid expenses and other current assets on the Condensed Consolidated Balance Sheets. Contract liabilities reflect obligations to provide services for which the Company has already received consideration, and generally arise from up-front payments received in connection with Machinio's subscription services. The contract liability balance was $4.7 million as of December 31, 2021 and $4.6 million as of September 30, 2021 and is included in the line item Deferred revenue on the Condensed Consolidated Balance Sheets. Of the September 30, 2021 contract liability balance, $2.1 million was earned as Fee revenue during the three months ended December 31, 2021. Performance obligations for Machinio's subscription services are satisfied over time as the Company provides the services over the term of the subscription. At December 31, 2021, the Company has a remaining performance obligation of $4.7 million for these subscription services, and the Company expects to recognize the substantial majority of that amount as Fee Revenue over the next 12 months. Contract Costs Contract costs relate to sales commissions paid on subscription contracts that are capitalized. Contract costs are amortized over the expected life of the customer contract. The contract cost balance was $1.7 million as of December 31, 2021 and $1.6 million as of September 30, 2021 and is included in the line items Prepaid expenses and other current assets and Other assets on the Condensed Consolidated Balance Sheets. Amortization expense was $0.2 million and $0.1 million during the three months ended December 31, 2021 and 2020, respectively. Other Assets - Promissory Note On September 30, 2015, the Company sold certain assets related to its Jacobs Trading business to Tanager Acquisitions, LLC (Tanager). In connection with the disposition, Tanager assumed certain liabilities related to the Jacobs Trading business. Tanager issued a $12.3 million five-year interest-bearing promissory note to the Company. On October 10, 2019, the Company entered into a Forbearance Agreement and Amendment to Note, Security Agreement and Guaranty Agreement (the "Forbearance Agreement") with Tanager (now known as Jacobs Trading, LLC) and certain of its affiliates (collectively, "JTC"). In exchange for additional collateral, security, and a higher interest rate, the Company granted JTC a new repayment schedule that requires quarterly payments to be made from August 2020 to August 2023. Upon execution of the Forbearance Agreement, JTC repaid $2.5 million in principal, plus $0.4 million in accrued interest. As of March 31, 2021, JTC had repaid $7.7 million of the $12.3 million owed to the Company and had an outstanding principal balance of $4.6 million. On May 12, 2021, the Company entered into the First Amendment to the Forbearance Agreement with JTC, providing JTC with full satisfaction and discharge from its indebtedness upon receipt of a $3.5 million payment made on May 17, 2021. As a result, the Company recorded a $1.1 million loss as component of Other operating expenses in its Condensed Consolidated Statement of Operations during the three months ended June 30, 2021, representing the difference between the $4.6 million outstanding balance of principal and accrued interest and the $3.5 million payment received. There was no impact on the unaudited financial statements from this transaction as of and for the three months ended December 31, 2021 and December 31, 2020. Risk Associated with Certain Concentrations For the majority of buyers that receive goods before payment to the Company is made, credit evaluations are performed. However, for the remaining buyers, goods are not shipped before payment is made, and as a result the Company is not subject to significant collection risk from those buyers. For consignment sales transactions, funds are typically collected from buyers and are held by the Company on the sellers' behalf. The funds are included in Cash and cash equivalents on the Condensed Consolidated Balance Sheets. The Company releases the funds to the seller, less the Company's commission and other fees due, through Accounts payable after the buyer has accepted the goods or within 30 days, depending on the state where the buyer and seller conduct business. Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash in banks and cash equivalent money market funds in accounts which may at times exceed federally insured limits (FDIC and/or SIPC), and Accounts receivable. The Company deposits its cash and acquires cash equivalent money market funds with financial institutions that the Company considers to be of high credit quality. Additionally, the Company has multiple vendor contracts with Amazon.com, Inc. under which the Company acquires and sells commercial merchandise. The property purchased under these contracts with Amazon.com, Inc. represented 60.5% and 60.0% of consolidated Cost of goods sold for the three months ended December 31, 2021 and 2020, respectively. These contracts are included within the RSCG reportable segment. Recent Accounting Pronouncements Accounting Standards Adopted In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The Company adopted the new standard on a prospective basis effective October 1, 2021. This accounting standard has not had a material impact on the Company's condensed consolidated financial statements. Accounting Standards Not Yet Adopted In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments (Topic 326), or ASC 326. ASC 326, including all amendments and related guidance, was designed to provide financial statement users with more useful information about the expected credit losses on financial instruments and other commitments to extend credit. ASC 326 will require estimation of expected credit losses using a methodology that takes into consideration a broad range of reasonable and supportable information. The guidance will be effective for the Company beginning on October 1, 2023 and will be applied on a modified-retrospective basis, with any cumulative-effect adjustment recorded to retained earnings on the adoption date. The Company is in the process of evaluating the impact ASC 326 will have on its condensed consolidated financial statements and expects to estimate credit losses on its financial assets such as its Accounts receivable and money market funds. While the Company has not experienced significant credit losses historically, the materiality of the impact of adoption will depend on events and conditions as of the date of adoption, which cannot be determined conclusively at this time.

