Summary of Significant Accounting Policies	12 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Organization and basis of presentation The consolidated financial statements include the accounts of ADDvantage Technologies Group, Inc. and its subsidiaries, all of which are wholly owned (collectively, the “Company”). Intercompany balances and transactions have been eliminated in consolidation. The Company’s reportable segments are Wireless Infrastructure Services (“Wireless”) and Telecommunications (“Telco”). Reclassifications Certain prior year amounts have been reclassified to conform with the current year's presentation. These reclassifications had no effect on previously reported results of operations or retained earnings. Cash, cash equivalents and restricted cash Cash and cash equivalents include demand and time deposits, money market funds and other marketable securities with maturities of three months or less when acquired. Restricted cash consists of cash held by a third-party financial institution as a reserve in connection with an agreement to sell certain receivables with recourse in the Wireless segment, see Note 3 - Accounts Receivable Agreements. Revenue recognition The Company recognizes revenue at the time a good or service is transferred to a customer and the customer, obtains control of that good or receives the service performed. Most of the Company’s sales arrangements with customers are short-term in nature involving single performance obligations related to the delivery of goods or repair of equipment and generally provide for transfer of control at the time of shipment to the customer. The Company generally permits returns of product or repaired equipment due to defects, historically, returns have not been significant. Additionally, the Company provides services related to the installation and upgrade of technology on cell sites and the construction of new small cells for 5G technology. The work under the purchase orders for wireless infrastructure services are generally completed in less than a month. These services generally consist of a single performance obligation which the Company recognizes as revenue over time. The Company uses an input method based upon a ratio of direct costs incurred to date compared to management’s estimate of the total direct costs to be incurred on each contract, since it best depicts the transfer of control to the customer. The Company’s principal sales are from Wireless services, sales of Telco equipment and Telco recycled equipment. The Company’s customers include wireless carriers, wireless equipment providers, multiple system operators, resellers and direct sales to end-user customers. The timing of revenue recognition from the wireless segment results in contract assets and contract liabilities. Generally, billing occurs subsequent to revenue recognition, resulting in contract assets. However, the Company sometimes receives advances or deposits from customers before revenue is recognized, resulting in contract liabilities. Contract assets and contract liabilities are included in Unbilled revenue and Deferred revenue, respectively, on the consolidated balance sheets. Accounts receivable Trade receivables are carried at original invoice amount less an estimate made for doubtful accounts. Management determines the allowance for doubtful accounts by regularly evaluating individual customer receivables and considering a customer’s financial condition, credit history and current economic conditions. Trade receivables are written off against the allowance when deemed uncollectible. Recoveries of trade receivables previously written off are recorded when received. The Company generally does not charge interest on past due accounts. For the Company’s Wireless segment, the Company has entered into various agreements, one with recourse, to sell certain receivables to unrelated third-party financial institutions. The other agreements without recourse are under programs offered by certain customers of the Wireless segment. The Company accounts for these transactions in accordance with Accounting Standards Codification (“ASC”) 860, “Transfers and Servicing” (“ASC 860”). ASC 860 allows for the ownership transfer of accounts receivable to qualify for sale treatment when the appropriate criteria is met, which permits the Company to present the balances sold under the program to be excluded from accounts receivable, net on the consolidated balance sheets. Receivables are considered sold when they are transferred beyond the reach of the Company and its creditors, the purchaser has the right to pledge or exchange the receivables and the Company has surrendered control over the transferred receivables. The Company records a recourse obligation if it determines that any portion of the sold receivables with recourse are uncollectible. Inventories For the Telco segment, inventories consist of new, refurbished and used telecommunications equipment. Inventory is stated at the lower of cost or net realizable value. Cost is determined using the weighted-average method. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. For the Telco segment, the Company records an inventory reserve provision to reflect inventory at its estimated net realizable value based on a review of inventory quantities on hand, historical sales volumes and technology changes. These reserves are to provide for items that are potentially slow-moving, excess or obsolete. Leases The Company determines if an arrangement is a lease at inception of the arrangement. To the extent that we determine an arrangement represents a lease, we classify that lease as either a right-of-use ("ROU") lease or a finance lease. We capitalize ROU leases on our consolidated balance sheets through a ROU asset and a corresponding ROU lease liability. ROU assets represent our right to use an underlying asset for the lease term and ROU lease liabilities represent our obligation to make lease payments arising from the lease. ROU leases are included in long-term assets and ROU lease liabilities are classified as either current or long-term liabilities in our consolidated balance sheets. ROU assets and liabilities are recognized at the commencement date of an arrangement based on the present value of lease payments over the lease term. Lease expense for ROU lease payments is recognized on a straight-line basis over the lease term. Property and equipment Property and equipment consist of software, office equipment, wireless services equipment and warehouse and service equipment with estimated useful lives generally of 3 years, 5 years, 7 years, and 10 years, respectively. The wireless services equipment includes mobile wireless temporary towers, equipment trailers and construction equipment. Depreciation is provided using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the useful lives or the remainder of the lease agreement. Gains or losses from the ordinary sale or retirement of property and equipment are recorded and included in operating expense. Repairs and maintenance costs are generally expensed as incurred, whereas major improvements are capitalized. Depreciation expense was $0.9 million in each of the years ended September 30, 2021 and 2020. Goodwill Goodwill represents the excess of purchase price of acquisitions over the acquisition date fair value of the net assets of businesses acquired. Goodwill is not amortized and is tested at least annually for