Legal Proceedings and Other Contingencies	12 Months Ended
Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Legal Proceedings and Other Contingencies	OTE 22. Legal Proceedings and Other Contingencies Various legal actions, claims, assessments and other contingencies arising in the ordinary course of business are pending against GATX and certain of our subsidiaries. These matters are subject to many uncertainties, and it is possible that some of these matters could ultimately be decided, resolved or settled adversely. Viareggio Derailment In June 2009, a train consisting of fourteen liquefied petroleum gas (“LPG”) tank cars owned by GATX Rail Austria GmbH and its subsidiaries (collectively, “GRA”) derailed while passing through the City of Viareggio, in the province of Lucca, Italy. Five tank cars overturned and one of the overturned cars was punctured by a peg or obstacle along the side of the track, resulting in a release of LPG, which subsequently ignited. The accident resulted in multiple deaths, personal injuries and property damage. The LPG tank cars were leased to FS Logistica S.p.A., a subsidiary of the Italian state-owned railway, Ferrovie dello Stato S.p.A (the “Italian Railway”). In January 2017, the court of Lucca found various Italian Railway companies, GRA, and certain of their employees guilty of negligence-based crimes related to the accident. The court imposed a fine of 1.4 million Euros against GRA and prison sentences against the employees. GRA has appealed and, pending the final disposition of the appeal, these fines and penalties are not enforceable. GRA believes that it and its employees acted diligently and in accordance with all applicable laws and regulations at all times. Appellate hearings began on November 13, 2018, but the duration of the first level of appeal is currently unknown. With respect to civil claims, the insurers for the Italian Railway and GRA have fully settled and resolved most of the claims arising out of the accident. GRA will continue to incur legal expenses for the criminal appeals although they are not expected to be material. We cannot predict the outcome of the appellate process and thus cannot reasonably estimate the possible amount or range of costs that may be ultimately incurred in connection with this litigation. Other Litigation GATX and its subsidiaries have been named as defendants in various other legal actions and claims, governmental proceedings, and private civil suits arising in the ordinary course of business, including environmental matters, workers’ compensation claims, and other personal injury claims. Some of these proceedings include claims for punitive as well as compensatory damages. Several of our subsidiaries have also been named as defendants or co-defendants in cases alleging injury caused by exposure to asbestos. The plaintiffs seek an unspecified amount of damages based on common law, statutory, or premises liability or, in the case of claims against ASC, the Jones Act, which provides limited remedies to certain maritime employees. In addition, demand has been made against GATX for asbestos-related claims under limited indemnities given in connection with the sale of certain of our former subsidiaries. Litigation Accruals We have recorded accruals totaling $5.8 million at December 31, 2018 for losses related to those litigation matters that we believe to be probable and for which an amount of loss can be reasonably estimated. However, we cannot determine a reasonable estimate of the maximum possible loss or range of loss for these matters given that they are at various stages of the litigation process and each case is subject to the inherent uncertainties of litigation (such as the strength of our legal defenses and the availability of insurance recovery). Although the maximum amount of liability that may ultimately result from any of these matters cannot be predicted with absolute certainty, management expects that none of the matters for which we have recorded an accrual, when ultimately resolved, will have a material adverse effect on our consolidated financial position or liquidity. It is possible, however, that the ultimate resolution of one or more of these matters could have a material adverse effect on our results of operations in a particular quarter or year if such resolution results in liability that materially exceeds the accrued amount. In addition, we have other litigation matters pending for which we have not recorded any accruals because our potential liability for those matters is not probable or cannot be reasonably estimated based on currently available information. For those matters where we have not recorded an accrual but a loss is reasonably possible, we cannot determine a reasonable estimate of the maximum possible loss or range of loss for these matters given that they are at various stages of the litigation process and each case is subject to the inherent uncertainties of litigation (such as the strength of our legal defenses and the availability of insurance recovery). Although the maximum amount of liability that may ultimately result from any of these matters cannot be predicted with absolute certainty, management expects that none of the matters for which we have not recorded an accrual, when ultimately resolved, will have a material adverse effect on our consolidated financial position or liquidity. It is possible, however, that the ultimate resolution of one or more of these matters could have a material adverse effect on our results of operations in a particular quarter or year if such resolution results in a significant liability for