Knight-Swift Transportation (KNX) 10-K 17 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Feb. 06, 2017	Jun. 30, 2016
Entity Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	SWFT
Entity Registrant Name	SWIFT TRANSPORTATION Co
Entity Central Index Key	1,492,691
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,248,343,682
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Class A Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		83,322,456
Class B Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		49,741,938

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents		$ 89,391	$ 107,590
Cash and cash equivalents — restricted		57,046	55,241
Restricted investments, held to maturity, amortized cost	[1]	22,717	23,215
Accounts receivable, net		408,593	422,421
Income tax refund receivable		206	11,664
Inventories and supplies		16,630	18,426
Assets held for sale		6,969	9,084
Prepaid taxes, licenses, insurance, and other		47,038	48,149
Current portion of notes receivable		6,961	9,817
Total current assets		655,551	705,607
Property and equipment, at cost:
Revenue and service equipment		2,266,137	2,278,618
Land		132,084	131,693
Facilities and improvements		281,390	269,769
Furniture and office equipment		113,880	99,519
Total property and equipment		2,793,491	2,779,599
Less: accumulated depreciation and amortization		(1,244,890)	(1,128,499)
Net property and equipment		1,548,601	1,651,100
Other assets		21,953	26,585
Intangible assets, net		266,305	283,119
Goodwill		253,256	253,256
Total assets		2,745,666	2,919,667
Current liabilities:
Accounts payable		115,063	121,827
Accrued liabilities		132,712	97,313
Current portion of claims accruals		80,866	84,429
Current portion of long-term debt		8,459	35,514
Current portion of capital lease obligations		72,473	59,794
Total current liabilities		409,573	398,877
Revolving line of credit	[2]	130,000	200,000
Long-term debt, less current portion		493,346	643,663
Capital lease obligations, less current portion		161,463	222,001
Claims accruals, less current portion		165,726	149,281
Deferred income taxes		427,722	463,832
Accounts receivable securitization		279,285	223,927
Other liabilities		6,296	959
Total liabilities		2,073,411	2,302,540
Commitments and contingencies (notes 15, 16, and 17)
Stockholders’ equity:
Preferred stock		0	0
Class A common stock		833	878
Class B common stock		497	510
Additional paid-in capital		701,065	754,589
Accumulated deficit		(30,242)	(139,033)
Accumulated other comprehensive income		0	81
Noncontrolling interest		102	102
Total stockholders’ equity		672,255	617,127
Total liabilities and stockholders’ equity		$ 2,745,666	$ 2,919,667
[1]	Restricted investments are included in "Restricted investments, held to maturity, amortized cost."
[2]	The Company also had outstanding letters of credit under the New Revolver, primarily related to workers' compensation and self-insurance liabilities of $97.0 million at December 31, 2016 and $95.0 million at December 31, 2015.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Class A Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	83,299,118	87,808,801
Common stock, shares outstanding	83,299,118	87,808,801
Class B Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	49,741,938	50,991,938
Common stock, shares outstanding	49,741,938	50,991,938

Consolidated Income Statements

Consolidated Income Statements - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating revenue:
Revenue, excluding fuel surcharge revenue	$ 3,722,863,000	$ 3,781,976,000	$ 3,535,391,000
Fuel surcharge revenue	308,654,000	447,346,000	763,333,000
Operating revenue	4,031,517,000	4,229,322,000	4,298,724,000
Operating expenses:
Salaries, wages, and employee benefits	1,148,610,000	1,111,946,000	970,683,000
Operating supplies and expenses	389,968,000	387,735,000	342,073,000
Fuel	345,281,000	416,782,000	591,855,000
Purchased transportation	1,116,709,000	1,180,403,000	1,321,268,000
Rental expense	226,258,000	240,501,000	229,290,000
Insurance and claims	192,733,000	179,545,000	159,246,000
Depreciation and amortization of property and equipment	267,134,000	251,735,000	221,122,000
Amortization of intangibles	16,814,000	16,814,000	16,814,000
Impairments	807,000	0	2,308,000
Gain on disposal of property and equipment	(18,285,000)	(32,453,000)	(27,682,000)
Communication and utilities	28,723,000	31,606,000	29,871,000
Operating taxes and licenses	74,753,000	74,604,000	71,806,000
Total operating expenses	3,789,505,000	3,859,218,000	3,928,654,000
Operating income	242,012,000	370,104,000	370,070,000
Other expenses (income):
Interest expense	30,598,000	38,350,000	80,064,000
Derivative interest expense	0	3,972,000	6,495,000
Interest income	(2,634,000)	(2,526,000)	(2,909,000)
Loss on debt extinguishment	0	9,567,000	39,909,000
Non-cash impairments of non-operating assets	0	1,480,000	0
Loss on sale of real property	0	133,000	0
Legal settlements and reserves	3,000,000	6,000,000	0
Other income, net	(3,921,000)	(3,658,000)	(4,115,000)
Total other expenses (income), net	27,043,000	53,318,000	119,444,000
Income before income taxes	214,969,000	316,786,000	250,626,000
Income tax expense	65,702,000	119,209,000	89,474,000
Net income	$ 149,267,000	$ 197,577,000	$ 161,152,000
Basic earnings per share	$ 1.11	$ 1.39	$ 1.14
Diluted earnings per share	$ 1.10	$ 1.38	$ 1.12
Shares used in per share calculations
Basic	134,139	142,018	141,431
Diluted	135,494	143,668	143,475

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 149,267	$ 197,577	$ 161,152
Accumulated losses on derivatives reclassified to derivative interest expense	0	3,886	6,218
Other	(81)	0	0
Other comprehensive (loss) income before income taxes	(81)	3,886	6,218
Income tax effect of items within other comprehensive (loss) income	0	(1,469)	(2,392)
Other comprehensive (loss) income, net of income taxes	(81)	2,417	3,826
Total comprehensive income	$ 149,186	$ 199,994	$ 164,978

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($)	Total	Common Stock [Member]	Common Stock [Member]Class A Common Stock [Member]	Common Stock [Member]Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2013	$ 283,587,000		$ 883,000	$ 525,000	$ 759,408,000	$ (471,169,000)	$ (6,162,000)	$ 102,000
Beginning balance, shares at Dec. 31, 2013			88,402,991	52,441,938
Exercise of stock options	$ 11,488,000		$ 11,000		11,477,000
Exercise of stock options, shares	1,100,998		1,100,998
Stock-based compensation expense	$ 5,080,000				5,080,000
Excess tax benefit from stock-based compensation	3,730,000				3,730,000
Grant of restricted Class A common stock	315,000		$ 1,000		314,000
Grant of restricted Class A common stock, shares			98,866
Shares issued under employee stock purchase plan	1,116,000		$ 1,000		1,115,000
Shares issued under employee stock purchase plan, shares			50,788
Repurchase and cancellation of Class A common stock	$ 0
Repurchase and cancellation of Class A common stock, shares	0
Conversion of Class B common stock to Class A common stock	$ 0		$ 15,000	$ (15,000)
Conversion of Class B common stock to Class A common stock, shares			1,450,000	(1,450,000)
Net income	161,152,000					161,152,000
Other comprehensive income, net of income taxes	3,826,000						3,826,000
Ending balance at Dec. 31, 2014	470,294,000		$ 911,000	$ 510,000	781,124,000	(310,017,000)	(2,336,000)	102,000
Ending balance, shares at Dec. 31, 2014			91,103,643	50,991,938
Exercise of stock options	$ 6,953,000		$ 8,000		6,945,000
Exercise of stock options, shares	665,531		821,412
Stock-based compensation expense	$ 6,525,000				6,525,000
Excess tax benefit from stock-based compensation	2,147,000				2,147,000
Shares issued under employee stock purchase plan	1,214,000		$ 1,000		1,213,000
Shares issued under employee stock purchase plan, shares			59,556
Repurchase and cancellation of Class A common stock	$ (70,000,000)		$ (42,000)		(43,365,000)	(26,593,000)
Repurchase and cancellation of Class A common stock, shares	(4,176,000)		(4,175,810)
Conversion of Class B common stock to Class A common stock, shares		0
Net income	$ 197,577,000					197,577,000
Other comprehensive income, net of income taxes	2,417,000						2,417,000
Ending balance at Dec. 31, 2015	617,127,000		$ 878,000	$ 510,000	754,589,000	(139,033,000)	81,000	102,000
Ending balance, shares at Dec. 31, 2015			87,808,801	50,991,938
Common stock issued under stock plans	$ 13,237,000		$ 15,000		13,222,000
Common stock issued under stock plans, shares			1,546,132
Exercise of stock options, shares	1,253,152
Stock-based compensation expense	$ 6,017,000				6,017,000
Excess tax benefit from stock-based compensation	2,575,000				2,575,000
Shares issued under employee stock purchase plan	1,232,000		$ 1,000		1,231,000
Shares issued under employee stock purchase plan, shares			77,462
Repurchase and cancellation of Class A common stock	$ (117,119,000)		$ (74,000)		(76,569,000)	(40,476,000)
Repurchase and cancellation of Class A common stock, shares	(7,383,000)		(7,383,277)
Conversion of Class B common stock to Class A common stock	$ 0		$ 13,000	$ (13,000)
Conversion of Class B common stock to Class A common stock, shares			1,250,000	(1,250,000)
Net income	149,267,000					149,267,000
Other comprehensive income, net of income taxes	(81,000)						(81,000)
Ending balance at Dec. 31, 2016	$ 672,255,000		$ 833,000	$ 497,000	$ 701,065,000	$ (30,242,000)	$ 0	$ 102,000
Ending balance, shares at Dec. 31, 2016			83,299,118	49,741,938

