Summary of Accounting Policies	12 Months Ended
Dec. 31, 2014
Accounting Policies [Abstract]
Summary of Accounting Policies	Summary of Accounting Policies Cash and cash equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Revenue recognition Revenues from manufactured railcar sales are recognized following completion of manufacturing, inspection, customer acceptance and title transfer, which is when the risk for any damage or loss with respect to the railcars passes to the customer. Amounts billed prior to meeting revenue recognition criteria are accounted for in Deferred revenue on the consolidated balance sheets. Revenues from railcar leasing are recognized on a straight-line basis per terms of the lease. If railcars are sold under a lease that is less than one year old, the proceeds from the railcars sold that were on lease will be shown on a gross basis in revenues and cost of revenues at the time of sale. Sales of leased railcars that have been on lease for more than one year are recognized as a net gain or loss from the disposal of the long-term asset as a component of earnings from operations. Revenues from railcar and industrial components are recorded at the time of product shipment, in accordance with the Company's contractual terms. Revenues from railcar maintenance services are recognized upon completion. The Company does not currently bundle railcar service contracts with new railcar sales. Revenues from engineering and field services are recognized as performed. The Company records amounts billed to customers for shipping and handling as part of sales and records related costs in cost of revenues. ARI presents any sales tax assessed by a governmental authority that is directly imposed on a revenue-producing transaction between a seller and a customer on a net basis. Accounts receivable, net On a routine basis, the Company evaluates its accounts receivable and establishes an allowance for doubtful accounts based on the history of past write-offs and collections and current credit conditions. Accounts are placed for collection on a limited basis once all other methods of collection have been exhausted. When it has been determined that the customer is no longer in business and/or refuses to pay, the accounts are written off. Inventories, net Inventories are stated at the lower of cost or market on a first-in, first-out basis, and include the cost of materials, direct labor and manufacturing overhead. The Company allocates fixed production overheads to the costs of conversion based on the normal capacity of its production facilities. If any of the Company's production facilities are operating below normal capacity, unallocated production overheads are recognized as a current period charge. Property, plant, equipment, and railcars on leases, net Land, buildings, machinery, equipment, and railcars on operating leases are carried at cost, which could include capitalized interest on borrowed funds. Maintenance and repair costs are charged directly to earnings. Tooling is generally capitalized and depreciated over a period of approximately five years. Internally developed software is capitalized and amortized over a period ranging from five to ten years. Buildings are depreciated over estimated useful lives that range from 15 to 39 years. The estimated useful lives of other depreciable assets, including machinery, equipment and leased railcars vary from 3 to 30 years. Depreciation is calculated using the straight-line method for financial reporting purposes and on accelerated methods for tax purposes. Impairment of long-lived assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of assets may not be recoverable. The Company has determined that there were no triggering events that required an assessment for impairment of long-lived assets, therefore no impairment charges were recognized during any of the years presented. The criteria for determining impairment of such long-lived assets to be held and used is determined by comparing the carrying value of these long-lived assets to be held and used to management's best estimate of future undiscounted cash flows expected to result from the use of the long-lived assets. If the long-lived assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the long-lived assets exceeds the fair value of the long-lived assets. The estimated fair value of long-lived assets is measured by estimating the present value of the future discounted cash flows to be generated. Debt issuance costs Debt issuance costs were incurred in connection with ARI's issuance of debt under its lease fleet financing facilities as described in Note 12, and are amortized over the term of the related debt. Goodwill Goodwill is not amortized but is reviewed for impairment at least annually, on March 1, or as events or changes in circumstances indicate that the carrying amount may not be recoverable. The review for impairment is either a qualitative assessment or a two-step process. If the Company chooses to perform a qualitative assessment by assessing qualitative factors to determine if any potential impairment exists and determine that the fair value of the reporting unit more likely than not exceeds the carrying value, no further evaluation is necessary. For the two-step process, the first step is to compare the estimated fair value of the operating unit with the recorded net book value (including the goodwill). The detailed test is performed by first comparing the carrying value of the reporting unit, including