Heartland Express (HTLD) 10-Q 10 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Aug. 07, 2015
Document Information [Line Items]
Entity Registrant Name	HEARTLAND EXPRESS INC
Entity Central Index Key	799,233
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		87,862,138

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
CURRENT ASSETS
Cash and cash equivalents	$ 79,476	$ 17,303
Trade receivables, net	70,460	77,034
Prepaid tires	9,399	10,160
Prepaid shop supplies	1,429	2,056
Other current assets	16,482	8,992
Income tax receivable	2,900	19,920
Deferred income taxes, net	16,536	14,767
Total current assets	196,682	150,232
PROPERTY AND EQUIPMENT
Land and land improvements	24,787	22,463
Buildings	39,548	34,151
Leasehold improvements	6,509	8,033
Furniture and fixtures	2,096	2,096
Shop and service equipment	10,691	10,820
Revenue equipment	583,275	600,335
Construction in progress	341	668
Property, Plant and Equipment, Gross	667,247	678,566
Less accumulated depreciation	208,124	198,007
Property and equipment, net	459,123	480,559
GOODWILL	100,212	100,212
OTHER INTANGIBLES, NET	15,148	16,380
OTHER ASSETS	10,929	12,611
Assets	782,094	759,994
CURRENT LIABILITIES
Accounts payable and accrued liabilities	16,834	8,261
Compensation and benefits	28,262	26,303
Insurance accruals	19,353	19,249
Other accruals	13,475	14,475
Total current liabilities	77,924	68,288
LONG-TERM LIABILITIES
Income taxes payable	15,498	18,296
Long-term debt	0	24,600
Deferred income taxes, net	101,311	101,605
Insurance accruals less current portion	60,998	59,300
Other long-term liabilities	11,653	11,318
Total long-term liabilities	$ 189,460	$ 215,119
COMMITMENTS AND CONTINGENCIES (Note 14)
STOCKHOLDERS' EQUITY
Preferred stock, par value $.01; authorized 5,000 shares; none issued	$ 0	$ 0
Capital stock, common, $.01 par value; authorized 395,000 shares; issued 90,689 in 2015 and 2014; outstanding 87,862 in 2015 and 87,781 in 2014, respectively	907	907
Additional paid-in capital	3,734	4,058
Retained earnings	547,243	509,834
Treasury stock, at cost; 2,827 shares in 2015 and 2,908 in 2014, respectively	(37,174)	(38,212)
Stockholders' Equity Attributable to Parent	514,710	476,587
Liabilities and Stockholders' Equity	$ 782,094	$ 759,994

Consolidated Balance Sheets Con

Consolidated Balance Sheets Consolidated Balance Sheets (Parentheticals) - $ / shares shares in Thousands	Jun. 30, 2015	Dec. 31, 2014
Consolidated Balance Sheets Parentheticals [Abstract]
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	5,000	5,000
Preferred Stock, Shares Issued	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	395,000	395,000
Common Stock, Shares, Issued	90,689	90,689
Common Stock, Shares, Outstanding	87,862	87,781
Treasury Stock, Shares	2,827	2,908

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Operating Revenue	$ 191,684	$ 226,785	$ 379,207	$ 451,265
Operating Expenses
Salaries, wages, and benefits	70,904	71,240	141,900	142,185
Rent and purchased transportation	9,211	13,741	18,537	28,252
Fuel	34,196	59,338	68,452	122,563
Operations and maintenance	8,379	9,776	16,512	19,897
Operating taxes and licenses	4,378	5,319	9,192	10,165
Insurance and claims	3,469	4,370	10,113	11,465
Communications and utilities	1,453	1,553	2,996	3,383
Depreciation and amortization	26,876	26,668	52,850	51,241
Other operating expenses	6,747	7,997	14,505	16,687
Gain on disposal of property and equipment	(9,668)	(13,859)	(19,849)	(15,903)
Total operating expenses	155,945	186,143	315,208	389,935
Operating income	35,739	40,642	63,999	61,330
Interest income	61	106	93	142
Interest expense	0	(132)	(19)	(287)
Income before income taxes	35,800	40,616	64,073	61,185
Federal and state income taxes	12,484	14,144	23,145	20,634
Net income	23,316	26,472	40,928	40,551
Other comprehensive income, net of tax	0	0	0	0
Comprehensive income	$ 23,316	$ 26,472	$ 40,928	$ 40,551
Net income per share
Basic	$ 0.27	$ 0.30	$ 0.47	$ 0.46
Diluted	$ 0.27	$ 0.30	$ 0.47	$ 0.46
Weighted average shares outstanding
Basic	87,814	87,728	87,802	87,716
Diluted	87,967	87,900	87,966	87,908
Dividends declared per share	$ 0.02	$ 0.02	$ 0.04	$ 0.04