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 149,267	$ 197,577	$ 161,152
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment, and intangibles	283,948	268,549	237,936
Amortization of debt issuance costs, original issue discount, and other	1,333	5,937	10,407
Gain on disposal of property and equipment, less write-off of totaled tractors	(15,854)	(30,195)	(23,236)
Gain on sale of real property	0	0	(3,018)
Impairments	807	1,480	2,308
Deferred income taxes	(36,079)	26,476	(3,980)
Provision (Reduction)	(1,147)	8,004	2,844
Non-cash loss on debt extinguishment and write-offs of deferred financing costs and original issue discount	0	9,567	11,994
Stock-based compensation expense	6,017	6,525	5,396
Excess tax benefit from stock-based compensation	(2,575)	(2,147)	(3,730)
Income effect of mark-to-market adjustment of interest rate swaps	0	87	(155)
Increase (decrease) in cash resulting from changes in:
Accounts receivable	14,975	48,574	(63,407)
Inventories and supplies	1,796	566	(562)
Prepaid expenses and other current assets	20,999	17,741	17,802
Other assets	1,171	7,785	14,745
Accounts payable, and accrued and other liabilities	41,654	2,972	29,285
Net cash provided by operating activities	466,312	569,498	395,781
Cash flows from investing activities:
(Increase) decrease in cash and cash equivalents — restricted	(1,805)	(9,620)	5,212
Proceeds from maturities of investments	30,269	33,015	29,783
Purchases of investments	(30,061)	(31,930)	(28,921)
Proceeds from sale of property and equipment	113,410	116,330	133,020
Capital expenditures	(239,446)	(342,615)	(305,966)
Payments received on notes receivable	10,114	4,252	5,481
Expenditures on assets held for sale	(31,027)	(25,937)	(4,053)
Payments received on assets held for sale	25,939	14,410	25,326
Payments received on equipment sale receivables	0	288	368
Net cash used in investing activities	(122,607)	(241,807)	(139,750)
Cash flows from financing activities:
Repayment of long-term debt and capital leases	(246,829)	(979,816)	(1,224,628)
Proceeds from long-term debt	0	684,504	900,000
Net (repayments) borrowings on revolving line of credit	(70,000)	143,000	40,000
Borrowings under accounts receivable securitization	105,000	75,000	119,000
Repayment of accounts receivable securitization	(50,000)	(184,000)	(49,000)
Payment of deferred loan costs	0	(4,235)	(11,783)
Proceeds from common stock issued	14,469	8,167	12,604
Repurchase of Class A common stock	(117,119)	(70,000)	0
Excess tax benefits from stock-based compensation	2,575	2,147	3,730
Net cash used in financing activities	(361,904)	(325,233)	(210,077)
Net (decrease) increase in cash and cash equivalents	(18,199)	2,458	45,954
Cash and cash equivalents at beginning of period	107,590	105,132	59,178
Cash and cash equivalents at end of period	89,391	107,590	105,132
Cash paid during the period for:
Interest	29,150	45,390	89,341
Income taxes	79,250	78,522	82,776
Non-cash investing activities:
Equipment purchase accrual	11,103	447	35,831
Notes receivable from sale of assets	4,158	7,670	5,431
Equipment sales receivables	0	0	288
Non-cash financing activities:
Capital lease additions	12,811	145,338	101,581
Accrued deferred loan costs	0	105	177
Insurance premium notes payable	$ 8,430	$ 7,658	$ 37

Introduction and Basis of Prese

Introduction and Basis of Presentation	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation [Text Block]	Introduction and Basis of Presentation Certain acronyms and terms used throughout this Annual Report on Form 10-K are specific to our company, commonly used in our industry, or are otherwise frequently used throughout our document. Definitions for these acronyms and terms are provided in the "Glossary of Terms," available in the front of this document. Description of Business Swift is a transportation solutions provider, headquartered in Phoenix, Arizona. As of December 31, 2016 , the Company's fleet of revenue equipment included 18,366 tractors (comprised of 13,937 company tractors and 4,429 owner-operator tractors), 64,066 trailers and 9,131 intermodal containers. The Company's four reportable segments are Truckload, Dedicated, Swift Refrigerated, and Intermodal. Basis of Presentation The accompanying consolidated financial statements include the accounts of Swift Transportation Company and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in preparing the consolidated financial statements. When the Company does not have a controlling interest in an entity, but exerts significant influence over the entity, the Company applies the equity method of accounting. In management's opinion, the accompanying financial statements were prepared in accordance with principles generally accepted in the United States and include all adjustments necessary for the fair presentation of the periods presented. Change in Accounting Estimate In August 2016, the Company decreased the estimated residual values of a certain group of its tractors, as a result of recent trends in the used tractor market. Management prospectively accounted for this as a change in accounting estimate. This change increased "Depreciation and amortization of property and equipment" in the consolidated income statements by approximately $9.0 million for the year ended December 31, 2016 . Without this change in estimate, basic and diluted earnings per share would have been $0.05 higher for the year ended December 31, 2016. In October 2016, the Company changed its estimated residual values on certain trailers. This accelerated the depreciation on some trailers, while decelerating the depreciation on others. Management prospectively accounted for this as a change in accounting estimate. The impact on "Depreciation and amortization of property and equipment" was a decrease of approximately $0.6 million . Without this change in estimate, basic and diluted earnings per share would have been unaffected for the year ended December 31, 2016. Changes in Presentation Beginning in 2016, the Company made the following changes in presentation: In April 2015, FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs , which amended ASC Subtopic 835-30, Interest – Imputation of Interest. The amendments in this ASU simplify the presentation of debt issuance costs and align the presentation with debt discounts. Entities are required to present debt issuance costs within liabilities as a direct deduction from the face amount of the related debt, rather than as a deferred charge within assets. In August 2015, FASB issued ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements – Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting (SEC Update) , which also amended ASC Subtopic 835-30, Interest – Imputation of Interest . The SEC determined that ASU 2015-03 (discussed above) did not address costs related to line-of-credit arrangements. The amendments in ASU 2015-15 clarify that entities may defer and present debt issuance costs as an asset, and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The amendments in these ASUs require retrospective application, with related disclosures for a change in accounting principle. For public business entities, the amendments in these ASUs were effective for financial statements issued for fiscal years beginning after December 15, 2015, and the interim periods within those fiscal years, with early adoption permitted. The Company adopted this guidance at the beginning of 2016. Accordingly, DLCs, except for those associated with the Company's New Revolver, are presented as direct deductions from the face amount of the related debt. The Company retrospectively adjusted the December 31, 2015 consolidated balance sheet to align with the current period presentation, as follows: December 31, 2015 Financial Statement Caption Unadjusted Consolidated Balance Sheet Reclassification Adjustments Adjusted Consolidated Balance Sheet (In thousands) ASSETS: Other assets $ 29,353 $ (2,768 ) $ 26,585 LIABILITIES: Current portion of long-term debt $ 35,582 $ (68 ) $ 35,514 Long-term debt, less current portion 645,290 (1,627 ) 643,663 Accounts receivable securitization 225,000 (1,073 ) 223,927 Beginning in 2015, the Company made the following changes in presentation: • Excess tax benefits from stock-based compensation are separately presented within "Net cash provided by operating activities" in the consolidated statements of cash flows. The prior period presentation has been retrospectively adjusted to reclassify the amount out of "Accounts payable, accrued and other liabilities" and into the new line item "Excess tax benefits from stock-based compensation." The change in presentation has no net impact on "Net cash provided by operating activities." • Gross amounts of investment in securities activities are presented as "Proceeds from maturities of investments" and "Purchases of investments" in the consolidated statements of cash flows. The prior period presentation has been retrospectively adjusted to accommodate this gross presentation. The change in presentation has no net impact on "Net cash used in investing activities." • "Operating revenue" in the consolidated income statements is disaggregated into the line items "Revenue, excluding fuel surcharge revenue" and "Fuel surcharge revenue." The change in presentation has no net impact on "Operating revenue."