goodwill to its fair value. The fair value of the reporting unit is determined using a combination of methods including prices of comparable businesses using recent transactions involving businesses similar to the Company and a present value technique, referred to as the market and income approaches, respectively. If the estimated fair value of the operating unit is higher than the recorded net book value, no impairment is deemed to exist and no further testing is required. If, however, the estimated fair value of the operating unit is below the recorded net book value, then a second step must be performed to determine if impairment of the goodwill is required. In this second step, the implied fair value of goodwill is calculated as the excess of the fair value of the operating unit over the fair value assigned to the operating unit's assets and liabilities. If the implied fair value of goodwill is less than the book value of the goodwill, the difference is recognized as an impairment loss. See Note 9 for further discussion on this analysis. Investment in and loans to joint ventures The Company uses the equity method to account for its investments in various joint ventures as described in Note 10. Under the equity method, the Company recognizes its share of the earnings and losses of the joint ventures as they accrue. Advances and distributions are charged and credited directly to the investment account. From time to time, the Company also makes loans to its joint ventures that are included in the investment account. Income taxes ARI accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial reporting basis and the tax basis of ARI's assets and liabilities at enacted tax rates expected to be in effect when such amounts are recovered or settled. ARI regularly evaluates recoverability of its deferred tax assets and establishes a valuation allowance, if necessary, based on historical taxable income, projected future taxable income, the expected timing of the reversals of existing temporary differences and the implementation of tax-planning strategies. The Company also records unrecognized tax positions, including potential interest and penalties as income tax expense. For further discussion of income taxes refer to Note 13. Pension plans and other postretirement benefits Certain ARI employees participate in noncontributory, defined benefit pension plans and a supplemental executive retirement plan. Benefits for the salaried employees are based on salary and years of service, while those for hourly employees are based on negotiated rates and years of service. ARI also previously sponsored a retiree health care plan covering certain employees. Benefit costs accrued during the years employees render service. The retiree medical plan was terminated effective December 31, 2013. ARI also sponsors a defined contribution retirement plan. For further discussion of employee benefit plans refer to Note 14. Foreign currency translation Balance sheet amounts from the Company's Canadian operations are translated at the exchange rate effective at year-end and the statement of operations amounts are translated at the average rate of exchange prevailing during the year. Currency translation adjustments are included in stockholders' equity as part of accumulated other comprehensive income (loss). Comprehensive income Comprehensive income is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income consists of net earnings, foreign currency translation, changes resulting from realized and unrealized gains and losses related to postretirement liability transactions and changes resulting from realized and unrealized gains and losses on short-term investments or derivative instruments for which hedge accounting is being applied. All components of comprehensive income are shown net of tax. Earnings per common share Basic earnings per common share is calculated as net earnings attributable to common stockholders divided by the weighted-average number of common shares outstanding during the respective period. Diluted earnings per common share is calculated by dividing net earnings attributable to common stockholders by the weighted-average common number of shares outstanding plus dilutive potential common shares outstanding during the year. Use of estimates ARI has made a number of estimates and assumptions relating to the reporting of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities to prepare these financial statements in conformity with accounting principles generally accepted in the United States of America. Significant items subject to estimates and assumptions include, but are not limited to, deferred taxes, workers' compensation accrual, valuation allowances for accounts receivable and inventory obsolescence, depreciable lives of assets, goodwill impairment, share-based compensation fair values, the reserve for warranty claims and revenues recognized under the proportional performance method. Actual results could differ from those estimates. Share-based compensation The share-based compensation cost recorded for stock appreciation rights (SARs) is based on their fair value. For further discussion of share-based compensation refer to Note 16. Reclassifications Certain prior-period amounts on the consolidated financial statements and in the notes to the consolidated financial statements have been reclassified to conform to current-period presentation. There have been no material reclassifications during the current period.

