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SIGNIFICANT ACCOUNTING POLICIES (Policies) | 12 Months Ended
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Dec. 31, 2020
Accounting Policies [Abstract] |
Principles of Consolidation | Principles of ConsolidationThe accompanying consolidated financial statements include the accounts of Clean Harbors, Inc. and its majority-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates | Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions, which are evaluated on an ongoing basis, that affect the amounts reported in the Company's consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and on various other assumptions it believes to be reasonable at the time under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and disclosure, if any, of contingent assets and liabilities and reported amounts of revenues and expenses. Actual results could differ from those estimates and judgments.
Reclassifications | Reclassifications Certain prior year amounts have been reclassified to conform to the current year presentation. These reclassifications have no impact on previously reported subtotals.
Cash, Cash Equivalents and Uncashed Checks | Cash, Cash Equivalents and Uncashed Checks Cash consists primarily of cash on deposit and money market accounts. Marketable securities with maturities of three months or less from the date of purchase are classified as cash equivalents. The Company's cash management program with its revolving credit lender allows for the maintenance of a zero balance in the U.S. bank disbursement accounts that are used to issue vendor and payroll checks. When checks are presented to the bank for payment, cash deposits in amounts sufficient to fund the checks are made, at the Company's discretion, either from funds provided by other accounts or under the terms of the Company's revolving credit facility. Checks that have been written to vendors or employees but have not yet been presented for payment at the Company's bank are classified as uncashed checks as part of accounts payable and changes in the balance are reported as a financing activity in the consolidated statements of cash flows.
Marketable Securities | Marketable Securities The Company, through its wholly-owned captive insurance subsidiary, invests in marketable securities consisting of U.S. Treasury securities, corporate notes and bonds and commercial paper. As of December 31, 2020 and 2019, the Company had total marketable securities and cash equivalents as follows (in thousands):
| December 31, 2020 |  | December 31, 2019
Commercial paper | $ | — |  |  | $ | 2,395 |
Total cash equivalents | — |  |  | 2,395 |
U.S. Treasury securities | 28,901 |  |  | 12,406 |
Corporate notes and bonds | 22,956 |  |  | 26,678 |
Commercial paper | — |  |  | 3,337 |
Total marketable securities | 51,857 |  |  | 42,421 |
Total | $ | 51,857 |  |  | $ | 44,816 |
Realized gains and losses on sales of available-for-sale marketable securities in the years presented were immaterial. The majority of the marketable securities have a remaining maturity of less than one year and fair value approximates cost.
Allowances for Doubtful Accounts | Allowances for Doubtful Accounts On a regular basis, the Company evaluates its accounts receivable and establishes the allowance for doubtful accounts based on an evaluation of certain criteria and evidence of collection certainty including historical collection trends, reasonable expectations of future collections, current economic trends and changes in customer payment patterns. Past-due receivable balances are written off when the Company's internal collection efforts have been deemed unsuccessful in collecting the outstanding balance due.
Credit Concentration | Credit Concentration Concentration of credit risks in accounts receivable is limited due to the large number of customers comprising the Company's customer base throughout North America. The Company maintains policies over credit extension that include credit evaluations, credit limits and collection monitoring procedures on a customer-by-customer basis. However, the Company generally does not require collateral before services are performed. No individual customer accounted for more than 10% of accounts receivable or more than 10% of total direct revenues in the periods presented.
Inventories and Supplies | Inventories and Supplies Inventories are stated at the lower of cost or market. The cost of oil and oil products is principally determined on a first-in, first-out ("FIFO") basis. The cost of supplies and drums, solvent and solution and other inventories is determined on a FIFO basis. The Company continually reviews its inventories for obsolete or unsalable items and adjusts its carrying value to reflect estimated realizable values.