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total	Capital Stock, Common	Additional Paid-in Capital	Retained Earnings	Treasury Stock
Balance at Dec. 31, 2014	$ 476,587	$ 907	$ 4,058	$ 509,834	$ (38,212)
Net income	40,928	0	0	40,928	0
Dividends on common stock, $0.04 per share	(3,519)	0	0	3,519	0
Stock-based compensation, net of tax	714	0	(324)	0	1,038
Balance at Jun. 30, 2015	$ 514,710	$ 907	$ 3,734	$ 547,243	$ (37,174)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity Parentheticals - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Dividends declared per share	$ 0.02	$ 0.02	$ 0.04	$ 0.04

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
OPERATING ACTIVITIES
Net income	$ 40,928	$ 40,551
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	53,375	51,779
Deferred income taxes	(2,063)	10,103
Amortization of stock-based compensation, net of tax	(714)	(546)
Gain on disposal of property and equipment	(19,849)	(15,903)
Changes in certain working capital items:
Trade receivables	6,574	(3,758)
Prepaid expenses and other current assets	1,368	(2,237)
Accounts payable, accrued liabilities, and accrued expenses	6,441	(6,979)
Accrued income taxes	14,222	4,046
Net cash provided by operating activities	101,710	78,148
INVESTING ACTIVITIES
Proceeds from sale of property and equipment	57,349	29,432
Purchases of property and equipment, net of trades	(64,703)	(72,384)
Acquisition of business, net of cash acquired	0	(3,011)
Change in designated funds for equipment purchases	(5,741)	0
Change in other assets	1,682	(49)
Net cash used in investing activities	(11,413)	(46,012)
FINANCING ACTIVITIES
Payments of Ordinary Dividends, Common Stock	(1,759)	(1,757)
Contingent consideration related to acquisition	(1,765)	0
Proceeds from Lines of Credit	0	3,000
Repayments on line of credit	(24,600)	(35,000)
Net cash used in financing activities	(28,124)	(33,757)
Net increase (decrease) in cash and cash equivalents	62,173	(1,621)
CASH AND CASH EQUIVALENTS
Beginning of period	17,303	17,763
End of period	79,476	16,142
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest paid	40	306
Cash paid during the period for income taxes, net of refunds	10,802	6,486
Noncash investing and financing activities:
Fair value of revenue equipment traded	0	3,335
Purchased property and equipment in accounts payable	5,682	28,406
Sold property and equipment in other current assets	1,598	0
Common stock dividends declared in accounts payable	$ 1,760	$ 1,759

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2015
Basis of Presentation [Abstract]
Basis of Presentation	Basis of Presentation 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, Gordon Trucking, Inc. (“GTI”), Heartland Express Services, Inc., Heartland Express Maintenance Services, Inc., and A & M Express, Inc. 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. 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. generally accepted accounting principles 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, 2014 included in the Annual Report on Form 10-K of the Company filed with the Securities and Exchange Commission on March 2, 2015. Interim results of operations are not necessarily indicative of the results to be expected for the full year or any other interim periods. There were no changes to the Company's significant accounting policies during the six month period ended June 30, 2015 .

Use of Estimates

Use of Estimates	6 Months Ended
	Jun. 30, 2015
Use of Estimates [Abstract]
Use of Estimates	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. There were no significant changes in estimates and assumptions used by management related to our critical accounting policies during the three and six months ended June 30, 2015 .

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2015
Segment Information [Abstract]
Segment Information	Segment Information We provide multiple transportation services across the United States (U.S.) and parts of Canada. We offer primarily asset-based transportation services in the dry van truckload market and also offer truckload temperature-controlled transportation services and non-asset based brokerage services. None of our transportation services or geographical-based regional terminals individually meet the definition of a segment. Our Chief Operating Decision Maker oversees and manages all of our transportation services and regional terminals, on a combined basis, including the legacy transportation services of 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.

Cash and Cash Equivalents

Cash and Cash Equivalents	6 Months Ended
	Jun. 30, 2015
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents	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. At June 30, 2015 , restricted and designated cash and investments totaled $16.7 million with $5.7 million included in other current assets and $11.0 million included in other non-current assets in the consolidated balance sheet. Restricted and designated cash and investments totaled $12.6 million at December 31, 2014 , all of which was included in other non-current assets in the consolidated balance sheet. The restricted funds represent deposits required by state agencies for self-insurance purposes and designated funds that are earmarked for a specific purpose and not for general business use.

Prepaid Tires, Property, Equipm

Prepaid Tires, Property, Equipment and Depreciation	6 Months Ended
	Jun. 30, 2015
Property, Plant and Depreciation [Abstract]
Property, Equipment, and Depreciation	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. 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 expense of $0.3 million and $0.3 million for the three months ended June 30, 2015 and 2014 and $0.5 million and $0.5 million for the six months ended June 30, 2015 and 2014 , respectively, have been included in communication and utilities in the consolidated statements of comprehensive income. 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 .