Summary of Accounting Policies

Cash and cash equivalents

The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents.

Revenue recognition

Revenues from manufactured railcar sales are recognized following completion of manufacturing, inspection, customer acceptance and title transfer, which is when the risk for any damage or loss with respect to the railcars passes to the customer. Amounts billed prior to meeting revenue recognition criteria are accounted for in Deferred revenue on the consolidated balance sheets. Revenues from railcar leasing are recognized on a straight-line basis per terms of the lease. If railcars are sold under a lease that is less than one year old, the proceeds from the railcars sold that were on lease will be shown on a gross basis in revenues and cost of revenues at the time of sale. Sales of leased railcars that have been on lease for more than one year are recognized as a net gain or loss from the disposal of the long-term asset as a component of earnings from operations. Revenues from railcar and industrial components are recorded at the time of product shipment, in accordance with the Company's contractual terms. Revenues from railcar maintenance services are recognized upon completion. The Company does not currently bundle railcar service contracts with new railcar sales. Revenues from engineering and field services are recognized as performed.

The Company records amounts billed to customers for shipping and handling as part of sales and records related costs in cost of revenues.

ARI presents any sales tax assessed by a governmental authority that is directly imposed on a revenue-producing transaction between a seller and a customer on a net basis.

Accounts receivable, net

On a routine basis, the Company evaluates its accounts receivable and establishes an allowance for doubtful accounts based on the history of past write-offs and collections and current credit conditions. Accounts are placed for collection on a limited basis once all other methods of collection have been exhausted. When it has been determined that the customer is no longer in business and/or refuses to pay, the accounts are written off.

Inventories, net

Inventories are stated at the lower of cost or market on a first-in, first-out basis, and include the cost of materials, direct labor and manufacturing overhead. The Company allocates fixed production overheads to the costs of conversion based on the normal capacity of its production facilities. If any of the Company's production facilities are operating below normal capacity, unallocated production overheads are recognized as a current period charge.

Property, plant, equipment, and railcars on leases, net

Land, buildings, machinery, equipment, and railcars on operating leases are carried at cost, which could include capitalized interest on borrowed funds. Maintenance and repair costs are charged directly to earnings. Tooling is generally capitalized and depreciated over a period of approximately five years. Internally developed software is capitalized and amortized over a period ranging from five to ten years.

Buildings are depreciated over estimated useful lives that range from 15 to 39 years. The estimated useful lives of other depreciable assets, including machinery, equipment and leased railcars vary from 3 to 30 years. Depreciation is calculated using the straight-line method for financial reporting purposes and on accelerated methods for tax purposes.

Impairment of long-lived assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of assets may not be recoverable. The Company has determined that there were no triggering events that required an assessment for impairment of long-lived assets, therefore no impairment charges were recognized during any of the years presented.

The criteria for determining impairment of such long-lived assets to be held and used is determined by comparing the carrying value of these long-lived assets to be held and used to management's best estimate of future undiscounted cash flows expected to result from the use of the long-lived assets. If the long-lived assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the long-lived assets exceeds the fair value of the long-lived assets. The estimated fair value of long-lived assets is measured by estimating the present value of the future discounted cash flows to be generated.

Debt issuance costs

Debt issuance costs were incurred in connection with ARI's issuance of debt under its lease fleet financing facilities as described in Note 12, and are amortized over the term of the related debt.

Goodwill

Goodwill is not amortized but is reviewed for impairment at least annually, on March 1, or as events or changes in circumstances indicate that the carrying amount may not be recoverable. The review for impairment is either a qualitative assessment or a two-step process. If the Company chooses to perform a qualitative assessment by assessing qualitative factors to determine if any potential impairment exists and determine that the fair value of the reporting unit more likely than not exceeds the carrying value, no further evaluation is necessary.