GATX. Environmental Our operations are subject to extensive federal, state, and local environmental regulations. Our operating procedures include practices to protect the environment from the risks inherent in full service railcar leasing, which involves maintaining railcars used by customers to transport chemicals and other hazardous materials. Under some environmental laws in the U.S. and certain other countries, the owner of a leased railcar may be liable for environmental damage and cleanup or other costs in the event of a spill or discharge of material from a railcar without regard to the owner's fault. While our standard master railcar lease agreement requires the lessee to indemnify us against environmental claims and to carry liability insurance coverage, such indemnities and insurance may not fully protect us against claims for environmental damage. Additionally, some of our real estate holdings, including previously owned properties, are or have been used for industrial or transportation-related purposes or leased to commercial or industrial companies whose activities might have resulted in discharges on the property. As a result, we are subject to environmental cleanup and enforcement actions. In particular, the federal Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”), also known as the Superfund law, as well as similar state laws, impose joint and several liability for cleanup and enforcement costs on current and former owners and operators of a site without regard to fault or the legality of the original conduct. If there are other potentially responsible parties (“PRPs”), we generally contribute to the cleanup of these sites through cost-sharing agreements with terms that vary from site to site. Costs are typically allocated based on the relative volumetric contribution of material, the period of time the site was owned or operated, and/or the portion of the site owned or operated by each PRP. At the time a potential environmental issue is identified, initial accruals for environmental liability are established when such liability is determined to be probable and a reasonable estimate of the associated costs can be made. Costs are estimated based on the type and level of investigation and/or remediation activities that our internal environmental staff (and where appropriate, independent consultants) have advised to be necessary to comply with applicable laws and regulations. Activities include surveys and environmental studies of potentially contaminated sites as well as costs for remediation and restoration of sites determined to be contaminated. In addition, we have provided indemnities for potential environmental liabilities to buyers of divested companies. In these instances, accruals are based on the scope and duration of the respective indemnities together with the extent of known contamination. Estimates are periodically reviewed and adjusted as required to reflect additional information about facility or site characteristics or changes in regulatory requirements. We conduct a quarterly environmental contingency analysis, which considers a combination of factors including independent consulting reports, site visits, legal reviews, analysis of the likelihood of participation in and the ability of other PRPs to pay for cleanup, and historical trend analyses. We are involved in administrative and judicial proceedings and other voluntary and mandatory cleanup efforts at 13 sites, including Superfund sites, for which we are contributing to the cost of performing the study or cleanup, or both, of alleged environmental contamination. As of December 31, 2018, we have recorded accruals of $13.7 million for remediation and restoration costs that we believe to be probable and for which the amount of loss can be reasonably estimated. These amounts are included in other liabilities on our balance sheet. Our environmental liabilities are not discounted. We did not materially change our methodology for identifying and calculating environmental liabilities in the last three years. Currently, no known trends, demands, commitments, events or uncertainties exist that are reasonably likely to occur and materially affect the methodology or assumptions described above. The recorded accruals represent our best estimate of all costs for remediation and restoration of affected sites, without reduction for anticipated recoveries from third parties, and include both asserted and unasserted claims. However, we are unable to provide a reasonable estimate of the maximum potential loss associated with these sites because cleanup costs cannot be predicted with certainty. Various factors beyond our control can impact the amount of loss GATX will ultimately incur with respect to these sites, including the extent of corrective actions that may be required; evolving environmental laws and regulations; advances in environmental technology, the extent of other parties' participation in cleanup efforts; developments in periodic environmental analyses related to sites determined to be contaminated, and developments in environmental surveys and studies of potentially contaminated sites. As a result, future charges associated with these sites could have a significant effect on results of operations in a particular quarter or year if the costs materially exceed the accrued amount as individual site studies and remediation and restoration efforts proceed. However, management believes it is unlikely that the ultimate cost to GATX for any of these sites, either individually or in the aggregate, will have a material adverse effect on our consolidated financial position or liquidity.

