General	9 Months Ended
General	Sep. 30, 2020
Basis of Presentation and Significant Accounting Policies [Abstract]
General	General Basis of Presentation The accompanying unaudited consolidated financial statements of AAON, Inc., a Nevada corporation, and our operating subsidiaries, all of which are wholly-owned, (collectively, the “Company”) have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and with the rules and regulations of the Securities and Exchange Commission (“SEC”). Our financial statements consolidate all of our affiliated entities in which we have a controlling financial interest. Because we hold certain rights that give us the power to direct the activities of two variable interest entities ("VIEs") (Note 16) that most significantly impact the VIEs economic performance, combined with a variable interest that gives us the right to receive potentially significant benefits or the obligation to absorb potentially significant losses, we have a controlling financial interest in those VIEs. These financial statements have not been audited by the Company's independent registered public accounting firm, except that the consolidated balance sheet at December 31, 2019 is derived from audited consolidated financial statements. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The financial statements reflect all adjustments (all of which are of a normal recurring nature) which are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. Interim results are not necessarily indicative of the results that may be expected for a full year. Certain disclosures have been condensed in or omitted from these consolidated financial statements. The accompanying unaudited financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019. All intercompany balances and transactions have been eliminated in consolidation. We are engaged in the engineering, manufacturing, marketing and sale of air conditioning and heating equipment consisting of standard, semi-custom and custom rooftop units, chillers, packaged outdoor mechanical rooms, air handling units, makeup air units, energy recovery units, condensing units, geothermal/water-source heat pumps, coils and controls. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Because these estimates and assumptions require significant judgment, actual results could differ from those estimates and could have a significant impact on our results of operations, financial position and cash flows. We reevaluate our estimates and assumptions as needed, but at a minimum on a quarterly basis. The most significant estimates include, but are not limited to, inventory reserves, warranty accrual, worker's compensation accrual, medical insurance accrual, income taxes and share-based compensation. Actual results could differ materially from those estimates. Impact of COVID-19 Pandemic In March 2020, the World Health Organization characterized the coronavirus ("COVID-19") a pandemic, and the President of the United States declared the COVID-19 outbreak a national emergency. The rapid spread of the pandemic and the continuously evolving responses to combat it have had an increasingly negative impact on the global economy. Our manufacturing operations are considered a critical infrastructure industry, as defined by the U.S. Department of Homeland Security, as such, the decrees issued by national, state, and local governments in response to the COVID-19 pandemic have had minimal impact on our operations except for higher employee absenteeism in our manufacturing facilities. We had continuous operations during the nine months ended September 30, 2020. For the most part, our workers are able to socially distance themselves during the manufacturing process. Additional precautions have been taken to social distance workers that work in close environments. The Company utilizes sanitation stations, requires the use of a facial covering when unable to socially distance, performs daily temperature scanning, and performs additional cleaning and sanitation throughout the day and deep cleaning overnight. The Company did see significant employee absenteeism in the latter part of June 2020. These unexpected employee absences resulted in reduced shipments and longer lead times in the second quarter 2020. During the third quarter 2020, employee attendance levels were stronger than previously anticipated. Additionally, our work force has adapted well to school and childcare related issues. The magnitude of the impact of COVID-19 remains unpredictable and we, therefore, continue to anticipate potential supply chain disruptions, increased employee absenteeism and additional health and safety costs related to the COVID-19 pandemic that could unfavorably impact our business. Although these disruptions and costs are expected to be temporary, there is significant uncertainty around the duration and overall impact to our business operations. We do not believe that the impact of the COVID-19 pandemic will have a material adverse effect on the results of our operations, financial position and cash flows as of and for the year ended December 31, 2020. However, we are monitoring the progression of the pandemic and its potential effect on our financial position, results of operations and cash flows. Accounting Policies A comprehensive discussion of our critical accounting policies and management estimates is included in Management’s Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2019. Fair Value Measurements We adopted ASU No. 2018-13, Fair Value Measurements (Topic 820), as amended, as of January 1, 2020. The ASU includes additional disclosure requirements for unrealized gains and losses for Level 3 fair value measurements and significant observable inputs used to develop Level 3 fair value measurements. There was not a material impact to financial statements upon adoption. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. Fair value is based upon assumptions that market participants would use when pricing an asset or liability. We use the following fair value hierarchy, which prioritizes valuation technique inputs used to measure fair value into three broad levels: •Level 1: Quoted prices in active markets for identical assets and liabilities that we have the ability to access at the measurement date. •Level 2: Inputs (other than quoted prices included within Level 1) that are either directly or indirectly observable for the asset or liability, including (i) quoted prices for similar assets or liabilities in active markets, (ii) quoted prices for identical or similar assets or liabilities in inactive markets, (iii) inputs other than quoted prices that are observable for the asset or liability, and (iv) inputs that are derived from observable market data by correlation or other means. •Level 3: Unobservable inputs for the asset or liability including situations where there is little, if any, market activity for the asset or liability. Items categorized in Level 3 include the estimated fair values of property, plant and equipment, intangible assets and goodwill acquired in a business combination. The fair value hierarchy gives the highest priority to quoted prices in active markets (Level 1) and the lowest priority to unobservable inputs (Level 3). In some cases, the inputs used to measure fair value might fall into different levels of the fair value hierarchy. The lowest level input that is significant to a fair value measurement determines the applicable level in the fair value hierarchy. Assessing the significance of a particular input to a fair value measurement requires judgment, considering factors specific to the asset or liability. Intangible Assets Our intangible assets include various trademarks, service marks and technical knowledge acquired in our February 2018 business combination. We amortize our intangible assets on a straight-line basis over the estimated useful lives of the assets. We evaluate the carrying value of our amortizable intangible assets for potential impairment when events and circumstances warrant such a review. Goodwill Goodwill represents the excess of the consideration paid for the acquired businesses, in our February 2018 business combination, over the fair value of the individual assets acquired, net of liabilities assumed. Goodwill at September 30, 2020 is deductible for income tax purposes. Goodwill is not amortized, but instead is evaluated for impairment at least annually. We perform our annual assessment of impairment during the fourth quarter of our fiscal year, and more frequently if circumstances warrant. Recent Accounting Pronouncements Changes to U.S. GAAP are established by the Financial Accounting Standards Board ("FASB") in the form of Accounting Standards Updates ("ASUs") to the FASB's Accounting Standards Codification ("ASC"). We consider the applicability and impact of all ASUs. ASUs not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on our consolidated financial statements and notes thereto. In December 2019, the FASB issued ASU 2019-12, Income Taxes: Simplifying the Accounting for Income Taxes. The ASU includes simplification of accounting for income taxes for franchise taxes, step up in tax basis for goodwill as part of a business combination and interim reporting of enacted changes in tax laws. The ASU is effective for the Company beginning after December 15, 2020. We do not expect ASU 2019-12 will have a material effect on our consolidated financial statements and notes thereto.