Impairment of Long-Lived Assets
Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. For the purpose of reviewing restaurant assets to be held and used for potential impairment, assets are grouped together at the market level, or in the case of a potential relocation or closure, at the restaurant level. We manage our restaurants as a group with significant common costs and promotional activities; as such, an individual restaurant’s cash flows are not generally independent of the cash flows of others in a market. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized as the amount by which the carrying amount of the asset exceeds the fair value of the asset.
During the years ended December 31, 2017, 2016 and 2015, an aggregate impairment charge of $3,291, $17,394 and $6,675, respectively, was recognized in loss on disposal and impairment of assets in the consolidated statement of income. During the year ended December 31, 2017, the impairment charges resulted primarily from the closure of a small number of underperforming Chipotle restaurants. Impairment charges recognized during the year ended December 31, 2016 resulted primarily from the impairment of ShopHouse Southeast Asian Kitchen restaurants which were closed during 2017. During the year ended December 31, 2015, the impairment charges resulted from an internally developed software program we chose not to implement and the related hardware, the discontinued use of certain kitchen equipment from our restaurants, as well as restaurant relocations. The fair value of restaurants was determined using Level 3 inputs (unobservable inputs) based on a discounted cash flows method. See “Fair Value Measurements” below for a description of level inputs.
Deferred tax assets and liabilities are recognized at enacted income tax rates for the temporary differences between the financial reporting bases and the tax bases of our assets and liabilities. Any effects of changes in income tax rates or tax laws are included in the provision for income taxes in the period of enactment. The deferred income tax impacts of investment tax credits are recognized as an immediate adjustment to income tax expense. When it is more likely than not that a portion or all of a deferred tax asset will not be realized in the future, we provide a corresponding valuation allowance against the deferred tax asset, except for deferred tax assets related to stock awards when there is sufficient future taxable income to recover the deferred tax assets. When it is more likely than not that a position will be sustained upon examination by a tax authority that has full knowledge of all relevant information, we measure the amount of tax benefit from our position and record the largest amount of tax benefit that is greater than 50% likely of being realized after settlement with a tax authority. Our policy is to recognize interest to be paid on an underpayment of income taxes in interest expense and any related statutory penalties in the provision for income taxes in the consolidated statement of income.
Restaurant Pre-Opening Costs
Pre-opening costs, including rent, wages, benefits and travel for training and opening teams, food and other restaurant operating costs, are expensed as incurred prior to a restaurant opening for business, and are included in operating expenses on the consolidated statement of income.
We are self-insured for a significant portion of our risks and associated liabilities with respect to workers’ compensation, employee health, general liability, automobile, and property damage. Pursuant to these policies, we are responsible for losses up to varying deductibles and are required to estimate a liability that represents the ultimate exposure for aggregate losses below those limits. This liability is based on our estimates of the ultimate costs to be incurred to settle known claims and, where applicable, claims not reported as of the balance sheet date. The estimated liability is not discounted and is based on a number of assumptions and factors, including historical trends, actuarial assumptions, and economic conditions. If actual trends differ from the estimates, the financial results could be impacted. As of December 31, 2017 and 2016, $37,096 and $35,550, respectively, of the estimated liability was included in accrued payroll and benefits and $14,014 and $13,881, respectively, was included in accrued liabilities in the consolidated balance sheet.