Property, Plant and Equipment, net (excluding landfill assets and finance lease right of use assets) | Property, Plant and Equipment, net (excluding landfill assets and finance lease right of use assets) Property, plant and equipment, net is stated at cost less accumulated depreciation. Expenditures for major renewals and improvements which extend the life or usefulness of the asset are capitalized. Items of an ordinary repair or maintenance nature are charged directly to operating expense as incurred. Gains and losses on the sale of property, plant and equipment are included in other (expense) income, net. During the construction and development period of an asset, the costs incurred are classified as construction-in-progress. When the asset is ready for its intended use, the asset is reclassified to an appropriate asset classification and depreciation or amortization commences. The Company depreciates and amortizes the capitalized cost of these assets, using the straight-line method as follows:
Asset Classification |  | Estimated Useful Life
Buildings and building improvements |  |
Buildings |  | 20-42 years
Leasehold and building improvements |  | 2-45 years
Camp and lodging equipment |  | 8-15 years
Vehicles |  | 2-15 years
Equipment |  |
Capitalized software and computer equipment |  | 3-5 years
Containers and railcars |  | 8-16 years
All other equipment |  | 4-30 years
Furniture and fixtures |  | 5-8 years
The Company tests asset groups for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. An impairment in the carrying value of long-lived assets is recognized if the expected future undiscounted cash flows derived from the assets, or group of assets, are less than their carrying value. The Company did not record any impairment charges related to long-lived assets in the periods presented.
Goodwill | Goodwill Goodwill is comprised of the purchase price of business acquisitions in excess of the fair value of the net assets acquired. Goodwill is reviewed for impairment annually as of December 31, or when events or circumstances indicate that the carrying value of the reporting unit may exceed its fair value. If the carrying value of a reporting unit exceeds the fair value, an impairment loss will be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. The Company did not recognize any impairment losses in any of the periods presented. See Note 7, "Goodwill and Other Intangible Assets," for additional information related to the Company's goodwill impairment tests.
Permits and other intangibles | Permits and Other Intangibles Costs related to acquiring licenses, permits and intangible assets, such as legal fees, site surveys, engineering costs and other expenditures are capitalized. Other intangible assets consist primarily of customer and supplier relationships, trademarks and trade names and non-compete agreements. Permits relating to landfills are amortized on a units-of-consumption basis. All other permits are amortized over periods ranging from five to 30 years on a straight-line basis. Finite-lived intangible assets are amortized on a straight-line basis over their respective useful lives, which range from five to 20 years. All finite-lived intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. When such factors and circumstances exist, management compares the projected undiscounted future cash flows associated with the related asset or group of assets to the carrying amount. The impairment loss, if any, is measured as the excess of the carrying amount over the fair value of the asset or group of assets. Indefinite-lived intangible assets are not amortized but are reviewed for impairment annually as of December 31, or when events or changes in the business environment indicate that the carrying value may be impaired. If the fair value of the asset is less than the carrying amount, the impairment loss is measured as the excess of the carrying value of the asset over its fair value.
Landfill Accounting | Landfill Accounting The Company amortizes landfill improvements and certain landfill-related permits over the estimated useful lives. The units-of-consumption method is used to amortize land, landfill cell construction, asset retirement costs and remaining landfill cells and sites. The Company also utilizes the units-of-consumption method to record closure and post-closure obligations for landfill cells and sites. Under the units-of-consumption method, the Company includes future estimated construction and asset retirement costs, as well as costs incurred to date, in the amortization base of the landfill assets. Additionally, where appropriate, as described below, the Company includes probable expansion airspace that has yet to be permitted in the calculation of the total remaining useful life of the landfill. If it is determined that expansion capacity should no longer be considered in calculating the recoverability of a landfill asset, the Company may be required to recognize an asset impairment or incur significantly higher amortization expense. If at any time the Company makes the decision to abandon the expansion effort, the capitalized costs related to the expansion effort are expensed immediately. Landfill assets—Landfill assets include the costs of landfill site acquisition, permits and cell construction incurred to date. These amounts are