Contingent Liabilities	3 Months Ended
Contingent Liabilities	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingent Liabilities	Contingent Liabilities Product Liability Claims The Company is a defendant in various product liability claims brought in numerous jurisdictions in which individuals seek damages resulting from motor vehicle accidents allegedly caused by defective tires manufactured by the Company. Each of the product liability claims faced by the Company generally involves different types of tires and circumstances surrounding the accident such as different applications, vehicles, speeds, road conditions, weather conditions, driver error, tire repair and maintenance practices, service life conditions, as well as different jurisdictions and different injuries. In addition, in many of the Company’s product liability lawsuits the plaintiff alleges that his or her harm was caused by one or more co-defendants who acted independently of the Company. Accordingly, both the claims asserted and the resolutions of those claims have an enormous amount of variability. The aggregate amount of damages asserted at any point in time is not determinable since often times when claims are filed, the plaintiffs do not specify the amount of damages. Even when there is an amount alleged, at times the amount is wildly inflated and has no rational basis. The fact that the Company is a defendant in product liability lawsuits is not surprising given the current litigation climate, which is largely confined to the United States. However, the fact that the Company is subject to claims does not indicate that there is a quality issue with the Company’s tires. The Company sells approximately 30 to 35 million passenger car, light truck, SUV, TBR and motorcycle tires per year in North America. The Company estimates that approximately 300 million Company-produced tires made up of thousands of different specifications are still on the road in North America. While tire disablements do occur, it is the Company’s and the tire industry’s experience that the vast majority of tire failures relate to service-related conditions, which are entirely out of the Company’s control, such as failure to maintain proper tire pressure, improper maintenance, improper repairs, road hazard and excessive speed. The Company accrues costs for product liability at the time a loss is probable and the amount of loss can be estimated. The Company believes the probability of loss can be established and the amount of loss can be estimated only after certain minimum information is available, including verification that Company-produced product were involved in the incident giving rise to the claim, the condition of the product purported to be involved in the claim, the nature of the incident giving rise to the claim and the extent of the purported injury or damages. In cases where such information is known, each product liability claim is evaluated based on its specific facts and circumstances. A judgment is then made to determine the requirement for establishment or revision of an accrual for any potential liability. Adjustments to estimated reserves are recorded in the period in which the change in estimate occurs. The liability often cannot be determined with precision until the claim is resolved. Pursuant to ASU 450 "Contingencies," the Company accrues the minimum liability for each known claim when the estimated outcome is a range of probable loss and no one amount within that range is more likely than another. The Company uses a range of losses because an average cost would not be meaningful since the product liability claims faced by the Company are unique and widely variable, and accordingly, the resolutions of those claims have an enormous amount of variability. The costs have ranged from zero dollars to $33 million in one case with no “average” that is meaningful. No specific accrual is made for individual unasserted claims or for premature claims, asserted claims where the minimum information needed to evaluate the probability of a liability is not yet known. However, an accrual for such claims based, in part, on management’s expectations for future litigation activity and the settled claims history is maintained. The Company periodically reviews such estimates and any adjustments for changes in reserves are recorded in the period in which the change in estimate occurs. Because of the speculative nature of litigation in the U.S., the Company does not believe a meaningful aggregate range of potential loss for asserted and unasserted claims can be determined. While the Company believes its reserves are reasonably stated, it is possible an individual claim from time to time may result in an aberration from the norm and could have a material impact. The time frame for the payment of a product liability claim is too variable to be meaningful. From the time a claim is filed to its ultimate disposition depends on the unique nature of the case, how it is resolved - claim dismissed, negotiated settlement, trial verdict or appeals process - and is highly dependent on jurisdiction, specific facts, the plaintiff’s attorney, the court’s docket and other factors. Given that some claims may be resolved in weeks and others may take five years or more, it is impossible to predict with any reasonable reliability the time frame over which the accrued amounts may be paid. The Company regularly reviews the probable outcome of outstanding legal proceedings and the availability and limits of the insurance coverage, and accrues for such legal proceedings at the time a loss is probable and the amount of the loss can be estimated. As part of its regular review, the Company monitors trends that may affect its ultimate liability and analyzes the developments and variables likely to affect pending and anticipated claims against the Company and the reserves for such claims. The Company utilizes claims experience, as well as trends and developments in the litigation climate, in estimating its required accrual. Based on the Company's first quarter review, coupled with normal activity, including the addition of another quarter of self-insured incidents, settlements and changes in the amount of reserves, the Company increased its accrual to $114,543 at March 31, 2019 from $112,124 at December 31, 2018. The addition of another quarter of self-insured incidents accounted for an increase of $9,286 in the Company's product liability reserve in the first quarter of 2019. Settlements, changes in the amount of reserves for cases where sufficient information is known to estimate a liability, and changes in assumptions decreased the liability by $1,492. The Company paid $5,375 during the first quarter of 2019 to resolve cases and claims. The Company’s product liability reserve balance at March 31, 2019 totaled $114,543 (the current portion of $30,718 is included in Accrued liabilities and the long-term portion is included in Other long-term liabilities on the Condensed Consolidated Balance Sheets), and the balance at December 31, 2018 totaled $112,124 (current portion of $30,550). The product liability expense reported by the Company includes amortization of insurance premium costs, adjustments to settlement reserves and legal costs incurred in defending claims against the Company. Legal costs are expensed as incurred and product liability insurance premiums are amortized over coverage periods. For the three months ended March 31, 2019 and 2018, product liability expense totaled $10,817 and $15,068, respectively. Product liability expenses are included in Cost of products sold in the Condensed Consolidated Statements of Income.