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies [Text Block]	Summary of Significant Accounting Policies Use of Estimates — The preparation of the consolidated financial statements, in accordance with US-GAAP, requires management to make estimates and assumptions about future events that affect the amounts reported in the Company's consolidated financial statements and accompanying notes. On an ongoing basis, management evaluates and periodically adjusts its estimates and assumptions, based on historical experience, the impact of the current economic environment, and other key factors. Volatile energy markets, as well as changes in consumer spending have increased the inherent uncertainty in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Significant items subject to such estimates and assumptions include: • carrying amount of property and equipment, intangibles, and goodwill; • valuation allowances for receivables, inventories, and deferred income tax assets; • valuation of financial instruments; • calculation of stock-based compensation; • estimates of claims accruals; • leases, and • contingent obligations. Segments — The Company uses the "management approach" to determine its reportable segments, as well as to determine the basis of reporting the operating segment information. The management approach focuses on financial information that management uses to make operating decisions. Our CODMs use operating revenues, operating expense categories, operating ratios, operating income, and key operating statistics to evaluate performance and allocate resources to the Company's operations. Operating income is the measure that management uses to evaluate segment performance and allocate resources, which is consistent with US-GAAP for segment reporting. Operating income should not be viewed as a substitute for US-GAAP net income (loss). Management believes the presentation of operating income enhances the understanding of the Company's performance by highlighting the results of operations and the underlying profitability drivers of the business segments. Operating income is defined as operating revenues less operating expenses, before income tax expense. Based on the unique nature of the Company's operating structure, revenue-generating assets are interchangeable between segments. Therefore, the Company does not prepare separate balance sheets by segment, as assets are not separately identifiable by segment. The Company allocates depreciation and amortization expense of its property and equipment to the segments based on the actual utilization of the asset by the segment during the period. Cash and Cash Equivalents — The Company considers all highly liquid debt instruments purchased with original maturities of three months or less to be cash equivalents. Restricted Cash — The Company's wholly-owned captive insurance companies, Red Rock and Mohave, maintain certain operating bank accounts, working trust accounts, and investment accounts. The cash and short-term investments within the accounts are restricted by insurance regulations to fund the insurance claim losses to be paid by the captive insurance companies. Therefore, these cash and short-term investments are classified as "Cash and cash equivalents – restricted" in the consolidated balance sheets. Restricted Investments — The Company's investments are restricted by insurance regulations to fund the insurance claim losses to be paid by the captive insurance companies. The Company accounts for its investments in accordance with ASC Topic 320, Investments – Debt and Equity Securities . Management determines the appropriate classification of its investments in debt securities at the time of purchase and re-evaluates the determination on a quarterly basis. As of December 31, 2016 , all of the Company's investments in fixed-maturity securities were classified as held-to-maturity, as the Company has the positive intent and ability to hold these securities to maturity. Held-to-maturity securities are carried at amortized cost. The amortized cost of debt securities is adjusted using the effective interest rate method for amortization of premiums and accretion of discounts. Amortization and accretion is reported in "Other income, net" in the consolidated income statements. Management periodically evaluates restricted investments for impairment. The assessment of whether impairments have occurred is based on management's case-by-case evaluation of the underlying reasons for the decline in estimated fair value. Management accounts for other-than-temporary impairments of debt securities in accordance with ASC Topic 320, Investments – Debt and Equity Securities . This guidance requires the Company to evaluate whether it intends to sell an impaired debt security or whether it is more likely than not that it will be required to sell an impaired debt security before recovery of the amortized cost basis. If either of these criteria are met, an impairment loss equal to the difference between the debt security's amortized cost and its estimated fair value is recognized in earnings. For impaired debt securities that do not meet these criteria, the Company determines if a credit loss exists with respect to the impaired security. If a credit loss exists, the credit loss component of the impairment (i.e., the difference between the security's amortized cost and the present value of projected future cash flows expected to be collected) is recognized in earnings and the remaining portion of the impairment is recognized as a component of AOCI. Inventories and Supplies — Inventories and supplies primarily consist of spare parts, tires, fuel, and supplies and are stated at lower of cost or market. Cost is determined using the first-in, first-out method. Property and Equipment — Property and equipment are stated at cost. Costs to construct significant assets include capitalized interest incurred during the construction and development period. Expenditures for replacements and improvements are capitalized. Maintenance and repairs are expensed as incurred. Depreciation of property and equipment is calculated on a straight-line basis over the following estimated useful lives: Category Range Facilities and improvements 3 to 40 years Revenue and service equipment 2 to 20 years Furniture and office equipment 3 to 5 years Net gains on the disposal of property and equipment are presented in the consolidated income statements within operating income. Tires on purchased revenue equipment are capitalized along with the related equipment cost when the vehicle is placed in service and depreciated over the life of the vehicle. Replacement tires are classified as inventory and expensed when placed in service. Management evaluates its property and equipment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable in accordance with ASC Topic 360, Property, Plant and Equipment . When such events or changes in circumstances occur, management performs a recoverability test that compares the carrying amount with the projected undiscounted cash flows from the use and eventual disposition of the asset or asset group. An impairment is recorded for any excess of the carrying amount over the estimated fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. Intangible Assets other than Goodwill — The Company's intangible assets other than goodwill primarily consist of acquired customer relationships and trade names. Amortization of acquired customer relationships is calculated on the 150% declining balance method over the estimated useful life of 15 years . The customer relationship contributed to the Company at May 9, 2007 is amortized over 15 years on a straight-line basis. The trade name has an indefinite useful life and is not amortized, but is tested for impairment at least annually, unless events occur or circumstances change between annual tests that would more likely than not reduce the fair value. Management reviews its intangible assets for impairment whenever events or circumstances indicate that the carrying amount of the asset may not be recoverable, in accordance with ASC Topic 350, Intangibles – Goodwill and Other. When such events or changes in circumstances occur, management performs a recoverability test that compares the carrying amount with the projected undiscounted cash flows from the use and eventual disposition of the asset or asset group. An impairment is recorded for any excess of the carrying amount over the estimated fair value, which is generally determined using discounted future cash flows. Goodwill — Management evaluates goodwill on an annual basis as of November 30 th , or more frequently if indicators of impairment exist. The Company assesses qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than the carrying amount. If the Company concludes that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, the Company conducts a two -step quantitative goodwill impairment test. The first step of the quantitative impairment test involves comparing the fair values of the applicable reporting units with their carrying values. Management estimates the fair values of its reporting units using a combination of the income and market approaches. If the carrying amount of a reporting unit exceeds the reporting unit's fair value, then management performs the second step of the quantitative impairment test. The second step of the quantitative impairment test involves comparing the implied fair value of the affected reporting unit's goodwill with the carrying value of that goodwill. Any amount by which the carrying value of the goodwill exceeds its implied fair value is recognized as an impairment loss. Refer to Note 8 for discussion of the results of the Company's annual evaluation as of November 30, 2016 . Claims Accruals — The Company is self-insured for a portion of its risk related to auto liability, workers' compensation, property damage, and cargo damage. Prior to January 1, 2015, the Company was also self-insured for a portion of its employer medical expense. Self-insurance results from buying insurance coverage that applies in excess of a retained portion of risk for each respective line of coverage. The Company accrues for the cost of the uninsured portion of pending claims by evaluating the nature and severity of individual claims and by estimating future claims development based upon historical claims development trends. The actual cost to settle self-insured claim liabilities may differ from our reserve estimates due to legal costs, claims that have been incurred but not reported and various other uncertainties, including the inherent difficulty in estimating the severity of the claims and the potential judgment or settlement amount to dispose of the claim. Fair Value Measurements — See Note 21 for accounting policies and financial information relating to fair value measurements. Contingencies — See Note 17 for accounting policies and financial information related to contingencies. Revenue Recognition — The Company recognizes operating revenues and the related direct costs of such revenue as of the date the freight is delivered, in accordance with ASC Topic 605-20-25-13, Services for Freight-in-Transit at the End of a Reporting Period. The Company recognizes operating lease revenue from leasing tractors and related equipment to owner-operators. Operating lease revenue from rental operations is recognized as earned, which is straight-lined per the rent schedules in the lease agreements. Losses from lease defaults are recognized as offsets to revenue. Stock-based Compensation — The Company accounts for stock-based compensation expense in accordance with ASC Topic 718, Compensation – Stock Compensation. ASC Topic 718 requires that all share-based payments to employees and non-employee directors, including grants of employee stock options, be recognized in the financial statements based upon a grant-date fair value of an award. The Company calculates the number of awards expected to vest as awards granted, less expected forfeitures over the life of the award (estimated at grant date). Compensation expense is recorded based on amortization of the grant-date fair value over a graded vesting period. Unless a material deviation from the assumed forfeiture rate is observed during the term in which the awards are expensed, any adjustment necessary to reflect differences in actual experience is recognized in the period the award becomes payable or exercisable. See Note 19 for additional information relating to the Company's stock compensation plan. Income Taxes — Management accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to operating loss and tax credit carryforwards, as well as differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Net deferred incomes taxes are classified as noncurrent in the consolidated balance sheets. The effect on deferred tax assets and liabilities of changes in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is provided against deferred tax assets if the Company determines it is more likely than not that such assets will not ultimately be realized. The Company does not recognize a tax benefit for uncertain tax positions unless it concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that, in the management's judgment, is greater than 50% likely to be realized. The Company records expected incurred interest and penalties related to unrecognized tax positions in "Income tax expense" in the consolidated income statements. To the extent that such interest and penalties are not ultimately incurred, previously accrued amounts are reduced and reflected as a reduction of the income tax provision.