recorded at cost, which includes capitalized interest as applicable. Landfill assets, net of amortization, are combined with management's estimate of the costs required to complete construction of the landfill to determine the amount to be amortized over the remaining estimated useful economic life of a site. Amortization of landfill assets is recorded on a units-of-consumption basis, such that the landfill assets should be completely amortized at the date the landfill ceases accepting waste. Amortization totaled $10.9 million, $12.3 million and $10.3 million for the years ended December 31, 2020, 2019 and 2018, respectively. Changes in the determination of when the landfill will cease accepting waste, either through a business decision by the Company, determination that expansion capacity should no longer be considered probable or changes in estimates on annual airspace consumption, will impact the amortization expense of the landfill assets. Changes in estimated costs to complete construction are applied prospectively to the amortization rate. Landfill capacity—Landfill capacity, which is the basis for the amortization of landfill assets and for the accrual of final closure and post-closure obligations, represents total permitted airspace plus unpermitted airspace that management believes is highly probable of ultimately being permitted. As of December 31, 2020, there were no unpermitted expansions included in the Company's landfill accounting model. If actual expansion airspace is significantly different from management's estimate of expansion airspace, the amortization rates used for the units-of-consumption method would change, therefore impacting our profitability. As of December 31, 2020, the Company had 9 active landfill sites (including the Company's two non-commercial landfills), which have estimated remaining lives (based on anticipated waste volumes and remaining highly probable airspace) as follows:
Facility Name |  | Location |  | Remaining Lives (Years) |  | Permitted Remaining Highly Probable Airspace (cubic yards) (in thousands)
Buttonwillow |  | California |  | 22 |  | 5,739 |
Deer Park |  | Texas |  | 2 |  | 67 |
Deer Trail |  | Colorado |  | 27 |  | 1,629 |
Grassy Mountain |  | Utah |  | 41 |  | 4,710 |
Kimball |  | Nebraska |  | 6 |  | 144 |
Lambton |  | Ontario, Canada |  | 51 |  | 4,633 |
Lone Mountain |  | Oklahoma |  | 32 |  | 3,803 |
Ryley |  | Alberta, Canada |  | 5 |  | 575 |
Sawyer |  | North Dakota |  | 68 |  | 3,416 |
|  |  |  |  |  | 24,716 |
At December 31, 2020 and 2019, the Company had no cubic yards of permitted, but not highly probable, airspace. The following table presents the remaining highly probable airspace from January 1, 2018 through December 31, 2020 (in thousands of cubic yards):
| 2020 |  | 2019 |  | 2018
Remaining capacity, beginning of year | 28,494 |  |  | 29,760 |  |  | 31,113 |
Changes in highly probable airspace, net | (2,962) |  |  | — |  |  | (223) |
Consumed | (816) |  |  | (1,266) |  |  | (1,130) |
Remaining capacity, end of year | 24,716 |  |  | 28,494 |  |  | 29,760 |
During the year ended December 31, 2020, the Company took actions to begin the closure of two of the Company's commercial landfill sites, Altair and Westmorland, and is therefore classifying these landfills as inactive as of December 31, 2020. During 2020, the Altair landfill, a non-hazardous landfill, reached permitted capacity. Airspace consumed from the Altair landfill in the years ended December 31, 2020, 2019 and 2018 was 25, 132 and 127 thousand cubic yards, respectively. During 2020, the Company decided to close the Westmorland landfill, a hazardous landfill, due to the costs of obtaining and maintaining permits and operating the landfill. No airspace had been consumed at the Westmorland landfill in the years ended December 31, 2020, 2019 and 2018. The change in the highly probable airspace, net in the table above is predominately the result of the Company's decision to close the Westmorland and Altair landfills. Amortization of cell construction costs and accrual of cell closure obligations—Landfills are typically comprised of a number of cells, which are constructed within a defined acreage (or footprint). The cells are typically discrete units, which require both separate construction and separate capping and closure procedures. Cell construction costs are the costs required to excavate and construct the landfill cell. These costs are typically amortized on a units-of-consumption basis, such that they are completely amortized when the specific cell ceases accepting waste. In some instances, the Company has landfills that are engineered and constructed as "progressive trenches." In progressive trench landfills, a number of contiguous cells form a progressive trench. In those instances, the Company amortizes cell construction costs over the airspace within the entire trench, such that the cell construction costs will be fully amortized at the end of the trench useful life. The design and construction of a landfill does not create a landfill asset retirement obligation. Rather, the asset retirement obligation for cell closure (the cost associated with capping each cell) is incurred in relatively small increments as waste is placed in the landfill. Therefore, the cost required to construct the cell cap is capitalized as an asset