Other Intangible, Net and Goodw

Other Intangible, Net and Goodwill	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets and Goodwill	Other Intangibles, Net and Goodwill All intangible assets determined to have finite lives are amortized over their estimated useful lives. The useful life of an intangible asset is the period over which the asset is expected to contribute directly or indirectly to future cash flows. There was no change in the gross amount of identifiable intangible assets during the three and six months ended June 30, 2015 . Amortization expense of $0.6 million , $1.2 million and $0.6 million , $1.2 million for the three and six months ended June 30, 2015 and 2014 , respectively, was included in depreciation and amortization in the consolidated statement of comprehensive income. Intangible assets subject to amortization consisted of the following at June 30, 2015 : Amortization period (years) Gross Amount Accumulated Amortization Net intangible assets (in thousands) Customer relationships 20 $ 7,600 $ 618 $ 6,982 Tradename 6 7,400 2,004 5,396 Covenants not to compete 10 3,100 507 2,593 Real estate options 2.2 942 765 177 $ 19,042 $ 3,894 $ 15,148 Carrying amounts of goodwill were as follows: (in thousands) Balance at December 31, 2014 $ 100,212 Acquisitions — Balance at June 30, 2015 $ 100,212

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Share	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. During the three and six months ended June 30, 2015 and June 30, 2014 , we had outstanding restricted shares of common stock to certain of our employees under the Company's 2011 Restricted Stock Award Plan. A reconciliation of the numerator (net income) and denominator (weighted average number of shares outstanding of the basic and diluted earnings per share ("EPS")) for the three and six months ended June 30, 2015 and June 30, 2014 is as follows (in thousands, except per share data): Three months ended June 30, 2015 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 23,316 87,814 $ 0.27 Effect of restricted stock — 153 Diluted EPS $ 23,316 87,967 $ 0.27 Three months ended June 30, 2014 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 26,472 87,728 $ 0.30 Effect of restricted stock — 172 Diluted EPS $ 26,472 87,900 $ 0.30 Six Months Ended June 30, 2015 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 40,928 87,802 $ 0.47 Effect of restricted stock — 164 Diluted EPS $ 40,928 87,966 $ 0.47 Six Months Ended June 30, 2014 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 40,551 87,716 $ 0.46 Effect of restricted stock — 192 Diluted EPS $ 40,551 87,908 $ 0.46

Equity

Equity	6 Months Ended
	Jun. 30, 2015
Share Repurchases [Abstract]
Stockholders' Equity	Equity In September 2001, our Board of Directors authorized a program to repurchase 15.4 million shares, adjusted for stock splits, of our common stock in open market or negotiated transactions using available cash, cash equivalents and investments which was subsequently amended in February 2012. Approximately 3.2 million shares remain authorized for repurchase under the program as of June 30, 2015 . There were no shares repurchased in the open market during the three and six months ended June 30, 2015 and 2014 . The authorization remains open at June 30, 2015 and has no expiration date. The share repurchase authorization is discretionary and may be suspended or discontinued at any time without prior notice. During the three and six months ended June 30, 2015 and 2014 , our Board of Directors declared regular quarterly dividends totaling $1.8 million , $3.5 million , and $1.8 million , $3.5 million respectively. Future payment of cash dividends and the amount of such dividends will depend upon our financial conditions, our results of operations, our cash requirements, our tax treatment, and certain corporate law requirements, as well as factors deemed relevant by our Board of Directors.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2015
Stock-Based Compensation [Abstract]
Stock Based Compensation	Stock-Based Compensation In July 2011, a Special Meeting of Stockholders of Heartland Express, Inc. was held, at which meeting the approval of the Heartland Express, Inc. 2011 Restricted Stock Award Plan (the “Plan”) was ratified. The Plan is administered by the Compensation Committee of our Board of Directors. Per the terms of the awards, employees receiving awards will have all of the rights of a stockholder with respect to the unvested restricted shares including, but not limited to, the right to receive such cash dividends, if any, as may be declared on such shares from time to time and the right to vote such shares at any meeting of our stockholders. The Plan made available up to 0.9 million shares for the purpose of making restricted stock grants to our eligible officers and employees. As of June 30, 2015 , there were 0.4 million shares that had been granted to employees. The shares granted under the Plan during 2011 are service based awards beginning December 14, 2011 and 20% of the awards vest each June 1st through 2016. There were no shares granted in 2012. The shares granted in 2013 through 2015 are also service based awards and generally vest evenly over two to four years from the date of grant. Once vested, there are no other restrictions on the awards. Compensation expense associated with these awards is based on the market value of our stock on the grant date. Our market closing price on the December 14, 2011 grant date was $13.57 and ranged between $13.86 and $27.47 on the various grant dates for the shares issued in 2013 through June 30, 2015 . There were no significant assumptions made in determining the fair value. Compensation expense associated with restricted stock awards is included in salaries, wages and benefits in the consolidated statements of comprehensive income. Compensation expense associated with restricted stock awards was $0.3 million and $0.6 million and for the three and six months ended June 30, 2015 , respectively. Compensation expense associated with restricted stock awards was $0.3 million and $0.5 million for the three and six months ended June 30, 2014 . Unrecognized compensation expense was $0.9 million at June 30, 2015 which will be recognized over a remaining weighted average period of 1.3 years. The following tables summarizes our restricted stock award activity for the three and six months ended June 30, 2015 and 2014 . Three Months Ended June 30, 2015 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 175.1 $ 16.49 Granted 2.2 21.19 Vested (70.5 ) — Forfeited (2.2 ) — Outstanding (unvested) at end of period 104.6 $ 18.04 Six Months Ended June 30, 2015 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 183.1 $ 16.78 Granted 4.2 24.06 Vested (80.5 ) — Forfeited (2.2 ) — Outstanding (unvested) at end of period 104.6 $ 18.04 Three and Six Months Ended June 30, 2014 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 211.6 $ 13.81 Granted 8.5 22.01 Vested (72.7 ) — Forfeited — — Outstanding (unvested) at end of period 147.4 $ 14.16