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact January 2017 2017-04: Intangibles – Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment The amendments in this ASU are intended to simplify subsequent measurement of goodwill. The key amendment in the ASU eliminates Step 2 from the goodwill impairment test, in which entities measured a goodwill impairment loss by comparing the implied fair value to the carrying amount of a reporting unit's goodwill. Instead, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value with the carrying amount of a reporting unit and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value. January 2020, prospective Currently under evaluation; not expected to be material January 2017 2017-03: Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323) – Amendments to SEC Paragraphs Pursuant to Staff Announcements at the September 22, 2016 and November 17, 2016 EITF Meetings The amendments in this ASU that are relevant to the Company pertain to disclosures around the impact that recently issued accounting standards will have on the financial statements of a registrant when such standards are adopted in a future period. The amendments in this ASU indicate that the SEC staff expects that if an entity cannot reasonably estimate the impact of an ASU on the financial statements, then the entity should consider additional qualitative disclosures to assist the reader in assessing the significance of the standard's impact on its financial statements. Immediate None - The Company's policy on disclosing recently issued accounting pronouncements is aligned with the amendments in this ASU. November 2016 2016-18: S tatement of Cash Flows – (Topic 230) Restricted Cash (a Consensus of the FASB Emerging Issues Task Force) The amendments in this ASU require transfers between cash and equivalents and restricted cash and equivalents, as well as direct cash receipts into and cash payments made from restricted cash and equivalents to be explained in the statement of cash flows. Restricted cash and restricted cash equivalents are to be included in the beginning and ending cash and cash equivalent balance totals on the statement of cash flows. January 2018; Retrospective Material impact in cash flow presentation to reclassify restricted cash to "net increase/decrease in cash, restricted cash, and equivalents," and adjust the beginning and ending balances. October 2016 2016-17: Consolidation (Topic 810) – Interests Held through Related Parties that are under Common Control This ASU updates the consolidation guidance on how a reporting entity that is a single decision maker of a Variable Interest Entity ('VIE") should treat indirect interests in the entity held through related parties that are under common control when determining whether it is the primary beneficiary of the VIE. The primary beneficiary of a VIE is the reporting entity that has a controlling financial interest in a VIE and, therefore, consolidates the VIE. A reporting entity that has an indirect interest in a VIE if it has a direct interest in a related party that, in turn has a direct interest in the VIE. January 2017, Modified Retrospective No financial statement impact. The Company is not the primary beneficiary of any of its related parties. Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact October 2016 2016-16: Income Taxes (Topic 740) – Intra-entity Transfers of Assets Other than Inventory This ASU states that entities should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs (as compared to current GAAP, which prohibits the recognition of current and deferred income taxes for intra-entity asset transfer until the asset has been sold to an outside party). January 2018, Modified Retrospective Currently under evaluation; not expected to be material since the Company's fixed assets are not typically transferred between legal entities for consideration. August 2016 2016-15: Statement of Cash Flows (Topic 230) – Classification of Certain Cash Receipts and Cash Payments This ASU has several amendments, which are designed to reduce existing diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The ASU addresses eight specific cash flow issues, of which the following are expected to be applicable to Swift: 1) debt prepayment and extinguishment costs, 2) proceeds from settlement of insurance claims, 3) proceeds from settlement of corporate-owned life insurance policies, 4) beneficial interests in securitization transactions, and 5) separately identifiable cash flows and application of the predominance principle. January 2018, Retrospective Currently under evaluation; not expected to be material. June 2016 2016-13: Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments The purpose of this ASU is to amend the current incurred loss impairment methodology with a new methodology that reflects expected credit losses and requires a broader range of reasonable and supportable information to inform credit loss estimates. This is the final credit accounting standard, out of a series, with detailed guidance on the new loss reserve model, Current Expected Credit Loss ("CECL"). Among other provisions, the amendments in the ASU require a financial asset (or group of assets) measured at amortized cost basis to be presented at the net amount expected to be collected. Entities are no longer required to wait until a loss is probable to record it. January 2020, Adoption method varies by amendment Currently under evaluation; not expected to be material. May 2016 2016-12: Revenue from Contracts with Customers (Topic 606) – Narrow-scope Improvements and Practical Expedients The amendments in this ASU clarify certain aspects regarding the collectibility criterion, sales taxes collected from customers, noncash consideration, contract modifications, and completed contracts at transition. It additionally clarifies that retrospective application only requires disclosure of the accounting change effect on prior periods presented, not on the period of adoption. January 2018, Modified retrospective Currently under evaluation (1) April 2016 2016-10: Revenue from Contracts with Customers (Topic 606) – Identifying Performance Obligations and Licensing The amendments in this ASU clarify the following two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance, while retaining the related principles for those areas. The amendments do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) March 2016 2016-08: Revenue from Contracts with Customers (Topic 606) – Principal versus Agent Considerations (Reporting Revenue Gross versus Net) The amendments in this ASU are intended to improve the operability and understandability of the implementation guidance on principal versus agent considerations, but do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact March 2016 2016-09: Compensation – Stock Compensation (Topic 718) – Improvements to Employee Share-based Payment Accounting The amendments in this ASU are intended to simplify various aspects of accounting for stock-based compensation, including income tax consequences, classification of awards as equity or liability, as well as classification of activities within the statement of cash flows. January 2017, Adoption method varies by amendment Expected to be material (2) February 2016 2016-02: Leases (Topic 842) The new standard requires lessees to recognize assets and liabilities arising from both operating and financing leases on the balance sheet. Lessor accounting for leases is largely unaffected by the new guidance. January 2019, Modified retrospective Currently under evaluation; expected to be material, but not yet quantifiable. January 2016 2016-01: Financial Instruments – Overall (Subtopic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities The amendments in this ASU address various aspects of recognition, measurement, presentation, and disclosure of financial instruments. They additionally establish ASC Topic 321 – Investments – Equity Securities , which applies to investments in equity securities and other ownership interests in an entity, including investments in partnerships, unincorporated joint ventures, and limited liability companies. January 2018, Modified retrospective Not expected to be material. August 2015 2015-14: Revenue from Contracts with Customers (Topic 606) – Deferral of the Effective Date This ASU deferred the effective date of ASU 2014-09 (Topic 606) to annual reporting periods beginning after December 15, 2017. January 2018, Modified retrospective Currently under evaluation (1) July 2015 2015-11: Inventory (Topic 330) – Simplifying the Measurement of Inventory The amendments in this ASU simplify subsequent measurement of inventory for all inventory measurement methods, except for last-in-first-out. Entities will be required to measure inventory at the lower of cost and net realizable value, instead of the previously issued guidance of lower of cost or market. January 2017, prospective Not expected to be material. Due to the nature of the Company's inventory balances (spare parts, tires, fuel, and supplies), inventory is predominantly stated at cost. ____________ (1) Management is in the diagnostic phase of assessing the financial and business impacts of implementing ASC Topic 606, Revenue from Contracts with Customers , including identifying revenue sources within the Company's lines of business, reviewing a sample of contracts, and developing a preliminary assessment. Based upon these preliminary procedures, management anticipates that the following key considerations will impact the Company's accounting and reporting under the new standard: • identification of what constitutes a contract in Swift's business practices, • variability in individual contracts, such as customer-specific terms that may vary from the master agreement, • principal versus agent determinations, • timing of revenue recognition (for example, point-in-time versus over time and/or accelerated versus deferred), • single versus multiple performance obligations, • new/changed estimates and management judgments (for example, system estimation of in-transit accruals versus manual estimation), • disaggregation of revenue by category within segments, and • others. Management expects that there will also be changes in sales, contracting, accounting, reporting, tax, debt covenants, and other business processes, policies, and controls, as a result of implementing ASC Topic 606. The Company is currently underway with implementing a new ERP system, which will also affect the implementation process. Based on the information currently available from the diagnostic phase, management cannot yet determine the quantitative impact on the financial statements; however, the impact is expected to be immaterial (potentially with changes only to the timing of revenue recognition between reportable periods, as well as changes in the requirements for accounting policy and other new disclosures). The financial impact is expected to be quantifiable by the time the Company files its first Quarterly Report on Form 10-Q in 2017, at which time the Company will be transitioning into the design and planning phase of implementing ASC Topic 606. Since we are continuing to evaluate the impact of ASC Topic 606, our disclosures around our preliminary assessments are subject to change. (2) The amendments to ASC Topic 718, Compensation – Stock Compensation , that are expected to affect the Company are discussed below. • Accounting for Income Tax Benefits/Deficiencies : All excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) should be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity should also recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company will need to reclassify approximately $16.8 million in historical net tax benefit/deficiency amounts previously recorded within additional paid-in capital into retained earnings/accumulated deficit. Going forward, tax benefit/deficiency amounts will be recorded in net income. • Classification of Excess Tax Benefits on the Statement of Cash Flows : Excess tax benefits should be classified along with other income tax cash flows as an operating activity. Application is permitted to be prospective or retrospective. Current GAAP requires classification within cash flows from financing activities. The Company presents its statement of cash flows using the indirect method, which presents excess tax benefits within cash flows from financing activities and a corresponding offset within the net income reconciliation of cash flows from operating activities. As such, the Company will need to reclassify the excess tax benefit amounts out of cash flows from financing activities and into cash flows from operating activities, upon adoption. Management expects to apply these amendments retrospectively. • Forfeitures : An entity can make an entity-wide accounting policy election to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures when they occur. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company expects to transition to accounting for forfeitures when they occur. This would result in approximately a $2.5 million unfavorable cumulative-effect adjustment to retained earnings/accumulated deficit to catch-up the previously unrecognized stock-based compensation associated with historical assumed forfeiture rates. Going forward, forfeitures will be recorded as favorable adjustments to stock-based compensation as they occur. • Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-withholding purposes : Cash paid by an employer when directly withholding shares for tax-withholding purposes should be classified as a financing activity. Retrospective application is required. Beginning in 2016, the Company began allowing certain members of management to have shares withheld for taxes when their restricted stock awards and performance units vest. As such, upon adopting the amendments in this ASU, the Company will need to present the amounts out of cash flows from operating activities and into cash flows from financing activities for the periods presented. For 2016, the amount was approximately $0.5 million .