impairment. The Company performs its annual analysis during the fourth quarter of each fiscal year and in any other period in which indicators of impairment warrant additional analysis. Goodwill is evaluated for impairment by comparing the estimate of the fair value of each reporting unit, or operating segment, with the reporting unit’s carrying value, including goodwill. The reporting units for purposes of the goodwill impairment calculation are aggregated into the Wireless segment and ADDvantage Triton LLC (Triton) operating segment, and Nave Communications Company (Nave) operating segment. Management utilizes a discounted cash flow analysis to determine the estimated fair value of each reporting unit. Significant judgments and assumptions including the discount rate, anticipated revenue growth rate, gross margins and operating expenses are inherent in these fair value estimates. As a result, actual results may differ from the estimates utilized in the discounted cash flow analysis. The use of alternate judgments and/or assumptions could result in the recognition of different levels of impairment charges in the financial statements. During the year ended September 30, 2020, due to operating losses and uncertainties surrounding the impact of the COVID-19 pandemic on the overall economy and the resulting impact on the capital budgets of both Customers and our Company, we determined that impairment indicators were present. The Company performed a valuation using a discounted cash flow analysis for the Nave and Triton operating segments to determine if the fair value exceeded their respective carrying values. For both Nave and Triton, the fair value for each was less than their respective carrying values. Therefore, the Company recorded an impairment charge of $4.8 million as of March 31, 2020, which fully impaired goodwill for both operating segments in the Telco segment. Although the Company does not anticipate a future impairment charge, certain events could occur that might adversely affect the reported value of the remaining goodwill in the Wireless segment, which was $0.1 million at September 30, 2021. Intangible assets Intangible assets consist of customer relationships, trade names, and intellectual property. Intangibles assets that have finite useful lives are amortized on a straight-line basis over their estimated useful lives ranging from 3 years to 10 years. Impairment of long-lived assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10-15, “Impairment or Disposal of Long-Lived Assets.” ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals. Income taxes The Company provides for income taxes in accordance with the liability method of accounting. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis and tax carryforward amounts. Management provides a valuation allowance against deferred tax assets for amounts which are not considered “more likely than not” to be realized. Advertising costs Advertising costs are expensed as incurred. Advertising expense was $0.4 million and $0.5 million for the years ended September 30, 2021 and 2020, respectively. Management estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Any significant, unanticipated changes in product demand, technological developments or continued economic trends affecting the wireless infrastructure or telecommunications industries could have a significant impact on the value of the Company's inventory and operating results. Concentrations of risk The Company holds cash with one major financial institution, which at times exceeds FDIC insured limits. Historically, the Company has not experienced any losses due to such concentration of credit risk. Other financial instruments that potentially subject the Company to concentration of credit risk consist principally of trade receivables. Concentrations of credit risk with respect to trade receivables are limited because a large number of geographically diverse customers make up the Company’s customer base, thus spreading the trade credit risk. As of September 30, 2021, one Telco customer accounted for 31% of accounts receivable, and one Wireless customer accounted for 28% of accounts receivable. The Company controls credit risk through credit approvals, credit limits and monitoring procedures. The Company performs credit evaluations for all new customers but does not require collateral to support customer receivables. Share-based compensation ADDvantage compensates our directors and executives using time-based stock options and restricted shares awards (RSA's). ADDvantage accounts for share-based payment awards under ASC 718 - Compensation - Stock Compensation (ASC 718), which requires that the value of the award is established at the date of the grant and is expensed over the vesting period of the grant. The method of determining the fair value of share-based payments depends on the type of award. Share-based awards that vest over a certain service period with no market conditions are valued at the closing market price on the grant date. Option grants are valued using the Black-Scholes-Merton model using model inputs that are determined on the date of the grant. Once the per-share fair value on the grant date is established, the aggregate expense of the grant is recognized on a graded vesting basis over the vesting period of the grant. Fair value of financial instruments The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, accrued expenses and other current liabilities approximate fair value due to their short maturities. The carrying value of the Company’s variable-rate line of credit approximates its fair value since the interest rate fluctuates periodically based on a floating interest rate. Retirement Plan The Company sponsors a 401(k) plan that allows participation by all employees who are at least 21 years of age and have completed over 60 days of service. The Company's contributions to the plan consist of a matching contribution as determined by the plan document. Costs recognized under the 401(k) plan were $0.2 million and, $0.1 million for the years ended September 30, 2021 and September 30, 2020, respectively, after temporarily suspending matching contributions during 2020. Recently issued accounting standards In June 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-13: “Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments.” This ASU requires entities to measure all expected credit losses for most financial assets held at the reporting date based on an expected loss model which includes historical experience, current conditions, and reasonable and supportable forecasts. Upon adoption, entities will use forward-looking information to better form their credit loss estimates. This ASU also requires enhanced disclosures to help financial statement users better understand significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an entity’s portfolio. On November 15, 2019, the FASB delayed the effective date of the standard for companies that qualify under smaller reporting company reporting rules. As amended, the effective date of ASC Topic 326 was delayed until fiscal years beginning after December 15, 2022 for SEC filers that are eligible to be smaller reporting companies under the Securities and Exchange Commission definition. We are currently in the process of evaluating this new standard update, however we do not anticipate the adoption will have a material impact on our results.

