Quarterly report pursuant to Section 13 or 15(d)


9 Months Ended
Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Principles of Consolidation
In our opinion, the accompanying interim, unaudited, consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. These consolidated financial statements contain all adjustments (consisting of normal recurring accruals) necessary to present fairly our financial position as of September 30, 2018, our results of operations for the three and nine months ended September 30, 2018 and 2017, and cash flows for the nine months ended September 30, 2018 and 2017. The results reported in these consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for any other period or the entire year. The interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2017.
For interim consolidated financial statement purposes, we provide for accruals under our various employee benefit plans for each three month period based on one quarter of the estimated annual expense.
Certain prior year amounts have been reclassified to conform to the current year presentation. These reclassifications had no material impact on our financial position or results of operations.
Fair Value of Financial Instruments
The carrying amounts of our cash and cash equivalents, accounts receivable, finance receivables and accounts payable approximate fair value as of September 30, 2018. The fair values of our investment securities are disclosed in note 5, our recognized multiemployer pension withdrawal liabilities in note 7, our short and long-term debt in note 9 and our derivative instruments in note 14. We utilized Level 1 inputs in the fair value hierarchy of valuation techniques to determine the fair value of our cash and cash equivalents, and Level 2 inputs to determine the fair value of our accounts receivable, finance receivables and accounts payable.
Property, Plant and Equipment
Property, plant and equipment are carried at cost. We evaluate the useful lives of our property, plant and equipment based on our usage, maintenance and replacement policies, and taking into account physical and economic factors that may affect the useful lives of the assets. As part of our ongoing investment in transformation, beginning in the third quarter of 2018, we revised our estimates of useful lives for building improvements and vehicles based on our current assessment of these factors. In general, the change in estimate had the effect of lengthening the useful lives of vehicles and building improvements. Depreciation and amortization are provided by the straight-line method over the estimated useful lives of the assets, which are as follows: Vehicles-6 to 15 years; Aircraft-12 to 30 years; Buildings-20 to 40 years; Leasehold Improvements-lesser of asset useful life or lease term; Plant Equipment-3 to 20 years; Technology Equipment-3 to 5 years. The costs of major airframe and engine overhauls, as well as routine maintenance and repairs, are charged to expense as incurred.
This change in estimate was applied prospectively effective for the third quarter of 2018. See"Consolidated Operating Expenses" of Item 2 "Management’s Discussion and Analysis of Financial Condition and Results of Operations" for the discussion of the impact to "Depreciation and amortization."
Accounting Estimates
The preparation of the accompanying interim, unaudited, consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingencies at the date of the consolidated financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Estimates have been prepared on the basis of the most current and best information and actual results could differ materially from those estimates.