retirement cost and a liability of an equal amount is established, based on the discounted cash flow associated with each capping event, as airspace is consumed. Spending for cell capping is reflected as environmental expenditures within operating activities in the consolidated statements of cash flows. Landfill final closure and post-closure liabilities—The balance of landfill final closure and post-closure liabilities at December 31, 2020 and 2019 was $48.4 million and $39.4 million, respectively. The Company has material financial commitments for the costs associated with requirements of the Environmental Protection Agency ("EPA") and the comparable regulatory agency in Canada for landfill final closure and post-closure activities. The Company develops estimates for the cost of these activities based on an evaluation of site-specific facts and circumstances, including the Company's interpretation of current regulatory requirements and proposed regulatory changes. Such estimates may change in the future due to various circumstances including, but not limited to, permit modifications, changes in legislation or regulations, technological changes and results of environmental studies. Final closure costs are the costs incurred after the site ceases to accept waste, but before the landfill is certified as closed by the applicable state regulatory agency. These costs generally include the costs required to cap the final cell of the landfill (if not included in cell closure), the costs required to dismantle certain structures for landfills and other landfill improvements, and regulation-mandated groundwater monitoring and leachate management. Post-closure costs involve the maintenance and monitoring of a landfill site that has been certified closed by the applicable regulatory agency. These costs generally include groundwater monitoring and leachate management. Regulatory post-closure periods are generally 30 years after landfill closure. Final closure and post-closure obligations are accrued on a units-of-consumption basis, such that the present value of the final closure and post-closure obligations are fully accrued at the date the landfill ceases accepting waste. Cell closure, final closure and post-closure costs (also referred to as "asset retirement obligations") are calculated by estimating the total obligation in current dollars, adjusted for inflation (1.02% during both 2020 and 2019) and discounted at the Company's credit-adjusted risk-free interest rate (5.60% and 6.02% during 2020 and 2019, respectively)
Non-Landfill Closure and Post-Closure Liabilities | Non-Landfill Closure and Post-Closure Liabilities The balance of non-landfill closure and post-closure liabilities at December 31, 2020 and 2019 was $39.5 million and $36.3 million, respectively. Non-landfill closure and post-closure obligations arise when the Company commences non-landfill facility operations and include costs required to dismantle and decontaminate certain structures and other costs incurred during the closure process. Post-closure costs, if required, include associated maintenance and monitoring costs as required by the closure permit. Post-closure periods are performance-based and are not typically specified in terms of years in the closure permit, but generally range from 10 to 30 years or more. The Company records its non-landfill closure and post-closure liability by: (i) estimating the current cost of closing a non-landfill facility and the post-closure care of that facility, if required, based upon the closure plan that the Company is required to follow under its operating permit, or in the event the facility operates with a permit that does not contain a closure plan, based upon legally enforceable closure commitments made by the Company to various government agencies; (ii) estimates as to when future operations may cease; (iii) cost estimates of closing the non-landfill facility using the inflation rate to the time of closing; and (iv) discounting the future value back to the present using the credit-adjusted risk-free interest rate. The estimates for non-landfill closure and post-closure liabilities are inherently uncertain due to the possibility that permit and regulatory requirements will change in the future, impacting the estimation of total costs and the timing of the expenditures. Management reviews non-landfill closure and post-closure liabilities for changes to key assumptions that would impact the amount of the recorded liabilities. Changes that would prompt management to revise a liability estimate include changes in legal requirements that impact the Company's expected closure plan or scope of work, in the market price of a significant cost item, in the estimate as to when future operations at a location might cease or in the expected timing of the costs. Changes in estimates for non-landfill closure and post-closure events immediately impact the liability and the value of the corresponding asset. If a change is made to a fully-amortized asset, the adjustment is charged immediately to expense. When a change in estimate relates to an asset that has not been fully amortized, the adjustment to the asset is recognized in income prospectively as a component of amortization. Historically, changes to non-landfill closure and post-closure estimates have not been material.