Restricted Investments

Restricted Investments	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Restricted Investments	Restricted Investments The following table presents the cost or amortized cost, gross unrealized gains and temporary losses, and estimated fair value of the Company's restricted investments: December 31, 2016 Gross Unrealized Cost or Amortized Cost Gains Temporary Estimated Fair Value (In thousands) United States corporate securities $ 16,432 $ — $ (23 ) $ 16,409 Municipal bonds 4,760 — (6 ) 4,754 Negotiable certificates of deposit 1,525 — — 1,525 Restricted investments, held to maturity $ 22,717 $ — $ (29 ) $ 22,688 December 31, 2015 Gross Unrealized Cost or Amortized Cost Gains Temporary Estimated Fair Value (In thousands) United States corporate securities $ 16,686 $ 2 $ (27 ) $ 16,661 Municipal bonds 4,904 1 (1 ) 4,904 Negotiable certificates of deposit 1,625 — — 1,625 Restricted investments, held to maturity $ 23,215 $ 3 $ (28 ) $ 23,190 Refer to Note 21 for additional information regarding fair value measurements of restricted investments. As of December 31, 2016 , the contractual maturities of the restricted investments were one year or less. There were 42 securities and 36 securities that were in an unrealized loss position for less than twelve months as of December 31, 2016 and 2015 , respectively. The Company did not recognize any impairment losses for the years ended December 31, 2016 , 2015 , or 2014.

Accounts Receivable, net

Accounts Receivable, net	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Accounts Receivable, net	Accounts Receivable, net Accounts receivable balances were as follows: December 31, 2016 2015 (In thousands) Trade customers $ 404,556 $ 415,219 Equipment manufacturers 4,755 6,801 Other 15,731 18,329 Accounts receivable 425,042 440,349 Less: Allowance for doubtful accounts (16,449 ) (17,928 ) Accounts receivable, net $ 408,593 $ 422,421 The following is a rollforward of the allowance for doubtful accounts: December 31, 2016 2015 2014 (In thousands) Beginning balance $ 17,928 $ 9,924 $ 7,504 Provision (Reduction) (1,147 ) 8,004 2,844 Recoveries (332 ) — 89 Write-offs — — (513 ) Ending balance $ 16,449 $ 17,928 $ 9,924 See Note 12 for a discussion of the Company's accounts receivable securitization program and the related accounting treatment.

Assets Held for Sale

Assets Held for Sale	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment Assets Held-for-sale Disclosure [Abstract]
Assets Held for Sale	Assets Held for Sale Assets held for sale balances were: December 31, 2016 2015 (In thousands) Land and facilities $ 288 $ 288 Revenue equipment 6,681 8,796 Assets held for sale $ 6,969 $ 9,084 As of December 31, 2016 and 2015 , assets held for sale are carried at the lower of depreciated cost or estimated fair value, less expected selling costs when the required criteria, as defined by ASC Topic 360, Property, Plant, and Equipment, are satisfied. Depreciation ceases on the date that the held for sale criteria are met. The Company expects to sell these assets within the next 12 months . During 2016, management reassessed the fair value of certain IEL tractors, determining that there was an impairment. Further details are provided in Note 21. The Company did not recognize any impairment losses for the years ended December 31 2015 or 2014 . During the years ended December 31, 2016 and December 31, 2015 , the Company sold no operating properties classified as held for sale. Accordingly, there was no gain or loss on disposal of properties recognized. Gain on disposals of property and equipment recognized in the income statement for those years pertain to revenue equipment. During the year ended December 31, 2014, the Company sold five operating properties classified as held for sale with a carrying value of $14.5 million . As a result, the Company recognized $3.0 million in (pre-tax) gain on disposal of property and equipment in the consolidated income statements.

Notes Receivable

Notes Receivable	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Notes Receivable	Notes Receivable Notes receivable are included in "Current portion of notes receivable" and "Other assets" in the consolidated balance sheets and were comprised of: December 31, 2016 2015 (In thousands) Notes receivable due from owner-operators, with interest rates at 15%, secured by revenue equipment. Terms range from several months to four years $ 10,253 $ 15,725 Other — 24 Notes receivable 10,253 15,749 Less: current portion of notes receivable (6,961 ) (9,817 ) Notes receivable, less current portion $ 3,292 $ 5,932

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets [Text Block]	Goodwill and Other Intangible Assets The following presents the components of goodwill by reportable segment as of December 31, 2016 and 2015 : Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount (In thousands) Truckload goodwill $ 376,998 $ (190,394 ) $ 186,604 Dedicated goodwill 130,742 (64,090 ) 66,652 Goodwill $ 507,740 $ (254,484 ) $ 253,256 There were no impairments identified during annual goodwill impairment testing in 2016 , 2015 , or 2014 . Intangible asset balances were as follows: December 31, 2016 2015 (In thousands) Customer Relationships: Gross carrying value $ 275,324 $ 275,324 Accumulated amortization (190,056 ) (173,242 ) Customer relationships, net 85,268 102,082 Trade Name: Gross carrying value 181,037 181,037 Intangible assets, net $ 266,305 $ 283,119 In conjunction with the 2007 Transactions, definite-lived intangible assets with a gross carrying value of $261.2 million were recorded. Amortization of intangibles consisted of the following: Year Ended December 31, 2016 2015 2014 (In thousands) Amortization of intangible assets related to the 2007 Transactions $ 15,648 $ 15,648 $ 15,648 Amortization related to intangible assets existing prior to the 2007 Transactions 1,166 1,166 1,166 Amortization of intangibles $ 16,814 $ 16,814 $ 16,814 As of December 31, 2016 , management anticipates that the composition and amount of amortization associated with intangible assets will remain at $16.8 million in 2017, and will decrease to $16.3 million in 2018, of which $0.7 million will represent the final amortization of the intangible assets existing prior to the 2007 Transactions. Amortization of intangible assets is expected to be $15.6 million in 2019 through 2021. Actual amounts of amortization expense may differ from estimated amounts due to additional intangible asset acquisitions, impairment of intangible assets, accelerated amortization of intangible assets, and other events.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2016
Accrued Liabilities [Abstract]
Accrued Liabilities	Accrued Liabilities The following table presents the composition of accrued liabilities: December 31, 2016 2015 (In thousands) Employee compensation (1) $ 51,217 $ 55,750 Owner-operator lease purchase reserve 6,229 5,271 Income tax accrual 5,119 2,043 Accrued owner-operator expenses 6,333 6,711 Deferred revenue 2,111 1,740 Fuel and property taxes 6,160 4,076 Accrued interest expense 1,819 1,532 Accrued legal (2) 28,778 2,701 Other (2)(3) 24,946 17,489 Accrued liabilities $ 132,712 $ 97,313 ____________ (1) The Company maintains a 401(k) benefit plan available to all employees who are 21 years of age or older and have completed six months of service. Under the plan, the Company has the option to match employee discretionary contributions up to 3% of an employee's compensation. Employees' rights to employer contributions vest after five years from their date of employment. For the years ended December 31, 2016 , 2015 , and 2014 , the Company's employee benefits expense for matching contributions, included in "Salaries, wages, and employee benefits" in the consolidated income statements, was approximately $5.7 million , $5.6 million , and $4.7 million , respectively. As of December 31, 2016 and 2015 , the balance includes $6.1 million and $5.9 million in matching contributions, respectively, to the plan in respect of such matching contributions. (2) The Company has disaggregated "Accrued legal" from "Other" as of December 31, 2016, and retrospectively adjusted the presentation as of December 31, 2015 for comparative purposes. See Note 17 for further details regarding the Company's legal accruals. (3) Includes the current portion of accrued consulting fees for Jerry Moyes. See Note 23 for further details.