The consolidated financial statements include the accounts of ADDvantage Technologies Group, Inc. and its subsidiaries, all of which are wholly owned (collectively, the “Company”). Intercompany balances and transactions have been eliminated in consolidation. The Company’s reportable segments are Wireless Infrastructure Services (“Wireless”) and Telecommunications (“Telco”).

Cash and cash equivalents include demand and time deposits, money market funds and other marketable securities with maturities of three months or less when acquired. Restricted cash consists of cash held by a third-party financial institution as a reserve in connection with an agreement to sell certain receivables with recourse in the Wireless segment, see Note 3 - Accounts Receivable Agreements.

The Company recognizes revenue at the time a good or service is transferred to a customer and the customer, obtains control of that good or receives the service performed. Most of the Company’s sales arrangements with customers are short-term in nature involving single performance obligations related to the delivery of goods or repair of equipment and generally provide for transfer of control at the time of shipment to the customer. The Company generally permits returns of product or repaired equipment due to defects, historically, returns have not been significant.

Additionally, the Company provides services related to the installation and upgrade of technology on cell sites and the construction of new small cells for 5G technology. The work under the purchase orders for wireless infrastructure services are generally completed in less than a month. These services generally consist of a single performance obligation which the Company recognizes as revenue over time. The Company uses an input method based upon a ratio of direct costs incurred to date compared to management’s estimate of the total direct costs to be incurred on each contract, since it best depicts the transfer of control to the customer. The Company’s principal sales are from Wireless services, sales of Telco equipment and Telco recycled equipment. The Company’s customers include wireless carriers, wireless equipment providers, multiple system operators, resellers and direct sales to end-user customers.

