Basis of Presentation Basis of Presentation (Policies)	6 Months Ended
Jun. 30, 2018
Basis of Presentation [Abstract]
Basis of Presentation [Policy Text Block]	Basis of Presentation and New Accounting Pronouncements Heartland Express, Inc. (the “Company,” “we,” “us,” or “our”), is a holding company incorporated in Nevada, which owns all of the stock of Heartland Express, Inc. of Iowa, Heartland Express Services, Inc., Heartland Express Maintenance Services, Inc., and A & M Express, Inc. Following the acquisition of Interstate Distributor Co. ("IDC") on July 6, 2017, IDC was subsequently merged into Heartland Express, Inc. of Iowa effective October 1, 2017 as was Gordon Trucking, Inc. ("GTI") effective July 1, 2016. We, and our subsidiaries, operate as one segment. We, together with our subsidiaries, are a short-to-medium haul truckload carrier (predominately 500 miles or less per load) with corporate headquarters in North Liberty, Iowa. We primarily provide nationwide asset-based dry van truckload service for major shippers from Washington to Florida and New England to California. The accompanying consolidated financial statements include the parent company, Heartland Express, Inc., and its subsidiaries, all of which are wholly owned. The consolidated financial results for the three and six months ended June 30, 2018, include the acquired assets and operating results of IDC while the consolidated financial results for the three and six months ended June 30, 2017 do not. All material intercompany items and transactions have been eliminated in consolidation. The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial information and with the instructions to Form 10-Q and Regulation S-X. Accordingly, they do not include all of the information and notes to the financial statements required by U.S. GAAP for complete financial statements. In the opinion of management, all normal, recurring adjustments considered necessary for a fair presentation have been included. The consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes for the year ended December 31, 2017 included in the Annual Report on Form 10-K of the Company filed with the Securities and Exchange Commission on March 1, 2018. Interim results of operations are not necessarily indicative of the results to be expected for the full year or any other interim periods.
New Accounting Pronouncements, Policy [Policy Text Block]	In March 2018, the Financial Accounting Standards Boards (FASB) issued ASU 2018-05, "Income Taxes (Topic 740) which provides for amendments to the SEC issued Staff Accounting Bulletin (“SAB 118”), which provides guidance on accounting for tax effects of the Tax Act. ASU 2018-05 and SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740. In accordance with ASU 2018-05 and SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate to be included in the financial statements. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply ASC 740 on the basis of the provision of the tax laws that were in effect immediately before the enactment of the Tax Act. Management has evaluated the relevant provisions of the Tax Act to the Company and accounted for the federal impacts in the financial statements as of June 30, 2018. The state tax provisional amount is subject to change based on how states conform to the Tax Act, as that information is not readily available for certain states at this time. Any revisions to the estimated impacts of the Tax Act will be recorded quarterly until the computations are complete, which is expected to be no later than the fourth quarter of 2018. In May 2017, the FASB issued ASU 2017-09, "Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting," to provide clarity and reduce diversity and complexity of applying the accounting guidance in Topic 718 to a change in the terms or conditions of a share-based payment award. An entity should account for the effects of a modification unless certain criteria are met. The provisions of this update are effective for interim and annual periods beginning after December 15, 2017. We have adopted this standard prospectively for interim and annual periods beginning January 1, 2018. The adoption of this standard did not have a material impact on our consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment,” which continues to require an entity to review indicators for impairment, perform qualitative assessments, and analyze the fair value of a reporting unit as compared to the carrying value of goodwill for potential impairment, but eliminates or replaces additional tests and assessments within the prior guidance. The provisions of this update are effective for fiscal years beginning after December 15, 2019, with early adoption permitted for impairment measurement tests occurring after January 1, 2017. Based on our initial assessment, we believe the impact of adoption of the standard will not have a material impact on our financial statements but we have not determined our date of adoption at this time. In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash,” which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash. The provisions of this update are effective for fiscal years beginning after December 15, 2017 and we have adopted this standard using the required retrospective adoption method. The adoption of this standard impacted the consolidated statements of cash flows by increasing beginning and ending cash and cash equivalents presented to include our restricted cash balances. The changes in restricted cash are presented within investing activities eliminating the change in designated funds for equipment purchases and change in designated funds for claims liabilities line items. The overall impact of the change was an increase to investing cash flows $2.7 million for the six months ended June 30, 2017. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments,” which addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice. The provisions of this update are effective for fiscal years beginning after December 15, 2017 and we have adopted this standard prospectively for interim and annual periods beginning January 1, 2018. The adoption of this standard did not have any impact on our consolidated statement of cash flows. In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments". This update requires measurement and recognition of expected versus incurred credit losses for financial assets held. ASU 2016-13 is effective for annual periods beginning after December 15, 2019, and interim periods therein. Based on our initial assessment, we believe the impact of adoption of the standard will not have a material impact on our financial statements. In February 2016, the FASB issued ASU 2016-02, "Leases". This update seeks to increase the transparency and comparability among entities by requiring public entities to recognize lease assets and lease liabilities on the balance sheet and disclose key information about leasing arrangements. To satisfy the standard’s objective, a lessee will recognize a right-of-use asset representing its right to use the underlying asset for the lease term and a lease liability for the obligation to make lease payments. Both the right-of-use asset and lease liability will initially be measured at the present value of the lease payments, with subsequent measurement dependent on the classification of the lease as either a finance or an operating lease. For leases with a term of twelve months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it should recognize lease expense for such leases generally on a straight-line basis over the lease term. In transition, lessees are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that companies may elect