Remedial Liabilities | Remedial Liabilities The balance of remedial liabilities at December 31, 2020 and 2019 was $114.8 million and $114.2 million, respectively. Remedial liabilities, including Superfund liabilities, include the costs of removal or containment of contaminated material, treatment of potentially contaminated groundwater and maintenance and monitoring costs necessary to comply with regulatory requirements. Most of the Company's remedial liabilities relate to the active and inactive hazardous waste treatment and disposal facilities which the Company acquired in the last 18 years and Superfund sites owned by third parties for which the Company, or the prior owners of certain of the Company's facilities for which the Company may have certain indemnification obligations, have been identified as potentially responsible parties ("PRPs") or potential PRPs. The Company's estimate of remedial liabilities involves an analysis of such factors as: (i) the nature and extent of environmental contamination (if any); (ii) the terms of applicable permits and agreements with regulatory authorities as to cleanup procedures and whether modifications to such permits and agreements will likely need to be negotiated; (iii) the cost of performing anticipated cleanup activities based upon current technology; and (iv) in the case of Superfund and other sites where other parties will also be responsible for a portion of the cleanup costs, the likely allocation of such costs and the ability of such other parties to pay their share. The measurement of remedial liabilities is reviewed at least quarterly and changes in estimates are recognized in the consolidated statements of operations when identified. The Company periodically evaluates potential remedial liabilities at sites that it owns or operates or to which the Company or the sellers of the Chemical Services Division of Safety-Kleen ("CSD") assets (or the respective predecessors of the Company or such sellers) transported or disposed of waste, including 130 Superfund sites as of December 31, 2020. The Company periodically reviews and evaluates sites requiring remediation giving consideration to the nature (i.e., owner, operator, arranger, transporter or generator) and the extent (i.e., amount and nature of waste hauled to the location, number of years of site operations or other relevant factors) of the Company's (or such sellers') alleged connection with the site, the extent (if any) to which the Company believes it may have an obligation to indemnify cleanup costs in connection with the site, the regulatory context surrounding the site, the accuracy and strength of evidence connecting the Company (or such sellers) to the location, the number, connection and financial ability of other named and unnamed PRPs and the nature and estimated cost of the likely remedy. Where the Company concludes that it is probable that a liability has been incurred and an amount can be estimated, a liability is recognized. Remedial liabilities are inherently difficult to estimate. Estimating remedial liabilities requires that the existing environmental contamination be understood. There are risks that the actual quantities of contaminants differ from the results of the site investigation, and that contaminants exist that have not been previously identified. In addition, the amount of remedial liabilities recorded is dependent on the remedial method selected. There is a risk that funds will be expended on a remedial solution that is not successful, which could result in the Company incurring the incremental costs of an alternative solution. Such estimates, which are subject to change, are subsequently revised if and when additional or new information becomes available. Remedial liabilities are discounted when the timing of the payments is determinable and the amounts are estimable. In the case of remedial liabilities assumed in connection with acquisitions, acquired liabilities are recorded at fair value as of the dates of the acquisitions calculated by inflating costs in current dollars using an estimate of future inflation rates as of the respective acquisition dates until the expected time of payment, and then discounting the amount of the payments to their present value using a risk-free discount rate as of the acquisition dates. Discount rates used in the present value determination of the Company's remedial liabilities range from 1.37% to 4.90%.
Self Insurance Liabilities | Self-Insurance Liabilities The Company self-insures a significant portion of expected losses related to workers' compensation, employee medical, comprehensive general liability and vehicle liability. Liabilities associated with these losses are recorded based on the Company's estimates of the ultimate cost to settle incurred claims. These recorded liabilities are estimated based on independent actuarial estimates and judgments which consider the frequency and settlement amount of historical claims data.