The timing of revenue recognition from the wireless segment results in contract assets and contract liabilities. Generally, billing occurs subsequent to revenue recognition, resulting in contract assets. However, the Company sometimes receives advances or deposits from customers before revenue is recognized, resulting in contract liabilities. Contract assets and contract liabilities are included in Unbilled revenue and Deferred revenue, respectively, on the consolidated balance sheets.

Trade receivables are carried at original invoice amount less an estimate made for doubtful accounts. Management determines the allowance for doubtful accounts by regularly evaluating individual customer receivables and considering a customer’s financial condition, credit history and current economic conditions. Trade receivables are written off against the allowance when deemed uncollectible. Recoveries of trade receivables previously written off are recorded when received. The Company generally does not charge interest on past due accounts.

For the Company’s Wireless segment, the Company has entered into various agreements, one with recourse, to sell certain receivables to unrelated third-party financial institutions. The other agreements without recourse are under programs offered by certain customers of the Wireless segment. The Company accounts for these transactions in accordance with Accounting Standards Codification (“ASC”) 860, “Transfers and Servicing” (“ASC 860”). ASC 860

allows for the ownership transfer of accounts receivable to qualify for sale treatment when the appropriate criteria is met, which permits the Company to present the balances sold under the program to be excluded from accounts receivable, net on the consolidated balance sheets. Receivables are considered sold when they are transferred beyond the reach of the Company and its creditors, the purchaser has the right to pledge or exchange the receivables and the Company has surrendered control over the transferred receivables. The Company records a recourse obligation if it determines that any portion of the sold receivables with recourse are uncollectible.

For the Telco segment, inventories consist of new, refurbished and used telecommunications equipment. Inventory is stated at the lower of cost or net realizable value. Cost is determined using the weighted-average method. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. For the Telco segment, the Company records an inventory reserve provision to reflect inventory at its estimated net realizable value based on a review of inventory quantities on hand, historical sales volumes and technology changes. These reserves are to provide for items that are potentially slow-moving, excess or obsolete.

The Company determines if an arrangement is a lease at inception of the arrangement. To the extent that we determine an arrangement represents a lease, we classify that lease as either a right-of-use ("ROU") lease or a finance lease. We capitalize ROU leases on our consolidated balance sheets through a ROU asset and a corresponding ROU lease liability. ROU assets represent our right to use an underlying asset for the lease term and ROU lease liabilities represent our obligation to make lease payments arising from the lease.

ROU leases are included in long-term assets and ROU lease liabilities are classified as either current or long-term liabilities in our consolidated balance sheets. ROU assets and liabilities are recognized at the commencement date of an arrangement based on the present value of lease payments over the lease term. Lease expense for ROU lease payments is recognized on a straight-line basis over the lease term.

Property and equipment consist of software, office equipment, wireless services equipment and warehouse and service equipment with estimated useful lives generally of 3 years, 5 years, 7 years, and 10 years, respectively. The wireless services equipment includes mobile wireless temporary towers, equipment trailers and construction equipment. Depreciation is provided using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the useful lives or the remainder of the lease agreement. Gains or losses from the ordinary sale or retirement of property and equipment are recorded and included in operating expense. Repairs and maintenance costs are generally expensed as incurred, whereas major improvements are capitalized. Depreciation expense was $0.9 million in each of the years ended September 30, 2021 and 2020.

Goodwill represents the excess of purchase price of acquisitions over the acquisition date fair value of the net assets of businesses acquired. Goodwill is not amortized and is tested at least annually for impairment. The Company performs its annual analysis during the fourth quarter of each fiscal year and in any other period in which indicators of impairment warrant additional analysis. Goodwill is evaluated for impairment by comparing the estimate of the fair value of each reporting unit, or operating segment, with the reporting unit’s carrying value, including goodwill. The reporting units for purposes of the goodwill impairment calculation are aggregated into the Wireless segment and ADDvantage Triton LLC (Triton) operating segment, and Nave Communications Company (Nave) operating segment.