to apply. These practical expedients relate to the identification and classification of leases that commenced before the effective date, initial direct costs for leases that commenced before the effective date, and the ability to use hindsight in evaluating lessee options to extend or terminate a lease or to purchase the underlying asset. The transition guidance also provides specific guidance for sale and leaseback transactions, build-to-suit leases, leveraged leases, and amounts previously recognized in accordance with the business combinations guidance for leases. The new standard is effective for public companies for annual periods beginning after December 15, 2018, and interim periods within those years, with early adoption permitted. We continue to evaluate our changing portfolio of leases and we expect to complete an updated assessment and select a transition method by January 1, 2019, our selected date of transition. In May 2014, the FASB issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers (Topic 606), which will replace numerous requirements in U.S. GAAP, including industry-specific requirements, and provide companies with a single revenue recognition model for recognizing revenue from contracts with customers. The core principle of the new standard is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. The two permitted transition methods under the new standard are the full retrospective method, in which case the standard would be applied to each prior reporting period presented and the cumulative effect of applying the standard would be recognized at the earliest period shown, or the modified retrospective method, in which case the cumulative effect of applying the standard would be recognized at the date of initial application. In July 2015, the FASB approved the deferral of the new standard's effective date by one year. The new standard is effective for annual reporting periods beginning after December 15, 2017. We have selected and have implemented the modified cumulative-effect transition method at January 1, 2018, our date of adoption. The effect of adoption was immaterial to retained earnings at January 1, 2018 and to net income for the three and six month period ended June 30, 2018. See additional discussions on revenue recognition at Note 4.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Segment Reporting, Policy [Policy Text Block]	Segment Information We provide truckload services across the United States (U.S.) and parts of Canada. These truckload services are primarily asset-based transportation services in the dry van truckload market, and we also offer truckload temperature-controlled transportation services and have previously offered non-asset based brokerage services, neither of which are significant to our operations. We exited our non-asset-based freight brokerage business in the first quarter of 2017, then operated similar services following the acquisition of IDC until the fourth quarter of 2017. Our Chief Operating Decision Maker oversees and manages all of our transportation services, on a combined basis, including previously acquired entities. As a result of the foregoing, we have determined that we have one segment, consistent with the authoritative accounting guidance on disclosures about segments of an enterprise and related information.
Revenue Recognition, Policy [Policy Text Block]	The Company generates revenue from transportation services under contracts with customers, generally on a rate per mile or per shipment, based on origin and destination of the shipment. The Company’s performance obligation arises when it accepts a shipment order to transport a customer’s freight and is satisfied upon delivery of the shipment. The transaction price may be defined in a transportation services agreement or negotiated with the customer prior to accepting the shipment order. A customer may submit several shipment orders for transportation services at various times throughout a service agreement term, but each shipment represents a distinct service that is a separately identified performance obligation. The Company often provides additional accessorial and other services as part of the shipment (including but not limited to loading/unloading, stops in transit, and tractor and trailer detention) which are not distinct or are not material in the context of the contract; therefore the revenue for these services is recognized with the freight transaction price. Fuel surcharge revenue consists of additional fees earned by the Company in connection with the performance of line haul services to partially or completely offset the cost of fuel. The Company also provided non-asset based brokerage services recorded as other revenue during the three and six months ended June 30, 2017 before these services were ended in late 2017. Revenues are recognized over time as control of the promised services is transferred to our customers, in an amount that reflects the consideration we expect to be entitled to in exchange for those services. Revenue is estimated for multiple-stop loads based on miles run and estimated for single stop loads based on transit time, as the customer simultaneously receives and consumes the benefit provided. Revenue associated with loads delivered but not billed as of the end of an accounting period are also estimated as part of revenue for that period. Revenue recognition methods described align with the recognition of our associated expenses in the statement of comprehensive income.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents Cash equivalents are short-term, highly liquid investments with insignificant interest rate risk and original maturities of three months or less at acquisition.
Property, Plant and Equipment, Policy [Policy Text Block]	Prepaid Tires, Property, Equipment, and Depreciation Property and equipment are reported at cost, net of accumulated depreciation. Maintenance and repairs are charged to operations as incurred. New tires are capitalized separately from revenue equipment and are reported separately as “Prepaid tires” in the consolidated balance sheets and amortized over two years. Depreciation for financial statement purposes is computed by the straight-line method for all assets other than tractors. We recognize depreciation expense on tractors using the 125% declining balance method. New tractors are depreciated to salvage values of $15,000 while new trailers are depreciated to salvage values of $4,000.
Earnings Per Share, Policy [Policy Text Block]	Earnings per Share Basic earnings per share is based upon the weighted average common shares outstanding during each year. Diluted earnings per share is based on the basic weighted earnings per share with additional weighted common shares for common stock equivalents.
Income Tax, Policy [Policy Text Block]	Income Taxes We use the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Such amounts are adjusted, as appropriate, to reflect changes in tax rates expected to be in effect when temporary differences reverse. The effect of a change in tax rates on deferred taxes is recognized in the period that the change is enacted. A valuation allowance is recorded to reduce the Company's deferred tax assets to the amount that is more likely than not to be realized.
Income Tax Uncertainties, Policy [Policy Text Block]	We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. We record interest and penalties related to unrecognized tax benefits in income tax expense.
Subsequent Events, Policy [Policy Text Block]	Subsequent Events No events occurred requiring disclosure other than the repurchase of an additional 0.2 million shares of our common stock for $4.2 million subsequent to June 30, 2018.