Long-Term Debt

Long-Term Debt	6 Months Ended
	Jun. 30, 2015
Line of Credit, Long-Term Debt [Abstract]
Long-Term Debt	Long-Term Debt In November 2013, we entered into a credit agreement (the “Credit Agreement”) by and among Wells Fargo Bank, National Association, (the “Bank”), Heartland Express, Inc. of Iowa as the borrower (the “Borrower”), us, GTI, and the other members of our consolidated group, as Guarantors. Pursuant to the Credit Agreement, the Bank provided a five-year, $250.0 million unsecured revolving line of credit. The line of credit is available for working capital, equipment financing, and general corporate purposes. The Bank's commitment decreased to $225.0 million on November 1, 2014, and will decrease to $200.0 million on November 1, 2015, and to $175.0 million from November 1, 2016 through October 31, 2018. The Credit Agreement is unsecured, with a negative pledge against all assets of our consolidated group, except for debt associated with permitted acquisitions, new purchase-money debt and capital lease obligations as described in the Credit Agreement. The Credit Agreement matures on October 31, 2018. The Borrower has the ability to terminate the commitment at any time at no additional cost to the Borrower. Borrowings under the Credit Agreement can either be, at Borrower's election, (i) one-month or three-month LIBOR (Index) plus 0.625% , floating, or (ii) Prime (Index) plus 0.0% , floating. There is a commitment fee on the unused portion of the Revolver at 0.0625% , due monthly. The Credit Agreement contains customary financial covenants including, but not limited to, (i) a maximum adjusted leverage ratio of 2 :1, measured quarterly on a trailing twelve month basis, (ii) a minimum net income requirement of $1.00 , measured quarterly on a trailing twelve month basis, (iii) a minimum tangible net worth of $200,000,000 requirement, measured quarterly, and (iv) limitations on other indebtedness and liens. The Credit Agreement also includes customary events of default, conditions, representations and warranties, and indemnification provisions. We were in compliance with the respective financial covenants at June 30, 2015 . Long term debt consisted of the following at June 30, 2015 and December 31, 2014 (in thousands): June 30, 2015 December 31, 2014 Long-term debt $ — $ 24,600 The weighted average variable annual percentage rate (“APR”) for amounts borrowed and outstanding at December 31, 2014 was 0.79% . Borrowing under the line of credit is recorded in "Long-term debt" in the consolidated balance sheets. Outstanding letters of credit associated with the revolving line of credit at June 30, 2015 were $4.4 million . As of June 30, 2015 , the line of credit available for future borrowing was $220.6 million .

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	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 statements 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. We had no recorded valuation allowance at June 30, 2015 and December 31, 2014 . Our effective tax rate was 34.9% and 34.8% for the three months ended and 36.1% , and 33.7% for the six months ended June 30, 2015 and 2014 , respectively. The increase in the effective tax rate for 2015 is primarily attributable to a decrease in favorable income tax expense adjustments in 2015 when compared to the same period in 2014 which had a favorable provision to return adjustment that reduced income tax expense. 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. At June 30, 2015 and December 31, 2014 , we had a total of $11.0 million and $12.6 million in gross unrecognized tax benefits, respectively. Of this amount, $7.0 million and $8.0 million represents the amount of unrecognized tax benefits that, if recognized, would impact our effective tax rate as of June 30, 2015 and December 31, 2014 . Unrecognized tax benefits were a net decrease of $1.1 million and $0.8 million during the three months ended June 30, 2015 and 2014 , respectively. Unrecognized tax benefits were a net decrease of $1.6 million and $1.3 million during the six months ended June 30, 2015 and 2014 , respectively. The net decreases during the three month periods of 2015 and 2014 were due mainly to the expiration of certain statutes of limitation net of additions with respective states. This had the effect of decreasing the effective state tax rate during these respective periods. The total net amount of accrued interest and penalties for such unrecognized tax benefits was $4.4 million and $5.7 million at June 30, 2015 and December 31, 2014 and is included in income taxes payable in the consolidated balance sheets. Income tax expense is increased each period for the accrual of interest on outstanding positions and penalties when the uncertain tax position is initially recorded. Income tax expense is reduced in periods by the amount of accrued interest and penalties associated with reversed uncertain tax positions due to lapse of applicable statute of limitations, when applicable or when a position is settled. Net interest and penalties included in income tax expense for the three month period ended June 30, 2015 and 2014 was a benefit of approximately $0.7 million and $0.5 million , respectively. Net interest and penalties included in income tax expense for the six month period ended June 30, 2015 and 2014 was a benefit of approximately $1.2 million and $1.2 million , respectively. Income tax expense was reduced during the three and six months ended June 30, 2015 and 2014 due to reversals of interest and penalties due to lapse of applicable statute of limitations and settlements, net of additions for interest and penalty accruals during the same period. These unrecognized tax benefits relate to risks associated with state income tax filing positions for our corporate subsidiaries. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: 2015 (in thousands) Balance at January 1, 2015 $ 12,632 Additions based on tax positions related to current year 434 Additions for tax positions of prior years — Reductions for tax positions of prior years (90 ) Reductions due to lapse of applicable statute of limitations (1,927 ) Settlements — Balance at June 30, 2015 $ 11,049 A number of years may elapse before an uncertain tax position is audited and ultimately settled. It is difficult to predict the ultimate outcome or the timing of resolution for uncertain tax positions. It is reasonably possible that the amount of unrecognized tax benefits could significantly increase or decrease within the next twelve months. These changes could result from the expiration of the statute of limitations, examinations or other unforeseen circumstances. We do not have any outstanding litigation related to tax matters. At this time, management’s best estimate of the reasonably possible change in the amount of gross unrecognized tax benefits to be a decrease of approximately $1.0 million to a decrease of $2.0 million during the next twelve months mainly due to the expiration of certain statute of limitations, net of additions. The federal statute of limitations remains open for the years 2012 and forward. Tax years 2005 and forward are subject to audit by state tax authorities depending on the tax code and administrative practice of each state.