For the two-step process, the first step is to compare the estimated fair value of the operating unit with the recorded net book value (including the goodwill). The detailed test is performed by first comparing the carrying value of the reporting unit, including goodwill to its fair value. The fair value of the reporting unit is determined using a combination of methods including prices of comparable businesses using recent transactions involving businesses similar to the Company and a present value technique, referred to as the market and income approaches, respectively. If the estimated fair value of the operating unit is higher than the recorded net book value, no impairment is deemed to exist and no further testing is required. If, however, the estimated fair value of the operating unit is below the recorded net book value, then a second step must be performed to determine if impairment of the goodwill is required. In this second step, the implied fair value of goodwill is calculated as the excess of the fair value of the operating unit over the fair value assigned to the operating unit's assets and liabilities. If the implied fair value of goodwill is less than the book value of the goodwill, the difference is recognized as an impairment loss. See Note 9 for further discussion on this analysis.

Investment in and loans to joint ventures

The Company uses the equity method to account for its investments in various joint ventures as described in Note 10. Under the equity method, the Company recognizes its share of the earnings and losses of the joint ventures as they accrue. Advances and distributions are charged and credited directly to the investment account. From time to time, the Company also makes loans to its joint ventures that are included in the investment account.

Income taxes

ARI accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial reporting basis and the tax basis of ARI's assets and liabilities at enacted tax rates expected to be in effect when such amounts are recovered or settled. ARI regularly evaluates recoverability of its deferred tax assets and establishes a valuation allowance, if necessary, based on historical taxable income, projected future taxable income, the expected timing of the reversals of existing temporary differences and the implementation of tax-planning strategies. The Company also records unrecognized tax positions, including potential interest and penalties as income tax expense. For further discussion of income taxes refer to Note 13.

Pension plans and other postretirement benefits

Certain ARI employees participate in noncontributory, defined benefit pension plans and a supplemental executive retirement plan. Benefits for the salaried employees are based on salary and years of service, while those for hourly employees are based on negotiated rates and years of service.

ARI also previously sponsored a retiree health care plan covering certain employees. Benefit costs accrued during the years employees render service. The retiree medical plan was terminated effective December 31, 2013.

ARI also sponsors a defined contribution retirement plan. For further discussion of employee benefit plans refer to Note 14.

Foreign currency translation

Balance sheet amounts from the Company's Canadian operations are translated at the exchange rate effective at year-end and the statement of operations amounts are translated at the average rate of exchange prevailing during the year. Currency translation adjustments are included in stockholders' equity as part of accumulated other comprehensive income (loss).

Comprehensive income

Comprehensive income is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income consists of net earnings, foreign currency translation, changes resulting from realized and unrealized gains and losses related to postretirement liability transactions and changes resulting from realized and unrealized gains and losses on short-term investments or derivative instruments for which hedge accounting is being applied. All components of comprehensive income are shown net of tax.

Earnings per common share

Basic earnings per common share is calculated as net earnings attributable to common stockholders divided by the weighted-average number of common shares outstanding during the respective period. Diluted earnings per common share is calculated by dividing net earnings attributable to common stockholders by the weighted-average common number of shares outstanding plus dilutive potential common shares outstanding during the year.

Use of estimates

ARI has made a number of estimates and assumptions relating to the reporting of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities to prepare these financial statements in conformity with accounting principles generally accepted in the United States of America. Significant items subject to estimates and assumptions include, but are not limited to, deferred taxes, workers' compensation accrual, valuation allowances for accounts receivable and inventory obsolescence, depreciable lives of assets, goodwill impairment, share-based compensation fair values, the reserve for warranty claims and revenues recognized under the proportional performance method. Actual results could differ from those estimates.

Share-based compensation

The share-based compensation cost recorded for stock appreciation rights (SARs) is based on their fair value. For further discussion of share-based compensation refer to Note 16.

Reclassifications

Certain prior-period amounts on the consolidated financial statements and in the notes to the consolidated financial statements have been reclassified to conform to current-period presentation. There have been no material reclassifications during the current period.