Revenue recognition | Revenue Recognition The Company generates service and product revenues through the following operating segments: Environmental Services and Safety-Kleen. The Company recognizes revenue when control of the promised goods or services is transferred to the Company's customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The majority of the Company’s revenues are for services, which are recognized based on time and materials incurred at contractually agreed-upon rates. Product revenues are recognized when the products are delivered and control transfers to the customer. The Company’s payment terms vary by the type and location of its customers and the products or services offered. The periods between invoicing and when payments are due are not significant. Amounts billed to customers related to shipping and handling are classified as revenue, and the Company's shipping and handling costs are included in costs of revenues. In the course of operations, the Company collects sales tax and other excise taxes from its customers and recognizes a current liability, which is then relieved when the taxes are remitted to the appropriate government authorities. The Company excludes sales and other excise taxes that it collects from customers from its revenues. The Company's Environmental Services operating segment generally has the following three sources of revenue: Technical Services—Technical Services revenues are generated from fees charged for waste material management and disposal services including onsite environmental management services, collection and transportation, packaging, recycling, treatment and disposal of waste. Revenue is primarily generated by short-term projects, most of which are governed by master service agreements that are long-term in nature. These master service agreements are typically entered into with the Company's larger customers and outline the pricing and legal frameworks for such arrangements. Services are provided based on purchase orders or agreements with the customer and include prices based upon units of volume of waste, and transportation and other fees. Collection and transportation revenues are recognized over time, as the customer receives and consumes the benefits of the services as they are being performed and the Company has a right to payment for performance completed to date. The Company uses the input method to recognize revenue over time, using time and materials incurred as a basis for measuring the satisfaction of the performance obligation. Revenues for treatment and disposal of waste are recognized upon completion of treatment, final disposition in a landfill or incineration, or when the waste is shipped to a third-party for processing and disposal. The Company periodically enters into bundled arrangements for the collection and transportation and disposal of waste. For such arrangements, transportation and disposal are considered distinct performance obligations and the Company allocates revenue to each based on the relative standalone selling price (i.e. the estimated price that a customer would pay for the services on a standalone basis). Revenues and the related costs from waste that is not yet completely processed and disposed of are deferred. The deferred revenues and costs are recognized when the disposal services are completed. The period between collection and transportation and the final processing and disposal ranges depending on location of the customer, but generally is measured in days. Field and Emergency Response Services—Field Services revenues are generated from cleanup services at customer sites or other locations. Services include confined space entry for tank cleaning, site decontamination, large remediation projects, demolition, spill cleanup on land and water, railcar cleaning, product recovery and transfer and vacuum services. Additional services include filtration and water treatment services. Response services for environmental emergencies include any scale from man-made disasters such as oil spills, to natural disasters such as hurricanes. More recently, demand has increased for projects involving contagion disinfection, decontamination and disposal services in response to the COVID-19 pandemic. Field and emergency response services are provided based on purchase orders or agreements with customers and include prices generally based upon daily, hourly or job rates for equipment, materials and personnel. The Company recognizes revenue for these services over time, as the customer receives and consumes the benefits of the service as they are being performed and the Company has a right to payment for performance completed to date. The Company uses the input method to recognize revenue over time, based on time and materials incurred. The duration of such services can be over a number of hours, several days or even months for larger scale projects. Industrial Services and Other—Industrial Services revenues are generated from industrial and specialty services provided to refineries, mines, upgraders, chemical plants, pulp and paper mills, manufacturing facilities, power generation facilities and other industrial customers throughout North America. Services include in-plant cleaning and maintenance services, plant outage and turnaround services, decoking and pigging, chemical cleaning, high and ultra-high pressure water cleaning, pipeline inspection and coating services, large tank and surface impoundment cleaning, oilfield transport, daylighting, production services and upstream energy services, such as exploration and drilling for industrial oil and gas customers. Services are provided based on purchase orders or agreements with the customer and include prices based upon daily, hourly or job rates for equipment, materials and personnel. The Company recognizes revenue for these services over time, as the customer receives and consumes the benefits of the services as they are being performed and the Company has a right to payment for performance completed to date. The Company uses the input method to recognize revenue over time, based on time and materials incurred. The Company's Safety-Kleen operating segment generally has the following two sources of revenue: Safety-Kleen Environmental Services—Safety-Kleen