OTE 22. Legal Proceedings and Other Contingencies

Various legal actions, claims, assessments and other contingencies arising in the ordinary course of business are pending against GATX and certain of our subsidiaries. These matters are subject to many uncertainties, and it is possible that some of these matters could ultimately be decided, resolved or settled adversely.

Viareggio Derailment

In June 2009, a train consisting of fourteen liquefied petroleum gas (“LPG”) tank cars owned by GATX Rail Austria GmbH and its subsidiaries (collectively, “GRA”) derailed while passing through the City of Viareggio, in the province of Lucca, Italy. Five tank cars overturned and one of the overturned cars was punctured by a peg or obstacle along the side of the track, resulting in a release of LPG, which subsequently ignited. The accident resulted in multiple deaths, personal injuries and property damage. The LPG tank cars were leased to FS Logistica S.p.A., a subsidiary of the Italian state-owned railway, Ferrovie dello Stato S.p.A (the “Italian Railway”).

In January 2017, the court of Lucca found various Italian Railway companies, GRA, and certain of their employees guilty of negligence-based crimes related to the accident. The court imposed a fine of 1.4 million Euros against GRA and prison sentences against the employees. GRA has appealed and, pending the final disposition of the appeal, these fines and penalties are not enforceable. GRA believes that it and its employees acted diligently and in accordance with all applicable laws and regulations at all times. Appellate hearings began on November 13, 2018, but the duration of the first level of appeal is currently unknown. With respect to civil claims, the insurers for the Italian Railway and GRA have fully settled and resolved most of the claims arising out of the accident. GRA will continue to incur legal expenses for the criminal appeals although they are not expected to be material. We cannot predict the outcome of the appellate process and thus cannot reasonably estimate the possible amount or range of costs that may be ultimately incurred in connection with this litigation.

Other Litigation

GATX and its subsidiaries have been named as defendants in various other legal actions and claims, governmental proceedings, and private civil suits arising in the ordinary course of business, including environmental matters, workers’ compensation claims, and other personal injury claims. Some of these proceedings include claims for punitive as well as compensatory damages. Several of our subsidiaries have also been named as defendants or co-defendants in cases alleging injury caused by exposure to asbestos. The plaintiffs seek an unspecified amount of damages based on common law, statutory, or premises liability or, in the case of claims against ASC, the Jones Act, which provides limited remedies to certain maritime employees. In addition, demand has been made against GATX for asbestos-related claims under limited indemnities given in connection with the sale of certain of our former subsidiaries.

Litigation Accruals

We have recorded accruals totaling $5.8 million at December 31, 2018 for losses related to those litigation matters that we believe to be probable and for which an amount of loss can be reasonably estimated. However, we cannot determine a reasonable estimate of the maximum possible loss or range of loss for these matters given that they are at various stages of the litigation process and each case is subject to the inherent uncertainties of litigation (such as the strength of our legal defenses and the availability of insurance recovery). Although the maximum amount of liability that may ultimately result from any of these matters cannot be predicted with absolute certainty, management expects that none of the matters for which we have recorded an accrual, when ultimately resolved, will have a material adverse effect on our consolidated financial position or liquidity. It is possible, however, that the ultimate resolution of one or more of these matters could have a material adverse effect on our results of operations in a particular quarter or year if such resolution results in liability that materially exceeds the accrued amount.

In addition, we have other litigation matters pending for which we have not recorded any accruals because our potential liability for those matters is not probable or cannot be reasonably estimated based on currently available information. For those matters where we have not recorded an accrual but a loss is reasonably possible, we cannot determine a reasonable estimate of the maximum possible loss or range of loss for these matters given that they are at various stages of the litigation process and each case is subject to the inherent uncertainties of litigation (such as the strength of our legal defenses and the availability of insurance recovery). Although the maximum amount of liability that may ultimately result from any of these matters cannot be predicted with absolute certainty, management expects that none of the matters for which we have not recorded an accrual, when ultimately resolved, will have a material adverse effect on our consolidated financial position or liquidity. It is possible, however, that the ultimate resolution of one or more of these matters could have a material adverse effect on our results of operations in a particular quarter or year if such resolution results in a significant liability for GATX.