Basis of Presentation Basis of Presentation (Policies)

6 Months Ended

Jun. 30, 2018

Basis of Presentation [Policy Text Block]

Basis of Presentation and New Accounting Pronouncements

Heartland Express, Inc. (the “Company,” “we,” “us,” or “our”), is a holding company incorporated in Nevada, which owns all of the stock of Heartland Express, Inc. of Iowa, Heartland Express Services, Inc., Heartland Express Maintenance Services, Inc., and A & M Express, Inc. Following the acquisition of Interstate Distributor Co. ("IDC") on July 6, 2017, IDC was subsequently merged into Heartland Express, Inc. of Iowa effective October 1, 2017 as was Gordon Trucking, Inc. ("GTI") effective July 1, 2016. We, and our subsidiaries, operate as one segment. We, together with our subsidiaries, are a short-to-medium haul truckload carrier (predominately 500 miles or less per load) with corporate headquarters in North Liberty, Iowa. We primarily provide nationwide asset-based dry van truckload service for major shippers from Washington to Florida and New England to California.

The accompanying consolidated financial statements include the parent company, Heartland Express, Inc., and its subsidiaries, all of which are wholly owned. The consolidated financial results for the three and six months ended June 30, 2018, include the acquired assets and operating results of IDC while the consolidated financial results for the three and six months ended June 30, 2017 do not. All material intercompany items and transactions have been eliminated in consolidation. The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial information and with the instructions to Form 10-Q and Regulation S-X. Accordingly, they do not include all of the information and notes to the financial statements required by U.S. GAAP for complete financial statements. In the opinion of management, all normal, recurring adjustments considered necessary for a fair presentation have been included. The consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes for the year ended December 31, 2017 included in the Annual Report on Form 10-K of the Company filed with the Securities and Exchange Commission on March 1, 2018. Interim results of operations are not necessarily indicative of the results to be expected for the full year or any other interim periods.