Management utilizes a discounted cash flow analysis to determine the estimated fair value of each reporting unit. Significant judgments and assumptions including the discount rate, anticipated revenue growth rate, gross margins and operating expenses are inherent in these fair value estimates. As a result, actual results may differ from the estimates utilized in the discounted cash flow analysis. The use of alternate judgments and/or assumptions could result in the recognition of different levels of impairment charges in the financial statements.

During the year ended September 30, 2020, due to operating losses and uncertainties surrounding the impact of the COVID-19 pandemic on the overall economy and the resulting impact on the capital budgets of both Customers and our Company, we determined that impairment indicators were present. The Company performed a valuation using a discounted cash flow analysis for the Nave and Triton operating segments to determine if the fair value exceeded their respective carrying values. For both Nave and Triton, the fair value for each was less than their respective carrying values. Therefore, the Company recorded an impairment charge of $4.8 million as of March 31, 2020, which fully impaired goodwill for both operating segments in the Telco segment. Although the Company does not anticipate a future impairment charge, certain events could occur that might adversely affect the reported value of the remaining goodwill in the Wireless segment, which was $0.1 million at September 30, 2021.

The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10-15, “Impairment or Disposal of Long-Lived Assets.” ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals.

The Company provides for income taxes in accordance with the liability method of accounting. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis and tax carryforward amounts. Management provides a valuation allowance against deferred tax assets for amounts which are not considered “more likely than not” to be realized.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.

Any significant, unanticipated changes in product demand, technological developments or continued economic trends affecting the wireless infrastructure or telecommunications industries could have a significant impact on the value of the Company's inventory and operating results.

Other financial instruments that potentially subject the Company to concentration of credit risk consist principally of trade receivables. Concentrations of credit risk with respect to trade receivables are limited because a large number of geographically diverse customers make up the Company’s customer base, thus spreading the trade credit risk. As of September 30, 2021, one Telco customer accounted for 31% of accounts receivable, and one Wireless

customer accounted for 28% of accounts receivable. The Company controls credit risk through credit approvals, credit limits and monitoring procedures. The Company performs credit evaluations for all new customers but does not require collateral to support customer receivables.

ADDvantage compensates our directors and executives using time-based stock options and restricted shares awards (RSA's). ADDvantage accounts for share-based payment awards under ASC 718 - Compensation - Stock Compensation (ASC 718), which requires that the value of the award is established at the date of the grant and is expensed over the vesting period of the grant. The method of determining the fair value of share-based payments depends on the type of award. Share-based awards that vest over a certain service period with no market conditions are valued at the closing market price on the grant date. Option grants are valued using the Black-Scholes-Merton model using model inputs that are determined on the date of the grant. Once the per-share fair value on the grant date is established, the aggregate expense of the grant is recognized on a graded vesting basis over the vesting period of the grant.

The Company sponsors a 401(k) plan that allows participation by all employees who are at least 21 years of age and have completed over 60 days of service. The Company's contributions to the plan consist of a matching contribution as determined by the plan document. Costs recognized under the 401(k) plan were $0.2 million and, $0.1 million for the years ended September 30, 2021 and September 30, 2020, respectively, after temporarily suspending matching contributions during 2020.

In June 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-13: “Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments.” This ASU requires entities to measure all expected credit losses for most financial assets held at the reporting date based on an expected loss model which includes historical experience, current conditions, and reasonable and supportable forecasts. Upon adoption, entities will use forward-looking information to better form their credit loss estimates. This ASU also requires enhanced disclosures to help financial statement users better understand significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an entity’s portfolio. On November 15, 2019, the FASB delayed the effective date of the standard for companies that qualify under smaller reporting company reporting rules. As amended, the effective date of ASC Topic 326 was delayed until fiscal years beginning after December 15, 2022 for SEC filers that are eligible to be smaller reporting companies under the Securities and Exchange Commission definition. We are currently in the process of evaluating this new standard update, however we do not anticipate the adoption will have a material impact on our results.