Environmental Services revenues are generated from providing parts washer services, containerized waste handling and disposal services, oil collection services, vacuum services, direct sales of blended oil products and other complementary services and product sales. Containerized waste services consist of profiling, collecting, transporting and recycling or disposing of a wide variety of waste. Other products and services include sale of complementary supply products including automotive fluids and shop supplies and other environmental services. Parts washer services include customer use of our parts washer equipment, cleaning and maintenance of the parts washer equipment and removal and replacement of used cleaning fluids. Parts washer services are considered a single performance obligation due to the highly integrated and interdependent nature of the arrangement. Revenue from parts washer services is recognized over the service interval as the customer receives the benefit of the services. Collection and transportation revenues are recognized over time, as the customer receives and consumes the benefits of the services as they are being performed and the Company has a right to payment for performance completed to date. The Company uses the input method to recognize revenue over time, based on time and materials incurred. Product revenue is recognized upon the transfer of control whereby control transfers when the products are delivered to the customer. Safety-Kleen Oil—Revenues from Safety-Kleen Oil are generated from sales of high-quality base and blended lubricating oils to third-party distributors, government agencies, fleets, railroads and industrial customers. The business also sells recycled fuel oil to asphalt plants, industrial plants and pulp and paper companies. The used oil is also processed into vacuum gas oil which can be further re-refined into lubricant base oils or sold directly into the marine diesel oil fuel market. Revenue for oil products is recognized at a point in time, upon the transfer of control. Control transfers when the products are delivered to the customer.
Foreign Currency | Foreign Currency The Company has international operations, substantially all of which are located in Canada from an operational perspective with more limited administrative support services located in India. The functional currencies of foreign operations are the local currency and therefore assets and liabilities of those foreign operations are translated to U.S. Dollars at the exchange rate in effect at the balance sheet date and revenue and expenses at the average exchange rate for the period. Gains and losses from the translation of the consolidated financial statements of foreign subsidiaries into U.S. Dollars are included in stockholders' equity as a component of accumulated other comprehensive loss. Gains and losses from transactions not denominated in the functional currency of an entity are recognized in the consolidated statements of operations. Recorded balances that are denominated in a currency other than the functional currency are remeasured to the functional currency using the exchange rate at the balance sheet date and gains or losses are recorded in the consolidated statements of operations.
Advertising Expense | Advertising Expense Advertising costs are expensed as incurred. Advertising expense was $9.0 million in 2020, $9.8 million in 2019 and $10.5 million in 2018.
Stock-Based Compensation | Stock-Based Compensation Stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which generally represents the vesting period. In addition, the Company issues awards with performance targets established at the grant date. The expense for these awards is recognized over the requisite service period when management believes it is probable those performance targets will be achieved. The fair value of the Company's grants are based on the closing price of the Company's common stock on the respective dates of grant. Forfeitures are recognized as they occur. Stock-based compensation is recognized in selling, general and administrative expense.
Income Taxes | Income Taxes Current income tax expense approximates cash to be paid or refunded for taxes for the applicable period. Deferred tax expense or benefit is the result of changes between deferred tax assets and liabilities. Deferred tax assets and liabilities are determined based upon the temporary differences between the financial statement basis and tax basis of assets and liabilities as well as from net operating loss and tax credit carryforwards as measured by the enacted tax rates which will be in effect when these differences reverse. The effect of a change in tax rates on deferred tax assets and liabilities is generally recognized in income in the period that includes the enactment date. The Company evaluates the recoverability of future tax deductions and credits and a valuation allowance is established by tax jurisdiction when, based on an evaluation of both positive and negative objective verifiable evidence, it is more likely than not that some portion or all of deferred tax assets will not be realized. The Company recognizes and measures a tax benefit from uncertain tax positions when it is more likely than not that the tax position will be sustained upon examination by the taxing authorities, based on the technical merits of the position. The Company recognizes a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. The Company adjusts these liabilities when its judgment changes as a result of the evaluation of new information not previously available. Due to the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from the current estimate or future recognition of an unrecognized benefit. These differences will be reflected as increases or decreases to income tax expense in the period in which they are determined. Liabilities for unrecognized tax benefits are included within other long-term liabilities in the consolidated balance sheets. The Company recognizes interest and penalties related to unrecognized tax benefits within the provision for income taxes line in the consolidated statements of operations. Accrued interest and penalties are included within the other long-term liabilities line in the consolidated balance sheet.