Claims Accruals

Claims Accruals	12 Months Ended
	Dec. 31, 2016
Liability for Claims and Claims Adjustment Expense [Abstract]
Claims Accruals	Claims Accruals Claims accruals represent the uninsured portion of outstanding claims at year-end. The current portion reflects the amount of claims expected to be paid in the following year. The Company's insurance program for workers' compensation, auto and collision liability, physical damage, and cargo damage involves self-insurance with varying risk retention levels. Claims accruals were comprised of the following: December 31, 2016 2015 (In thousands) Auto and collision liability $ 128,643 $ 123,086 Workers’ compensation liability 101,232 92,608 Owner-operator claims liability 11,736 12,304 Cargo damage liability 4,695 5,348 Other liability (1) 286 364 Claims accruals 246,592 233,710 Less: current portion of claims accruals (80,866 ) (84,429 ) Claim accruals, less current portion $ 165,726 $ 149,281 ____________ (1) Includes group medical liability. Effective January 1, 2015, the Company is fully insured on its group medical benefits, subject to contributed premiums. Prior to January 1, 2015, the Company had a $500 thousand specific deductible with an aggregating individual deductible of $150 thousand of each employee health care claim, as well as commercial insurance for the balance.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following table presents the Company's income tax expense: Year Ended December 31, 2016 2015 2014 (In thousands) Current expense: Federal $ 88,689 $ 76,737 $ 81,117 State 10,610 8,826 8,861 Foreign 3,053 8,783 4,107 102,352 94,346 94,085 Deferred (benefit) expense: Federal (31,380 ) 24,097 (4,189 ) State (211 ) 3,419 1,975 Foreign (5,059 ) (2,653 ) (2,397 ) (36,650 ) 24,863 (4,611 ) Income tax expense $ 65,702 $ 119,209 $ 89,474 Rate Reconciliation — The Company's effective tax rate was 30.6% , 37.6% , and 35.7% , for the years ended December 31, 2016 , 2015 , and 2014 , respectively. Expected tax expense is computed by applying the United States federal corporate income tax rate of 35.0% to earnings before income taxes. Actual tax expense differs from expected tax expense as follows: Year Ended December 31, 2016 2015 2014 (In thousands) Computed "expected" tax expense $ 75,239 $ 110,875 $ 87,719 Increase (decrease) in income taxes resulting from: State income taxes, net of federal income tax benefit 6,443 8,745 6,866 Domestic Production Activities Deduction (1) (7,777 ) — — Toll Roads income tax credit (2) (4,082 ) — — Other (4,121 ) (411 ) (5,111 ) Income tax expense $ 65,702 $ 119,209 $ 89,474 ____________ (1) Domestic Production Activities Deduction — Internal Revenue Code Section 199 permits taxpayers to claim a deduction from taxable income attributable to certain domestic production activities such as the development of computer software and the manufacturing of goods. Beginning in 2010 and thereafter, the deduction is equal to 9% of the smaller of a taxpayer’s qualified production activities or taxable income. Due to its increased software development efforts, the Company has elected to take the deduction in the current year and preceding open tax years. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to a domestic production activities deduction on the Company's 2015 federal tax return. The Company also received tax benefits for years ending December 31, 2016, December 31, 2014, and December 31, 2013. The Company generated $6.4 million , $6.2 million , $6.2 million , and $3.4 million in domestic production activities deductions for the development of computer software in 2016, 2015, 2014, and 2013, respectively. This resulted in approximately $2.2 million , $2.2 million , $2.2 million , and $1.2 million in tax benefits in 2016, 2015, 2014, and 2013, respectively. (2) Toll roads income tax credit — Trans-Mex, our Mexico trucking subsidiary, qualified for an income tax credit equal to 50% of the qualified tolls paid. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to the toll road income tax credit reported on the 2015 income tax return. Trans-Mex also will claim a toll road income tax credit for 2016. Trans-Mex paid $5.6 million and $6.5 million in qualifying tolls during 2016 and 2015, respectively. This resulted in approximately $1.8 million and $2.3 million in tax benefits in 2016 and 2015, respectively. Deferred Income Taxes — The components of the net deferred tax asset (liability) included in "Deferred income taxes" in the consolidated balance sheets were: December 31, 2016 2015 (In thousands) Deferred tax assets: Self-insurance accruals $ 73,654 $ 66,949 Allowance for doubtful accounts 8,036 11,448 Amortization of stock options 6,397 8,923 Accrued liabilities 15,366 1,773 Vacation accrual 5,358 4,990 Other 8,940 11,589 Total deferred tax assets 117,751 105,672 Valuation allowance — — Total deferred tax assets, net 117,751 105,672 Deferred tax liabilities: Property and equipment, principally due to differences in depreciation (420,975 ) (434,802 ) Prepaid taxes, licenses, and permits deducted for tax purposes (13,284 ) (14,083 ) Cancellation of debt (3,747 ) (5,622 ) Intangible assets (106,143 ) (110,546 ) Other (1,324 ) (4,451 ) Deferred tax liabilities (545,473 ) (569,504 ) Deferred income taxes $ (427,722 ) $ (463,832 ) Valuation Allowance — As of December 31, 2016 , the Company had federal and state net operating loss carryforwards remaining, with estimated tax effects of $0.5 million and $0.1 million , respectively. The federal and state net operating losses will expire at various times between 2017 and 2030 . The Company has not established a valuation allowance as it has been determined that, based upon available evidence, a valuation allowance is not required. Management asserts that it is more likely than not that the results of future operations will generate sufficient taxable income to realize the deferred tax assets. All other deferred tax assets are expected to be realized and utilized by continued profitability in future periods. Cumulative Undistributed Foreign Earnings — United States income and foreign withholding taxes have not been provided on approximately $36.3 million of cumulative undistributed earnings of foreign subsidiaries as of December 31, 2016. The earnings are considered to be permanently reinvested outside the United States. As such, under current law, the Company is not required to provide United States income taxes on these earnings until they are repatriated in the form of dividends or otherwise. Unrecognized Tax Benefits — The Company's unrecognized tax benefits as of December 31, 2016 would favorably impact our effective tax rate if subsequently recognized. The following is a rollforward of our unrecognized tax benefits: Year Ended December 31, 2016 2015 2014 (In thousands) Unrecognized tax benefits at beginning of year $ 1,739 $ 1,739 $ 2,385 Increases for tax positions taken prior to beginning of year — — 95 Decreases for tax positions taken prior to beginning of year (975 ) — (741 ) Unrecognized tax benefits at end of year $ 764 $ 1,739 $ 1,739 During the year the Company determined that certain state income tax positions were no longer uncertain due to statute of limitations, which represents the above decreases in unrecognized tax benefits. The Company does not anticipate a decrease of unrecognized tax benefits during the next twelve months. Tax Examinations — Certain of the Company's subsidiaries are currently under examination by various state jurisdictions for tax years ranging from 2012 to 2015 . At the completion of these examinations, management does not expect any adjustments that would have a material impact on the Company's effective tax rate. Years subsequent to 2012 remain subject to examination. Interest and Penalties — Accrued interest and penalties as of December 31, 2016 and 2015 were approximately $0.4 million and $1.4 million , respectively. Regulatory Developments — In December 2014, United States President, Barack Obama, signed the Tax Increase Prevention Act of 2014 ("TIPA"). Among other things, TIPA extended 50% bonus depreciation and the Work Opportunity Tax Credit ("WOTC"). During the first three quarters of 2014, the Company did not include 50% bonus depreciation or WOTC in its income tax provision, as these items were not allowed in 2014 prior to the passing of the TIPA Act. Income tax calculations performed for the year ended December 31, 2014 included the full year's adjustment for 50% bonus depreciation and WOTC, as TIPA allowed for retrospective inclusion. In December 2015, President Obama signed the Protecting Americans from Tax Hikes ("PATH") Act of 2015. Among other things, PATH extended 50% bonus depreciation and WOTC. During the first three quarters of 2015, the Company did not include 50% bonus depreciation or WOTC in its income tax provision, as these items were not allowed in 2015 prior to the passing of the PATH Act. Income tax calculations performed for the year ended December 31, 2015 include the full year's adjustment for 50% bonus depreciation and WOTC, as PATH allowed for retrospective inclusion.