Environmental

Our operations are subject to extensive federal, state, and local environmental regulations. Our operating procedures include practices to protect the environment from the risks inherent in full service railcar leasing, which involves maintaining railcars used by customers to transport chemicals and other hazardous materials. Under some environmental laws in the U.S. and certain other countries, the owner of a leased railcar may be liable for environmental damage and cleanup or other costs in the event of a spill or discharge of material from a railcar without regard to the owner's fault. While our standard master railcar lease agreement requires the lessee to indemnify us against environmental claims and to carry liability insurance coverage, such indemnities and insurance may not fully protect us against claims for environmental damage. Additionally, some of our real estate holdings, including previously owned properties, are or have been used for industrial or transportation-related purposes or leased to commercial or industrial companies whose activities might have resulted in discharges on the property. As a result, we are subject to environmental cleanup and enforcement actions. In particular, the federal Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”), also known as the Superfund law, as well as similar state laws, impose joint and several liability for cleanup and enforcement costs on current and former owners and operators of a site without regard to fault or the legality of the original conduct. If there are other potentially responsible parties (“PRPs”), we generally contribute to the cleanup of these sites through cost-sharing agreements with terms that vary from site to site. Costs are typically allocated based on the relative volumetric contribution of material, the period of time the site was owned or operated, and/or the portion of the site owned or operated by each PRP.

At the time a potential environmental issue is identified, initial accruals for environmental liability are established when such liability is determined to be probable and a reasonable estimate of the associated costs can be made. Costs are estimated based on the type and level of investigation and/or remediation activities that our internal environmental staff (and where appropriate, independent consultants) have advised to be necessary to comply with applicable laws and regulations. Activities include surveys and environmental studies of potentially contaminated sites as well as costs for remediation and restoration of sites determined to be contaminated. In addition, we have provided indemnities for potential environmental liabilities to buyers of divested companies. In these instances, accruals are based on the scope and duration of the respective indemnities together with the extent of known contamination. Estimates are periodically reviewed and adjusted as required to reflect additional information about facility or site characteristics or changes in regulatory requirements. We conduct a quarterly environmental contingency analysis, which considers a combination of factors including independent consulting reports, site visits, legal reviews, analysis of the likelihood of participation in and the ability of other PRPs to pay for cleanup, and historical trend analyses.

We are involved in administrative and judicial proceedings and other voluntary and mandatory cleanup efforts at 13 sites, including Superfund sites, for which we are contributing to the cost of performing the study or cleanup, or both, of alleged environmental contamination. As of December 31, 2018, we have recorded accruals of $13.7 million for remediation and restoration costs that we believe to be probable and for which the amount of loss can be reasonably estimated. These amounts are included in other liabilities on our balance sheet. Our environmental liabilities are not discounted.

We did not materially change our methodology for identifying and calculating environmental liabilities in the last three years. Currently, no known trends, demands, commitments, events or uncertainties exist that are reasonably likely to occur and materially affect the methodology or assumptions described above.

The recorded accruals represent our best estimate of all costs for remediation and restoration of affected sites, without reduction for anticipated recoveries from third parties, and include both asserted and unasserted claims. However, we are unable to provide a reasonable estimate of the maximum potential loss associated with these sites because cleanup costs cannot be predicted with certainty. Various factors beyond our control can impact the amount of loss GATX will ultimately incur with respect to these sites, including the extent of corrective actions that may be required; evolving environmental laws and regulations; advances in environmental technology, the extent of other parties' participation in cleanup efforts; developments in periodic environmental analyses related to sites determined to be contaminated, and developments in environmental surveys and studies of potentially contaminated sites. As a result, future charges associated with these sites could have a significant effect on results of operations in a particular quarter or year if the costs materially exceed the accrued amount as individual site studies and remediation and restoration efforts proceed. However, management believes it is unlikely that the ultimate cost to GATX for any of these sites, either individually or in the aggregate, will have a material adverse effect on our consolidated financial position or liquidity.