Operating Leases

Operating Leases	6 Months Ended
	Jun. 30, 2015
Leases [Abstract]
Operating Leases	Operating Leases We have operating leases for certain revenue equipment. During 2015, these leases are all with a commercial tractor dealership, owned by a board member and certain of our employees. During 2014, a portion of our operating leases were with the noted commercial tractor dealership. Rent expense for these leases were $0.8 million and $1.9 million (including related-party rental payments totaling $0.8 million and $1.9 million ) for the three and six months ended June 30, 2015 , respectively. Rent expense for these leases were $2.3 million and $4.6 million (including related-party rental payments totaling $1.8 million , and $3.6 million ), for the three and six months ended 2014 , respectively. These expenses were included in rent and purchased transportation in the consolidated statements of comprehensive income. The various leases expire in 2015 and 2016. We lease certain terminal facilities under operating leases. A portion of these leases are with limited liability companies, whose members include a board member and certain of our employees and a commercial tractor dealership owned by a board member and certain of our employees. Rent expenses for terminal facilities were $1.0 million and $2.1 million (including related-party rental payments totaling $1.0 million and $1.9 million ), for the three and six months ended June 30, 2015 , respectively. Rent expenses for terminal facilities were $1.0 million and $2.1 million (including related-party rental payments totaling $1.0 million and $2.0 million ), for the three and six months ended June 30, 2014 , respectively. These expenses were included in rent and purchased transportation in the consolidated statements of comprehensive income. The various leases expire from 2015 through 2018 and the majority of these facilities contain options to renew. We exercised the purchase option on the Pontoon Beach, IL terminal and finalized this purchase during the second quarter of 2015. We paid $4.9 million to a limited liability company, whose members include a board member and certain of our employees as a result of this transaction. We have a right of first refusal on the sale of the Pacific, Washington location property by the owners. We are responsible for all taxes, insurance, and utilities related to the terminal leases. See Notes 6 and 13 for additional information.

Related Party

Related Party	6 Months Ended
	Jun. 30, 2015
Related Party [Abstract]
Related Party	Related Party We lease terminal facilities for operations under operating leases from certain limited liability companies, whose members include a board member and certain of our employees and a commercial tractor dealership owned by a board member and certain of our employees. The terminal facility leases have initial five year terms, which began November 11, 2013, with options to renew and options to purchase with the exception of the Pacific, Washington location which contains a right of first refusal on any sale of the property. We exercised our option to purchase and ultimately acquired one leased location from a limited liability company referenced above on June 30, 2015. We purchased tractors from and sold tractors to the commercial tractor dealership noted above. We have operating leases for certain revenue equipment with the commercial tractor dealership and we also purchased parts and services from the same commercial tractor dealership. We owed the commercial tractor dealership $1.3 million and $0.1 million , included in accounts payable and accrued liabilities in the consolidated balance sheets at June 30, 2015 and December 31, 2014 , respectively, for tractors delivered but not paid for prior to these dates and outstanding parts and services. The commercial tractor dealership owed us $0.5 million and $0.0 million , included in other current assets in the consolidated balance sheets at June 30, 2015 and December 31, 2014 , respectively, for tractors traded but not paid for prior to those dates. The related payments (receipts) with related parties for the three and six months ended June 30, 2015 and 2014 (in thousands) were as follows: Three months ended June 30, 2015 2014 Payments for tractor purchases $ 22,795 $ 505 Receipts for tractor sales (11,041 ) (1,299 ) Revenue equipment lease payments 799 1,817 Payments for parts and services 1,065 1,364 Terminal lease payments 963 977 Terminal lease purchase option payment 4,875 2,825 Administrative services receipts — (141 ) $ 19,456 $ 6,048 Six months ended June 30, 2015 2014 Payments for tractor purchases $ 24,895 $ 11,988 Receipts for tractor sales (19,567 ) (4,497 ) Revenue equipment lease payments 1,884 3,646 Payments for parts and services 2,426 2,906 Terminal lease payments 1,919 2,005 Terminal lease purchase option payment 4,875 2,825 Administrative services receipts — (282 ) $ 16,432 $ 18,591