New Accounting Pronouncements, Policy [Policy Text Block]

In March 2018, the Financial Accounting Standards Boards (FASB) issued ASU 2018-05, "Income Taxes (Topic 740) which provides for amendments to the SEC issued Staff Accounting Bulletin (“SAB 118”), which provides guidance on accounting for tax effects of the Tax Act. ASU 2018-05 and SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740. In accordance with ASU 2018-05 and SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate to be included in the financial statements. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply ASC 740 on the basis of the provision of the tax laws that were in effect immediately before the enactment of the Tax Act. Management has evaluated the relevant provisions of the Tax Act to the Company and accounted for the federal impacts in the financial statements as of June 30, 2018. The state tax provisional amount is subject to change based on how states conform to the Tax Act, as that information is not readily available for certain states at this time. Any revisions to the estimated impacts of the Tax Act will be recorded quarterly until the computations are complete, which is expected to be no later than the fourth quarter of 2018.

In May 2017, the FASB issued ASU 2017-09, "Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting," to provide clarity and reduce diversity and complexity of applying the accounting guidance in Topic 718 to a change in the terms or conditions of a share-based payment award. An entity should account for the effects of a modification unless certain criteria are met. The provisions of this update are effective for interim and annual periods beginning after December 15, 2017. We have adopted this standard prospectively for interim and annual periods beginning January 1, 2018. The adoption of this standard did not have a material impact on our consolidated financial statements.

In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment,” which continues to require an entity to review indicators for impairment, perform qualitative assessments, and analyze the fair value of a reporting unit as compared to the carrying value of goodwill for potential impairment, but eliminates or replaces additional tests and assessments within the prior guidance. The provisions of this update are effective for fiscal years beginning after December 15, 2019, with early adoption permitted for impairment measurement tests occurring after January 1, 2017. Based on our initial assessment, we believe the impact of adoption of the standard will not have a material impact on our financial statements but we have not determined our date of adoption at this time.

In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash,” which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash. The provisions of this update are effective for fiscal years beginning after December 15, 2017 and we have adopted this standard using the required retrospective adoption method. The adoption of this standard impacted the consolidated statements of cash flows by increasing beginning and ending cash and cash equivalents presented to include our restricted cash balances. The changes in restricted cash are presented within investing activities eliminating the change in designated funds for equipment purchases and change in designated funds for claims liabilities line items. The overall impact of the change was an increase to investing cash flows $2.7 million for the six months ended June 30, 2017.

In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments,” which addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice. The provisions of this update are effective for fiscal years beginning after December 15, 2017 and we have adopted this standard prospectively for interim and annual periods beginning January 1, 2018. The adoption of this standard did not have any impact on our consolidated statement of cash flows.

In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments". This update requires measurement and recognition of expected versus incurred credit losses for financial assets held. ASU 2016-13 is effective for annual periods beginning after December 15, 2019, and interim periods therein. Based on our initial assessment, we believe the impact of adoption of the standard will not have a material impact on our financial statements.

In February 2016, the FASB issued ASU 2016-02, "Leases". This update seeks to increase the transparency and comparability among entities by requiring public entities to recognize lease assets and lease liabilities on the balance sheet and disclose key information about leasing arrangements. To satisfy the standard’s objective, a lessee will recognize a right-of-use asset representing its right to use the underlying asset for the lease term and a lease liability for the obligation to make lease payments. Both the right-of-use asset and lease liability will initially be measured at the present value of the lease payments, with subsequent measurement dependent on the classification of the lease as either a finance or an operating lease. For leases with a term of twelve months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it should recognize lease expense for such leases generally on a straight-line basis over the lease term.

In transition, lessees are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that companies may elect to apply. These practical expedients relate to the identification and classification of leases that commenced before the effective date, initial direct costs for leases that commenced before the effective date, and the ability to use hindsight in evaluating lessee options to extend or terminate a lease or to purchase the underlying asset. The transition guidance also provides specific guidance for sale and leaseback transactions, build-to-suit leases, leveraged leases, and amounts previously recognized in accordance with the business combinations guidance for leases. The new standard is effective for public companies for annual periods beginning after December 15, 2018, and interim periods within those years, with early adoption permitted. We continue to evaluate our changing portfolio of leases and we expect to complete an updated assessment and select a transition method by January 1, 2019, our selected date of transition.

