REVENUE	6 Months Ended
REVENUE	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUE The Company recognizes revenue when performance obligations identified under the terms of contracts with its customers are satisfied. A performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer. A contract with a customer is an agreement which both parties have approved, that creates enforceable rights and obligations, has commercial substance and with respect to which payment terms are identified and collectability is probable. Once the Company has entered a contract or purchase order, it is evaluated to identify performance obligations. For each performance obligation, revenue is recognized when control of the promised products is transferred to the customer, or services are satisfied under the contract or purchase order, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those products or services (the transaction price). A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue when each performance obligation is satisfied. A majority of the Company’s contracts have a single performance obligation which represents, in most cases, the product being sold to the customer. To a lesser extent, some contracts include multiple performance obligations such as a product, the related installation, and extended warranty services. These contracts require judgment in determining the number of performance obligations. Over 80% of the Company’s performance obligations are recognized at a point in time that relates to the manufacture and sale of a broad range of products and components within the CPP and HBP segments, and revenue is recognized when title, and risk and rewards of ownership, have transferred to the customer. A majority of CPP and HBP segment revenue is short cycle in nature with shipments occurring within one year from order and does not include a material long-term financing component, implicitly or explicitly. Less than 20% of the Company’s performance obligations are recognized over time or under the percentage-of-completion method; these relate to prime or subcontractors from contract awards with the U.S. Government, as well as foreign governments and other commercial customers within our DE segment. These contracts are typically long-term in nature, usually greater than one year and do not include a material long-term financing component, either implicitly or explicitly. Revenue and profits from such contracts are recognized under the percentage-of-completion (over time) method of accounting. Revenue and profits on fixed-price contracts that contain engineering as well as production requirements are recorded based on the ratio of total actual incurred costs to date to the total estimated costs for each contract (cost-to-cost method). Sales recognized over time are generally accounted for using an input measure to determine progress completed at the end of the period. Adjustments to estimates for a contract's estimated costs at completion and estimated profit or loss are often required as experience is gained, more information is obtained (even though the scope of work required under the contract may or may not change) and contract modifications occur. The impact of such adjustments to estimates is made on a cumulative basis in the period when such information has become known. For the three and six months ended March 31, 2020, income from operations included net unfavorable catch up adjustments approximating $2,224 and $5,243, respectively. Gross profit is impacted by a variety of factors, including the mix of products, systems and services, production efficiencies, price competition and general economic conditions. We believe that cumulative costs incurred to date as a percentage of estimated total contract costs at completion is an appropriate measure of progress towards satisfaction of performance obligations, as it most accurately depicts the progress of our work and transfer of control to our customers. For contracts in which anticipated total costs exceed the total expected revenue, an estimated loss is recognized in the period when identifiable. A provision for the entire amount of the estimated loss is recorded on a cumulative basis, and is recorded as a reduction to gross margin on the Consolidated Statements of Operations and Comprehensive Income (Loss). The provision had an immaterial impact on Griffon's Consolidated Financial Statements. The estimated remaining costs to complete loss contracts as of March 31, 2020 and September 30, 2019 were approximately $8,560 and $9,790, respectively. For a complete explanation of Griffon’s revenue accounting policies, this note should be read in conjunction with Griffon’s Annual Report on Form 10-K for the year ended September 30, 2019. See Note 12 - Business Segments for revenue from contracts with customers disaggregated by end markets, segments and geographic location. Transaction Price Allocated to the Remaining Performance Obligations On March 31, 2020, we had $331,740 of remaining performance obligations, which we also refer to as total backlog. We expect to recognize approximately 73% of our remaining performance obligations as revenue within one year, with the balance to be completed thereafter. Backlog represents the dollar value of funded orders for which work has not been performed. Backlog generally increases with bookings, and converts into revenue as we incur costs related to contractual commitments or the shipment of product. Given the nature of our business and a larger dependency on international customers, our bookings, and therefore our backlog, is impacted by the longer maturation cycles resulting in delays in the timing and amounts of such awards, which are subject to numerous factors, including fiscal constraints placed on customer budgets; political uncertainty; the timing of customer negotiations; and the timing of governmental approvals. Contract Balances Contract assets were $94,495 as of March 31, 2020 compared to $105,111 as of September 30, 2019. The $10,616 decrease in our contract assets balance was primarily due to the timing of billings and work performed on various radar and surveillance programs. Contract assets primarily relate to the Company's right to consideration for work completed but not billed at the reporting date and are recorded in Contract costs and recognized income not yet billed, net of progress payments in the Consolidated Balance Sheets. Contract assets are transferred to receivables when the right to consideration becomes unconditional. Contract costs and recognized income not yet billed consists of amounts accounted for under the percentage of completion method of accounting, recoverable costs and accrued profit that cannot yet be invoiced under the terms of certain long-term contracts. Amounts will be invoiced when applicable contract terms, such as the achievement of specified milestones or product delivery, are met. At March 31, 2020 and September 30, 2019, approximately $12,612 and $13,100, respectively, of contract costs and recognized income not yet billed were expected to be collected after one year. As of March 31, 2020, Contract costs and recognized income not yet billed included approximately $1,570 of reserves for contract risk. As of September 30, 2019, Contract costs and recognized income not yet billed included no reserves for contract risk. Contract liabilities were $21,292 as of March 31, 2020 compared to $26,259 as of September 30, 2019. The $4,967 decrease in the contract liabilities balance was due to the recognition of revenue primarily from surveillance and airborne maritime surveillance radar programs. Contract liabilities relate to advance consideration received from customers for which revenue has not been recognized. The Company often receives cash payments from customers in advance of the Company’s performance resulting in contract liabilities. These contract liabilities are classified as current on the Consolidated Balance Sheets based on the timing of when the Company expects to recognize revenue. Current contract liabilities are recorded in Accounts payable on the Consolidated Balance Sheets. Contract liabilities are reduced when the associated revenue from the contract is recognized.