Earnings per Share ("EPS") | Earnings per Share ("EPS") Basic EPS is calculated by dividing net income by the weighted average number of common shares outstanding during the period. Diluted EPS gives effect to all potentially dilutive common shares that were outstanding during the period.
Leases | Leases The Company’s leases predominately relate to real estate, equipment, such as vehicles and industrial equipment utilized in operations, and rail cars utilized in connection with the Company’s transportation needs. Contracts are reviewed at inception to determine if the arrangement is a lease and, if so, whether it is an operating or finance lease. For all of its leases, the Company has elected not to separate lease and nonlease components, such as common area maintenance. The Company generally enters into long-term real estate leases with three to ten-year terms and long-term non-real estate leases with two to eight-year terms. In the normal course of business, the Company also enters into short-term leases having terms of less than one-year. These leases are generally equipment leases entered into for short periods of time (e.g. daily, weekly or monthly) to satisfy immediate and/or short-term operational needs of the business which can arise based upon the nature of particular services performed or seasonality factors. The Company has elected not to recognize right of use ("ROU") assets and lease liabilities for these short-term leases. Expense for all such short-term leases is disclosed as short-term lease cost as shown in Note 18, "Leases." Operating and finance leases with terms exceeding one year are recognized as ROU assets and lease liabilities and measured based on the present value of the future lease payments over the lease term at commencement date. When applicable, the ROU asset includes any lease payments made at or before the commencement date and initial direct costs incurred and is reduced by lease incentives received under the lease agreement. Certain of the Company's real estate leases contain escalating future lease payments. Escalating lease payments that are based upon explicit amounts contained in the lease or an index (e.g., consumer price index) are included in its determination of future lease payments to determine the ROU asset and lease liability recognized at the commencement date. Any differences in the future lease payments from initial recognition are not anticipated to be material and will be recorded as variable lease cost in the period incurred. The variable lease cost will also include the Company’s portion of property tax, utilities and common area maintenance. A significant portion of the Company’s real estate lease agreements include renewal periods at the Company’s option. The Company includes these renewal periods in the lease term only when renewal is reasonably certain based upon facts and circumstances specific to the lease and known by the Company. Certain of the equipment and rail car leases transfer ownership upon the conclusion of the lease term and as such, are classified as finance leases. Leases containing purchase options are classified as finance leases only when it is reasonably certain that the Company will execute such options. The Company uses its incremental borrowing rate on collateralized debt based on the information available at the lease commencement date in determining the present value of future lease payments as the implicit rate is typically not readily determinable. For operating leases, lease cost is recognized on a straight-line basis over the lease term and is included in cost of revenues or selling, general and administrative expenses depending on the use of the asset. For finance leases, ROU assets are amortized on a straight-line basis over the shorter of the lease term or the estimated useful life of the leased asset and interest expense is recognized based on the incremental borrowing rate. Amortization and interest expense for finance leases are included in depreciation and amortization and interest expense, net of interest income, respectively. The Company adopted Accounting Standards Codification 842, Leases ("ASC 842"), on January 1, 2019 using the modified retrospective method of adoption. Prior period amounts have not been adjusted and continue to be reported in accordance with the Company's historical accounting methodology pursuant to Accounting Standards Codification 840, Leases. The standard did not have a material impact on the consolidated statements of operations or cash flows.

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