In May 2014, the FASB issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers (Topic 606), which will replace numerous requirements in U.S. GAAP, including industry-specific requirements, and provide companies with a single revenue recognition model for recognizing revenue from contracts with customers. The core principle of the new standard is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. The two permitted transition methods under the new standard are the full retrospective method, in which case the standard would be applied to each prior reporting period presented and the cumulative effect of applying the standard would be recognized at the earliest period shown, or the modified retrospective method, in which case the cumulative effect of applying the standard would be recognized at the date of initial application. In July 2015, the FASB approved the deferral of the new standard's effective date by one year. The new standard is effective for annual reporting periods beginning after December 15, 2017. We have selected and have implemented the modified cumulative-effect transition method at January 1, 2018, our date of adoption. The effect of adoption was immaterial to retained earnings at January 1, 2018 and to net income for the three and six month period ended June 30, 2018. See additional discussions on revenue recognition at Note 4.

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Segment Reporting, Policy [Policy Text Block]

Segment Information

We provide truckload services across the United States (U.S.) and parts of Canada. These truckload services are primarily asset-based transportation services in the dry van truckload market, and we also offer truckload temperature-controlled transportation services and have previously offered non-asset based brokerage services, neither of which are significant to our operations. We exited our non-asset-based freight brokerage business in the first quarter of 2017, then operated similar services following the acquisition of IDC until the fourth quarter of 2017. Our Chief Operating Decision Maker oversees and manages all of our transportation services, on a combined basis, including previously acquired entities. As a result of the foregoing, we have determined that we have one segment, consistent with the authoritative accounting guidance on disclosures about segments of an enterprise and related information.

Revenue Recognition, Policy [Policy Text Block]

The Company generates revenue from transportation services under contracts with customers, generally on a rate per mile or per shipment, based on origin and destination of the shipment. The Company’s performance obligation arises when it accepts a shipment order to transport a customer’s freight and is satisfied upon delivery of the shipment. The transaction price may be defined in a transportation services agreement or negotiated with the customer prior to accepting the shipment order. A customer may submit several shipment orders for transportation services at various times throughout a service agreement term, but each shipment represents a distinct service that is a separately identified performance obligation. The Company often provides additional accessorial and other services as part of the shipment (including but not limited to loading/unloading, stops in transit, and tractor and trailer detention) which are not distinct or are not material in the context of the contract; therefore the revenue for these services is recognized with the freight transaction price. Fuel surcharge revenue consists of additional fees earned by the Company in connection with the performance of line haul services to partially or completely offset the cost of fuel. The Company also provided non-asset based brokerage services recorded as other revenue during the three and six months ended June 30, 2017 before these services were ended in late 2017.

Revenues are recognized over time as control of the promised services is transferred to our customers, in an amount that reflects the consideration we expect to be entitled to in exchange for those services. Revenue is estimated for multiple-stop loads based on miles run and estimated for single stop loads based on transit time, as the customer simultaneously receives and consumes the benefit provided. Revenue associated with loads delivered but not billed as of the end of an accounting period are also estimated as part of revenue for that period. Revenue recognition methods described align with the recognition of our associated expenses in the statement of comprehensive income.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents

Cash equivalents are short-term, highly liquid investments with insignificant interest rate risk and original maturities of three months or less at acquisition.

Property, Plant and Equipment, Policy [Policy Text Block]

Prepaid Tires, Property, Equipment, and Depreciation

Property and equipment are reported at cost, net of accumulated depreciation. Maintenance and repairs are charged to operations as incurred. New tires are capitalized separately from revenue equipment and are reported separately as “Prepaid tires” in the consolidated balance sheets and amortized over two years. Depreciation for financial statement purposes is computed by the straight-line method for all assets other than tractors. We recognize depreciation expense on tractors using the 125% declining balance method. New tractors are depreciated to salvage values of $15,000 while new trailers are depreciated to salvage values of $4,000.

Earnings Per Share, Policy [Policy Text Block]

Earnings per Share

Basic earnings per share is based upon the weighted average common shares outstanding during each year. Diluted earnings per share is based on the basic weighted earnings per share with additional weighted common shares for common stock equivalents.

Income Tax, Policy [Policy Text Block]

Income Taxes

We use the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Such amounts are adjusted, as appropriate, to reflect changes in tax rates expected to be in effect when temporary differences reverse. The effect of a change in tax rates on deferred taxes is recognized in the period that the change is enacted. A valuation allowance is recorded to reduce the Company's deferred tax assets to the amount that is more likely than not to be realized.

Income Tax Uncertainties, Policy [Policy Text Block]

We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. We record interest and penalties related to unrecognized tax benefits in income tax expense.

Subsequent Events, Policy [Policy Text Block]

Subsequent Events

No events occurred requiring disclosure other than the repurchase of an additional 0.2 million shares of our common stock for $4.2 million subsequent to June 30, 2018.