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and the rules and regulations of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal, recurring adjustments considered necessary for a fair presentation, have been included, and intercompany transactions and accounts have been eliminated in consolidation. The information disclosed in the notes to the condensed consolidated financial statements for these periods is unaudited. Operating results for the three months ended December 31, 2021 are not necessarily indicative of the results that may be expected for the year ending September 30, 2022 or for any future period.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect amounts in the condensed consolidated financial statements and accompanying notes. For the three months ended December 31, 2021, these estimates required the Company to make assumptions about the extent and duration of restrictions on cross-border transactions and the impact of the COVID-19 pandemic on macroeconomic conditions and, in turn, the Company's results of operations. As there remains uncertainty associated with the COVID-19 pandemic, the Company will continue to update its assumptions as conditions change. Actual results could differ significantly from those estimates.

Contract assets reflect an estimate of expenses that will be reimbursed upon settlement with a seller. The contract asset balance was $0.7 million as of December 31, 2021 and $0.6 million as of September 30, 2021 and is included in the line item Prepaid expenses and other current assets on the Condensed Consolidated Balance Sheets.

Contract liabilities reflect obligations to provide services for which the Company has already received consideration, and generally arise from up-front payments received in connection with Machinio's subscription services. The contract liability balance was $4.7 million as of December 31, 2021 and $4.6 million as of September 30, 2021 and is included in the line item Deferred revenue on the Condensed Consolidated Balance Sheets. Of the September 30, 2021 contract liability balance, $2.1 million was earned as Fee revenue during the three months ended December 31, 2021.

Performance obligations for Machinio's subscription services are satisfied over time as the Company provides the services over the term of the subscription. At December 31, 2021, the Company has a remaining performance obligation of $4.7 million for these subscription services, and the Company expects to recognize the substantial majority of that amount as Fee Revenue over the next 12 months.

Contract costs relate to sales commissions paid on subscription contracts that are capitalized. Contract costs are amortized over the expected life of the customer contract. The contract cost balance was $1.7 million as of December 31, 2021 and $1.6 million as of September 30, 2021 and is included in the line items Prepaid expenses and other current assets and Other assets on the Condensed Consolidated Balance Sheets. Amortization expense was $0.2 million and $0.1 million during the three months ended December 31, 2021 and 2020, respectively.

On September 30, 2015, the Company sold certain assets related to its Jacobs Trading business to Tanager Acquisitions, LLC (Tanager). In connection with the disposition, Tanager assumed certain liabilities related to the Jacobs Trading business. Tanager issued a $12.3 million five-year interest-bearing promissory note to the Company.

On October 10, 2019, the Company entered into a Forbearance Agreement and Amendment to Note, Security Agreement and Guaranty Agreement (the "Forbearance Agreement") with Tanager (now known as Jacobs Trading, LLC) and certain of its affiliates (collectively, "JTC"). In exchange for additional collateral, security, and a higher interest rate, the Company granted JTC a new repayment schedule that requires quarterly payments to be made from August 2020 to August 2023. Upon execution of the Forbearance Agreement, JTC repaid $2.5 million in principal, plus $0.4 million in accrued interest. As of March 31, 2021, JTC had repaid $7.7 million of the $12.3 million owed to the Company and had an outstanding principal balance of $4.6 million.

On May 12, 2021, the Company entered into the First Amendment to the Forbearance Agreement with JTC, providing JTC with full satisfaction and discharge from its indebtedness upon receipt of a $3.5 million payment made on May 17, 2021. As a result, the Company recorded a $1.1 million loss as component of Other operating expenses in its Condensed Consolidated Statement of Operations during the three months ended June 30, 2021, representing the difference between the $4.6 million outstanding balance of principal and accrued interest and the $3.5 million payment received. There was no impact on the unaudited financial statements from this transaction as of and for the three months ended December 31, 2021 and December 31, 2020.

For the majority of buyers that receive goods before payment to the Company is made, credit evaluations are performed. However, for the remaining buyers, goods are not shipped before payment is made, and as a result the Company is not subject to significant collection risk from those buyers.

For consignment sales transactions, funds are typically collected from buyers and are held by the Company on the sellers' behalf. The funds are included in Cash and cash equivalents on the Condensed Consolidated Balance Sheets. The Company releases the funds to the seller, less the Company's commission and other fees due, through Accounts payable after the buyer has accepted the goods or within 30 days, depending on the state where the buyer and seller conduct business.

Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash in banks and cash equivalent money market funds in accounts which may at times exceed federally insured limits (FDIC and/or SIPC), and Accounts receivable. The Company deposits its cash and acquires cash equivalent money market funds with financial institutions that the Company considers to be of high credit quality.

Additionally, the Company has multiple vendor contracts with Amazon.com, Inc. under which the Company acquires and sells commercial merchandise. The property purchased under these contracts with Amazon.com, Inc. represented 60.5% and 60.0% of consolidated Cost of goods sold for the three months ended December 31, 2021 and 2020, respectively. These contracts are included within the RSCG reportable segment.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The Company adopted the new standard on a prospective basis effective October 1, 2021. This accounting standard has not had a material impact on the Company's condensed consolidated financial statements.