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies We are a party to ordinary, routine litigation and administrative proceedings incidental to its business. In the opinion of management, our potential exposure under pending legal proceedings is adequately provided for in the accompanying consolidated financial statements. The total estimated purchase commitments for tractors, net of tractor sale commitments, and trailer equipment, to be delivered through the remainder of 2015 was $58.3 million at June 30, 2015 . We have a purchase commitment with a related party of $11.6 million $12.0 million related to our exercise of a purchase option on the Rancho Cucamonga, CA terminal expected to be finalized by September 30, 2015.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events We have evaluated events occurring subsequent to June 30, 2015 through the filing date of this Quarterly Report on Form 10-Q for disclosure. No events occurred requiring disclosure.

Basis of Presentation Basis of

Basis of Presentation Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2015
Basis of Presentation [Abstract]
Basis of Presentation [Policy Text Block]	Basis of Presentation 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, Gordon Trucking, Inc. (“GTI”), Heartland Express Services, Inc., Heartland Express Maintenance Services, Inc., and A & M Express, Inc. 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. 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. generally accepted accounting principles 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, 2014 included in the Annual Report on Form 10-K of the Company filed with the Securities and Exchange Commission on March 2, 2015. Interim results of operations are not necessarily indicative of the results to be expected for the full year or any other interim periods.
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 multiple transportation services across the United States (U.S.) and parts of Canada. We offer primarily asset-based transportation services in the dry van truckload market and also offer truckload temperature-controlled transportation services and non-asset based brokerage services. None of our transportation services or geographical-based regional terminals individually meet the definition of a segment. Our Chief Operating Decision Maker oversees and manages all of our transportation services and regional terminals, on a combined basis, including the legacy transportation services of 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.
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]	Property and equipment are reported at cost, net of accumulated depreciation. Maintenance and repairs are charged to operations as incurred. 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 statements 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 We have evaluated events occurring subsequent to June 30, 2015 through the filing date of this Quarterly Report on Form 10-Q for disclosure.

Other Intangible, Net and Goo24

Other Intangible, Net and Goodwill (Tables)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets [Table Text Block]	Amortization period (years) Gross Amount Accumulated Amortization Net intangible assets (in thousands) Customer relationships 20 $ 7,600 $ 618 $ 6,982 Tradename 6 7,400 2,004 5,396 Covenants not to compete 10 3,100 507 2,593 Real estate options 2.2 942 765 177 $ 19,042 $ 3,894 $ 15,148
Schedule of Goodwill [Table Text Block]	Carrying amounts of goodwill were as follows: (in thousands) Balance at December 31, 2014 $ 100,212 Acquisitions — Balance at June 30, 2015 $ 100,212

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	Three months ended June 30, 2015 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 23,316 87,814 $ 0.27 Effect of restricted stock — 153 Diluted EPS $ 23,316 87,967 $ 0.27 Three months ended June 30, 2014 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 26,472 87,728 $ 0.30 Effect of restricted stock — 172 Diluted EPS $ 26,472 87,900 $ 0.30 Six Months Ended June 30, 2015 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 40,928 87,802 $ 0.47 Effect of restricted stock — 164 Diluted EPS $ 40,928 87,966 $ 0.47 Six Months Ended June 30, 2014 Net Income (numerator) Shares (denominator) Per Share Amount Basic EPS $ 40,551 87,716 $ 0.46 Effect of restricted stock — 192 Diluted EPS $ 40,551 87,908 $ 0.46

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2015
Stock-Based Compensation [Abstract]
Disclosure of restricted stock award activity	The following tables summarizes our restricted stock award activity for the three and six months ended June 30, 2015 and 2014 . Three Months Ended June 30, 2015 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 175.1 $ 16.49 Granted 2.2 21.19 Vested (70.5 ) — Forfeited (2.2 ) — Outstanding (unvested) at end of period 104.6 $ 18.04 Six Months Ended June 30, 2015 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 183.1 $ 16.78 Granted 4.2 24.06 Vested (80.5 ) — Forfeited (2.2 ) — Outstanding (unvested) at end of period 104.6 $ 18.04 Three and Six Months Ended June 30, 2014 Number of Shares of Restricted Stock Awards (in thousands) Weighted Average Grant Date Fair Value Unvested at beginning of period 211.6 $ 13.81 Granted 8.5 22.01 Vested (72.7 ) — Forfeited — — Outstanding (unvested) at end of period 147.4 $ 14.16

Long-Term Debt (Tables)

Long-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2015
Line of Credit, Long-Term Debt [Abstract]
Schedule of Long-term Debt	Long term debt consisted of the following at June 30, 2015 and December 31, 2014 (in thousands): June 30, 2015 December 31, 2014 Long-term debt $ — $ 24,600