Accounts Receivable Securitizat

Accounts Receivable Securitization	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing of Financial Assets [Abstract]
Accounts Receivable Securitization	Accounts Receivable Securitization On December 10, 2015, SRCII, a wholly-owned subsidiary of the Company, entered into the 2015 RSA, which further amends the 2013 RSA. The parties to the 2015 RSA include SRCII as the seller, Swift Transportation Services, LLC as the servicer, the various conduit purchasers, the various related committed purchasers, the various purchaser agents, the various letters of credit participants, and PNC Bank, National Association as the issuing bank of letters of credit and as administrator. Pursuant to the 2015 RSA, the Company's receivable originator subsidiaries sell, on a revolving basis, undivided interests in all of their eligible accounts receivable to SRCII. In turn, SRCII sells a variable percentage ownership interest in the eligible accounts receivable to the various purchasers. The facility qualifies for treatment as a secured borrowing under ASC Topic 860, Transfers and Servicing . As such, outstanding amounts are classified as liabilities on the Company's consolidated balance sheets. Refer to Note 21 for information regarding the fair value of the 2015 RSA. The following table summarizes the key attributes of the current and previous securitization programs: 2015 RSA 2013 RSA (Dollars in thousands) Effective December 2015 June 2013 Borrowing capacity (1) $400,000 $375,000 Final maturity date January 10, 2019 July 13, 2016 Unused commitment fee rate 35 basis points 35 basis points Program fees on outstanding balances one-month LIBOR + 90 basis points one-month LIBOR + 95 basis points ____________ (1) The 2015 RSA has an accordion option to increase the maximum borrowing capacity by up to an additional $75.0 million , subject to participation by the Purchasers. The 2013 RSA borrowing capacity included a $50.0 million accordion option, which was exercised in September 2014. As of December 31, 2016 and 2015 , interest accrued on the aggregate principal balance at a rate of 1.3% and 1.0% , respectively. Program fees and unused commitment fees are recorded in "Interest expense" in the consolidated income statements. The Company incurred program fees of $4.4 million , $3.5 million , and $3.5 million , during the years ended December 31, 2016 , 2015 , and 2014 , respectively. The 2015 RSA is subject to customary fees and contains various customary affirmative and negative covenants, representations and warranties, and default and termination provisions. Collections on the underlying receivables by the Company are held for the benefit of SRCII and the various purchasers and are unavailable to satisfy claims of the Company and its subsidiaries.

Debt And Financing

Debt And Financing	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt And Financing	Debt and Financing Other than the Company's accounts receivable securitization as discussed in Note 12 and its outstanding capital lease obligations as discussed in Note 15 , the Company's long-term debt consisted of the following: December 31, 2016 2015 (In thousands) 2015 Agreement: New Term Loan A, due July 2020, net of $1,338 and $1,695 DLCs as of December 31, 2016 and 2015 respectively (1) $ 492,912 $ 668,055 Other 8,893 11,122 Long-term debt 501,805 679,177 Less: current portion of long-term debt, net of $0 and $68 DLCs as of December 31, 2016 and 2015 respectively (8,459 ) (35,514 ) Long-term debt, less current portion $ 493,346 $ 643,663 December 31, 2016 2015 (In thousands) Long-term debt $ 501,805 $ 679,177 Revolving line of credit, due July 2020 (2) 130,000 200,000 Long-term debt, including revolving line of credit $ 631,805 $ 879,177 ____________ (1) Refer to Note 21 for information regarding the fair value of debt. (2) The Company also had outstanding letters of credit under the New Revolver, primarily related to workers' compensation and self-insurance liabilities of $97.0 million at December 31, 2016 and $95.0 million at December 31, 2015 . Credit Agreements 2015 Agreement — On July 27, 2015, the Company entered into the 2015 Agreement, which replaced the 2014 Agreement, including the $450.0 million Old Revolver ( zero outstanding at closing), $500.0 million Old Term Loan A ( $485.0 million outstanding at closing), and $400.0 million Term Loan B ( $395.0 million outstanding at closing). The 2015 Agreement includes a New Revolver and a New Term Loan A. Upon closing, the $680.0 million in proceeds from the New Term Loan A, a $200.0 million draw on the New Revolver and $4.9 million cash on hand were used to pay off the then-outstanding balances of the Old Term Loan A and Term Loan B, including accrued interest and fees under the 2014 Agreement, as well as certain transactional fees associated with the 2015 Agreement. The following table presents the key terms of the 2015 Agreement: 2015 Agreement New Term Loan A New Revolver (2) (Dollars in thousands) Maximum borrowing capacity $680,000 $600,000 Final maturity date July 27, 2020 July 27, 2020 Interest rate base LIBOR LIBOR LIBOR floor —% —% Interest rate minimum margin (1) 1.50% 1.50% Interest rate maximum margin (1) 2.25% 2.25% Minimum principal payment — amount (3) $6,625 $— Minimum principal payment — frequency Quarterly Once Minimum principal payment — commencement date (3) December 31, July 27, ____________ (1) The interest rate margin for the New Term Loan A and New Revolver is based on the Company's consolidated leverage ratio. As of December 31, 2016 , interest accrued at 2.18% on the New Term Loan A and 2.18% on the New Revolver. As of December 31, 2015 , interest accrued at 2.12% on the New Term Loan A and 2.08% on the New Revolver. (2) The commitment fee for the unused portion of the New Revolver is based on the Company's consolidated leverage ratio, and ranges from 0.25% to 0.35% . As of December 31, 2016 , commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.50% . As of December 31, 2015 , commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.75% . (3) Commencing in March 2017, the minimum required quarterly payment on the New Term Loan A is $12.3 million , at which it would remain until final maturity. However, as of January 2017, the Company voluntarily prepaid all minimum quarterly principal payments through final maturity. The New Revolver and New Term Loan A of the 2015 Agreement contain certain financial covenants with respect to a maximum leverage ratio and a minimum consolidated interest coverage ratio. The 2015 Agreement provides flexibility regarding the use of proceeds from asset sales, payment of dividends, stock repurchases, and equipment financing. In addition to the financial covenants, the 2015 Agreement includes customary events of default, including a change in control default and certain affirmative and negative covenants, including, but not limited to, restrictions, subject to certain exceptions, on incremental indebtedness, asset sales, certain restricted payments (including dividends and stock repurchases), certain incremental investments or advances, transactions with affiliates, engagement in additional business activities, and prepayments of certain other indebtedness. Borrowings under the 2015 Agreement are secured by substantially all of the assets of the Company and are guaranteed by Swift Transportation Company, IEL, Central Refrigerated Transportation, LLC and its subsidiaries, Swift Transportation Co., LLC and its domestic subsidiaries (other than its captive insurance subsidiaries, driver academy subsidiary, and its bankruptcy-remote special purpose subsidiary). 2014 Agreement — The Company entered into the 2014 Agreement on June 9, 2014, which was subsequently replaced by the 2015 Agreement. The 2014 Agreement included the Old Term Loan A, a first lien Term Loan B tranche, and the Old Revolver. The 2014 Agreement replaced the then-existing revolving credit line, as well as the first lien term loan B-1 and B-2 tranches of the 2013 Agreement, which had outstanding principal balances at closing of $229.0 million and $370.9 million , respectively. Upon closing, the Company drew $164.0 million on the Old Revolver and $50.0 million on the Old Term Loan A. The Company subsequently drew the remaining $450.0 million available on the Old Term Loan A to facilitate redemption of the Senior Notes in November 2014. The following table presents the key terms of the 2014 Agreement: Insert Title Here 2014 Agreement Old Term Loan A Term Loan B Old Revolver (2) (Dollars in thousands) Maximum borrowing capacity $500,000 $400,000 $450,000 Final maturity date June 9, 2019 June 9, 2021 June 9, 2019 Interest rate base LIBOR LIBOR LIBOR LIBOR floor —% 0.75% —% Interest rate minimum margin (1) 1.50% 3.00% 1.50% Interest rate maximum margin (1) 2.25% 3.00% 2.25% Minimum principal payment — amount (3) $5,625 $1,000 $— Minimum principal payment — frequency Quarterly Quarterly Once Minimum principal payment — commencement date (3) March 31, 2015 June 30, 2014 June 30, 2019 ____________ (1) Interest rate margins on the Old Term Loan A and Old Revolver were based on the Company's consolidated leverage ratio. Additionally, after December 31, 2014, interest rate margins on the Term Loan B were determined by the Company's consolidated leverage ratio, ranging from 2.75% to 3.00% . (2) The commitment fee for the unused portion of the Old Revolver was also based on the Company's consolidated leverage ratio, and ranged from 0.25% to 0.35% . (3) Commencing in March 2017, the minimum principal payment amount on the Old Term Loan A would have been $11.3 million . Senior Notes In November 2014, the Company redeemed, in full, the remaining $428.1 million face value of its Senior Notes. This was primarily funded with the proceeds from the Company's Old Term Loan A. The Company paid 105.0% of face value, plus accrued and unpaid interest, to call the Senior Notes. While the redeemed Senior Notes incurred interest at 10.0% , the source of funds from the Old Term Loan A incurred interest at LIBOR plus applicable margin of 1.50% to 2.25% . The November 2014 redemption followed a series of open market purchases that occurred in the first nine months of 2014, in which the Company used cash on hand to repurchase $71.9 million in principal of the Senior Notes. Including the November 2014 redemption, the Company repurchased the entire $500.0 million in principal of the Senior Notes during 2014, at an average price of 105.58% of face value. Payment of principal and interest on the Senior Notes was previously guaranteed by certain of the Company's 100% owned domestic subsidiaries. Pursuant to the terms of the indenture governing the Senior Notes, the guarantees were subject to release at which time the subsidiaries no longer had indebtedness that would have required a guarantee. Thus, the Company's redemption of the Senior Notes on November 15, 2014, released the related guarantee. Loss on Debt Extinguishment The Company incurred no losses on debt extinguishment during the year ended December 31, 2016 . For the year ended December 31, 2015 , the Company incurred $9.6 million in losses on debt extinguishment, reflecting the write-off of the unamortized OID and deferred financing fees related to the 2014 Agreement, which was replaced by the 2015 Agreement. For the year ended December 31, 2014 , the Company incurred $39.9 million in losses on debt extinguishment related to the Company's redemption of its Senior Notes and the replacement of the 2013 Agreement with the 2014 Agreement.