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Reconciliation of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: 2015 (in thousands) Balance at January 1, 2015 $ 12,632 Additions based on tax positions related to current year 434 Additions for tax positions of prior years — Reductions for tax positions of prior years (90 ) Reductions due to lapse of applicable statute of limitations (1,927 ) Settlements — Balance at June 30, 2015 $ 11,049

Related Party (Tables)

Related Party (Tables)	6 Months Ended
	Jun. 30, 2015
Related Party [Abstract]
Schedule of Related Party Transactions [Table Text Block]	The related payments (receipts) with related parties for the three and six months ended June 30, 2015 and 2014 (in thousands) were as follows: Three months ended June 30, 2015 2014 Payments for tractor purchases $ 22,795 $ 505 Receipts for tractor sales (11,041 ) (1,299 ) Revenue equipment lease payments 799 1,817 Payments for parts and services 1,065 1,364 Terminal lease payments 963 977 Terminal lease purchase option payment 4,875 2,825 Administrative services receipts — (141 ) $ 19,456 $ 6,048 Six months ended June 30, 2015 2014 Payments for tractor purchases $ 24,895 $ 11,988 Receipts for tractor sales (19,567 ) (4,497 ) Revenue equipment lease payments 1,884 3,646 Payments for parts and services 2,426 2,906 Terminal lease payments 1,919 2,005 Terminal lease purchase option payment 4,875 2,825 Administrative services receipts — (282 ) $ 16,432 $ 18,591

Segment Information (Details)

Segment Information (Details)	6 Months Ended
	Jun. 30, 2015segments
Segment Information [Abstract]
Number of Segments	1

Cash and Cash Equivalents (Deta

Cash and Cash Equivalents (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Restricted Cash and Cash Equivalents	$ 16.7	$ 12.6
Restricted Cash and Investments, Current	5.7	0
Restricted Cash and Cash Equivalents, Noncurrent	$ 11	$ 12.6

Prepaid Tires, Property, Equi32

Prepaid Tires, Property, Equipment and Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Property, Plant and Equipment [Line Items]
Amortization Period of Tires			2 years
Tractors
Property, Plant and Equipment [Line Items]
Property, Plant, and Equipment, Salvage Value	$ 15		$ 15
Trailers
Property, Plant and Equipment [Line Items]
Property, Plant, and Equipment, Salvage Value	4		4
Communications and Utilities Expense
Property, Plant and Equipment [Line Items]
Depreciation	$ 300	$ 300	$ 500	$ 500

Other Intangible, Net and Goo33

Other Intangible, Net and Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Change In Gross Amount of Identifiable Intangible Assets			$ 0
Finite-Lived Intangible Assets, Amortization Expense	$ 607	$ 591	1,214	$ 1,182
Finite-Lived Intangible Assets [Line Items]
Gross Amount	19,042		19,042
Accumulated Amortization	3,894		3,894
Net Intangible Assets	15,148		$ 15,148
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amortization period (years)			20 years
Gross Amount	7,600		$ 7,600
Accumulated Amortization	618		618
Net Intangible Assets	6,982		$ 6,982
Tradename
Finite-Lived Intangible Assets [Line Items]
Amortization period (years)			6 years
Gross Amount	7,400		$ 7,400
Accumulated Amortization	2,004		2,004
Net Intangible Assets	5,396		$ 5,396
Covenants Not to Compete
Finite-Lived Intangible Assets [Line Items]
Amortization period (years)			10 years
Gross Amount	3,100		$ 3,100
Accumulated Amortization	507		507
Net Intangible Assets	2,593		$ 2,593
Real Estate Options
Finite-Lived Intangible Assets [Line Items]
Amortization period (years)			2 years 2 months 12 days
Gross Amount	942		$ 942
Accumulated Amortization	765		765
Net Intangible Assets	$ 177		$ 177

Other Intangible, Net and Goo34

Other Intangible, Net and Goodwill Changes carrying amount of goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2015USD ($)
Intangible Assets and Goodwill [Abstract]
Goodwill, Beginning balance	$ 100,212
Acquisitions	0
Goodwill, Ending Balance	$ 100,212

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Net income	$ 23,316	$ 26,472	$ 40,928	$ 40,551
Basic EPS, Shares	87,814	87,728	87,802	87,716
Basic EPS, Per Share Amount	$ 0.27	$ 0.30	$ 0.47	$ 0.46
Effect of restricted stock	$ 0	$ 0	$ 0	$ 0
Effect of restricted stock, Shares	153	172	164	192
Diluted EPS, Net Income	$ 23,316	$ 26,472	$ 40,928	$ 40,551
Diluted EPS, Shares	87,967	87,900	87,966	87,908
Diluted EPS, Per Share Amount	$ 0.27	$ 0.30	$ 0.47	$ 0.46

Equity (Details)

Equity (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2001
Share Repurchases [Abstract]
Stock Repurchase Shares Authorized					15,400
Number of Shares Authorized to be Repurchased	3,225		3,225
Treasury Stock, Shares, Acquired	0		0	0
Dividends, Common Stock, Cash	$ 1.8	$ 1.8	$ 3.5	$ 3.5

Equity Dividends Paid (Details)

Equity Dividends Paid (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Stockholders' Equity Attributable to Parent [Abstract]
Dividends, Common Stock, Cash	$ 1.8	$ 1.8	$ 3.5	$ 3.5

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		40 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Mar. 31, 2015	Jun. 30, 2015	Dec. 14, 2011	Jul. 11, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual Vesting Percentage			20.00%
Weighted Average Exercise Price of Stock Awards	$ 16.49	$ 14.16	$ 16.78	$ 13.81	$ 16.49	$ 18.04	$ 13.57
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					1 year 3 months
Restricted Stock Shares Authorized								900,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			430,000
Stock-based Compensation	$ 292	$ 285	$ 575	$ 546
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized						$ 900
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested at beginning of year, Number of Restricted Stock Awards (in shares)	175,100		183,100	211,600
Unvested at beginning of year, Weighted Average Grant Date Fair Value (in dollars)	$ 16.49		$ 16.78	$ 13.81
Share-based Compensation Arrangements by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	2,200		4,200	8,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 21.19		$ 24.06	$ 22
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(70,500)		(80,500)	(72,700)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value			$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	2,200		2,200	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0		$ 0	$ 0
Outstanding (unvested) at end of year, Number of Restricted Stock Awards (in shares)	104,600	147,400	104,600	147,400	175,100
Outstanding (unvested) at end of year, Weighted Average Grant Date Fair Value (in dollars)	$ 18.04	$ 14.16	$ 18.04	$ 14.16	$ 16.49
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value price of stock awards lower			13.86
weighted average fair value price of stock awards upper			$ 27.47

Long-Term Debt (Details)

Long-Term Debt (Details)	6 Months Ended
	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)	Nov. 01, 2014USD ($)	Dec. 31, 2013USD ($)
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate		0.00%
Line of Credit Facility, Maximum Borrowing Capacity, Current			$ 225,000,000	$ 250,000,000
Line of Credit Facility, Maximum Borrowing Capacity, Period 2	$ 200,000,000
Line of Credit Facility, Maximum Borrowing Capacity, Period 3	$ 175,000,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.0625%
Debt Instrument, Covenant, Leverage Ratio	2
Debt Covenant, Minimum Net Income Requirement	$ 1
Debt Instrument, Minimum Tangible Net Worth	200,000,000
Long-term Debt	0	$ 24,600,000
letters of credit outstanding on a line of credit	4,400,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 220,600,000
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.625%
Prime Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.00%

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Effective Income Tax Rate, Percent	34.90%	34.80%	36.10%	33.70%
Valuation Allowance [Abstract]
Valuation Allowance, Amount	$ 0		$ 0		$ 0
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	7,000		7,000		8,000
Unrecognized Tax Benefits, Period Increase (Decrease)	(1,100)	$ (800)	(1,600)	$ (1,300)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	4,400		4,400		$ 5,700
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	(709)	$ (500)	(1,215)	$ (1,208)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance beginning of period			12,632
Additions based on tax positions related to current year			434
Additions for tax positions of prior years			0
Reductions for tax positions of prior years			(90)
Reductions due to lapse of applicable statute of limitations			(1,927)
Settlements			0
Balance end of period	11,049		11,049
Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	(2,000)		(2,000)
Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	$ (1,000)		$ (1,000)

Operating Leases (Details)

Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	$ 800	$ 2,300	$ 1,900	$ 4,600
related party payment for terminal purchase	4,875	2,825	4,875	2,825
Related Party
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	799	1,817	1,884	3,646
Terminal Facilities
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	1,000	1,000	2,100	2,100
Terminal Facilities | Related Party
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	$ 963	$ 977	$ 1,900	$ 2,000

Related Party (Details)

Related Party (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Due to Related Parties, Current	$ 1,300		$ 1,300		$ 100
Receipts for tractor sales			0	$ 3,335
Operating Leases, Rent Expense	800	$ 2,300	1,900	4,600
related party payment for terminal purchase	4,875	2,825	4,875	2,825
Due from Related Parties, Current	500		500		$ 0
Costs and Expenses, Related Party	19,456	6,048	16,432	18,591
Related Party
Related Party Transaction [Line Items]
Payments for tractor purchase	22,795	505	24,895	11,988
Receipts for tractor sales	(11,041)	(1,299)	(19,567)	(4,497)
Operating Leases, Rent Expense	799	1,817	1,884	3,646
Payments for parts and services	1,065	1,364	2,426	2,906
Administrative Services Revenue	0	(141)	0	(282)
Terminal Facilities
Related Party Transaction [Line Items]
Operating Leases, Rent Expense	1,000	1,000	2,100	2,100
Terminal Facilities | Related Party
Related Party Transaction [Line Items]
Operating Leases, Rent Expense	$ 963	$ 977	$ 1,900	$ 2,000

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	Aug. 07, 2015	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Unrecorded Unconditional Purchase Obligation		$ 58.3
related party terminal purchase commitment	$ 11.6