Deferred Loan Costs

Deferred Loan Costs	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Deferred Loan Costs	Deferred Loan Costs As discussed in Note 1 , DLCs related to the Company's New Term Loan A and accounts receivable securitization are now netted against the face amount of the debt, pursuant to the amendments to ASC 835-30 in ASU 2015-03. DLCs related to the New Revolver are reported in "Other assets." The following table presents the classification of DLCs in the Company's consolidated balance sheets: December 31, 2016 2015 (In thousands) ASSETS: Other assets $ 1,169 $ 1,496 LIABILITIES: Current portion of long-term debt — 68 Long-term debt, less current portion 1,338 1,627 Accounts receivable securitization 715 1,073 Total DLCs $ 3,222 $ 4,264

Leases

Leases	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Leases	Leases The Company finances a portion of its revenue equipment under capital and operating leases and certain terminals under operating leases. Capital Leases (as Lessee) — The Company's capital leases are typically structured with balloon payments at the end of the lease term equal to the residual value the Company is contracted to receive from certain equipment manufacturers upon sale or trade back to the manufacturers. If the Company does not receive proceeds of the contracted residual value from the manufacturer, the Company is still obligated to make the balloon payment at the end of the lease term. Certain leases contain renewal or fixed price purchase options. The present value of obligations under capital leases is included under "Current portion of capital lease obligations" and "Capital lease obligations, less current portion" in the consolidated balance sheets. As of December 31, 2016 , the leases were collateralized by revenue equipment with a cost of $319.8 million and accumulated amortization of $97.0 million . As of December 31, 2015 , the leases were collateralized by revenue equipment with a cost of $357.8 million and accumulated amortization of $90.1 million . Amortization of the equipment under capital leases is included in "Depreciation and amortization of property and equipment" in the Company's consolidated income statements. Operating Leases (as Lessee) — The revenue equipment leases generally include a purchase option exercisable at the completion of the lease. The Company does not currently guarantee residual values under its operating lease agreements for revenue equipment. Rent expense related to operating leases was $226.3 million , $240.5 million , and $229.3 million for the years ended December 31, 2016 , 2015 , and 2014 , respectively. As of December 31, 2016 , annual future minimum lease payments for all noncancelable leases were: Operating Capital (In thousands) 2017 $ 203,463 $ 77,925 2018 144,205 49,965 2019 92,065 60,212 2020 44,592 13,669 2021 23,231 29,890 Thereafter 48,813 17,268 Future minimum lease payments $ 556,369 $ 248,929 Less: amounts representing interest (14,993 ) Present value of minimum lease payments 233,936 Less: current portion (72,473 ) Capital lease obligations, less current portion $ 161,463 Operating Leases (as Lessor) — The Company's wholly-owned financing subsidiaries lease revenue equipment to the Company's owner-operators under operating leases. Annual future minimum lease payments receivable under operating leases for the periods noted below were: (In thousands) 2017 $ 109,077 2018 64,615 2019 27,739 2020 9,752 2021 9 Thereafter — Future minimum lease payments receivable $ 211,192 Lease classification is determined based on minimum rental payments per the agreement, including residual value guarantees, when applicable, as well as receivables due to the Company upon default or cross-default. When owner-operators default on their leases, the Company typically re-leases the equipment to other owner-operators. As such, future minimum lease payments reflect original leases and re-leases.

Purchase Commitments

Purchase Commitments	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Purchase Commitments	Purchase Commitments As of December 31, 2016 , the Company's outstanding commitments to acquire revenue equipment were as follows: • year-ended December 31, 2017 : $270.7 million ( $265.3 million of which were tractor commitments), and • thereafter: none. The Company has the option to cancel tractor purchase orders with 60 to 90 days ' notice prior to the scheduled production, although the notice period has lapsed for approximately 28.6% of the tractor commitments outstanding as of December 31, 2016 . These purchases are expected to be financed by the combination of operating leases, capital leases, debt, proceeds from sales of existing equipment, and cash flows from operations. As of December 31, 2016 , the Company's outstanding purchase commitments to acquire facilities and non-revenue equipment were as follows: • year-ended December 31, 2017 : $13.6 million , • years-ended December 31, 2018 to 2019 : $8.8 million , and • thereafter: $3.9 million Factors such as costs and opportunities for future terminal expansions may change the amount of such expenditures.

Contingencies and Legal Proceed

Contingencies and Legal Proceedings	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Legal Proceedings	Contingencies and Legal Proceedings Accounting Policy The Company is involved in certain claims and pending litigation primarily arising in the normal course of business. The majority of these claims relate to workers' compensation, auto collision and liability, physical damage, and cargo damage. The Company accrues for the uninsured portion of claims losses and the gross amount of other losses when the likelihood of the loss is probable and the amount of the loss is reasonably estimable. These accruals are based on management's best estimate within a possible range of loss. When there is no amount within the range of loss that appears to be a better estimate than any other amount, then management accrues to the low end of the range. Legal fees are expensed as incurred. When it is reasonably possible that exposure exists in excess of the related accrual (which could be no accrual), management discloses an estimate of the possible loss or range of loss, unless an estimate cannot be determined. If the likelihood of a loss is remote, the Company does not accrue for the loss. However if the likelihood of a loss is remote, but it is at least reasonably possible that one or more future confirming events may materially change management's estimate within twelve months from the date of the financial statements, management discloses an estimate of the possible loss or range of loss, unless an estimate cannot be determined. Legal Proceedings Information is provided below regarding the nature, status, and contingent loss amounts, if any, associated with the Company's pending legal matters. There are inherent uncertainties in these legal matters, some of which are beyond management's control, making the ultimate outcomes difficult to predict. Moreover, management's views and estimates related to these matters may change in the future, as new events and circumstances arise and the matters continue to develop. For the matters below, an estimate of the possible loss or range of loss cannot be determined for certain cases because, among other reasons, (1) the proceedings are in various stages that do not allow for assessment; (2) damages have not been sought; (3) damages are unsupported and/or exaggerated; (4) there is uncertainty as to the outcome of pending appeals; and/or (5) there are significant factual issues to be resolved. Based on currently available information, and in certain cases, advice of outside counsel, management does not believe that loss contingencies arising from pending matters will have a material adverse effect on the Company's overall financial position, after taking into consideration any existing accruals. However, actual outcomes could be material to the Company's operating results or liquidity for any particular period. EMPLOYEE COMPENSATION AND PAY PRACTICES MATTERS Aggregate information regarding accruals for the below employee compensation and pay practices matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $1.0 million $— - $0.3 million For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made. California Private Attorneys General Act ("PAGA") Class Action The plaintiff alleges that the Company violated California law by failing to timely pay wages and failing to reimburse employees for business expenses. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Theron Christopher (1) Swift Transportation Co. of Arizona, LLC July 8, 2016 Superior Court of California, County of Riverside Recent Developments and Current Status The PAGA matter is in its initial phases and is expected to move into discovery. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Wage, Meal, and Rest: Driver Class Actions The plaintiffs generally allege one or more of the following: that the Company 1) failed to pay the California minimum wage; 2) failed to provide proper meal and rest periods; 3) failed to timely pay wages upon separation from employment; 4) failed to pay for all hours worked; 5) failed to pay overtime; 6) failed to properly reimburse work-related expenses; and 7) failed to provide accurate wage statements. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in John Burnell (1) Swift Transportation Co., Inc March 22, 2010 United States District Court for the Central District of California James R. Rudsell (1) Swift Transportation Co. of Arizona, LLC and Swift Transportation Company April 5, 2012 United States District Court for the Central District of California Lawrence Peck (1) Swift Transportation Co. of Arizona, LLC September 25, 2014 United States District Court for the Central District of California Lawrence Peck (1)(2) Swift Transportation Co. of Arizona, LLC, et al. November 20, 2014 Superior Court of California, County of Riverside Sadashiv Mares (1) Swift Transportation Co. of Arizona, LLC February 27, 2015 United States District Court for the Central District of California Rafael McKinsty (1) Swift Transportation Co. of Arizona, LLC, et al. April 15, 2015 United States District Court for the Central District of California Thor Nilsen (1) Swift Transportation Co. of Arizona, LLC October 15, 2015 United States District Court for the Central District of California Recent Developments and Current Status Before and during 2016, the Rudsell, Peck, Peck PAGA, Mares, McKinsty, and Nilsen complaints were stayed, pending resolution of earlier-filed cases. In May 2016, the Burnell plaintiffs were denied class certification. Their subsequent petition to appeal the decertification order was also denied. Following the Burnell plaintiffs' failure to certify the class, the stays on certain cases were lifted. Those cases are now in discovery. Based on the current procedural nature of the cases, the final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Wage, Meal, and Rest: Yard Hostler Class Actions The plaintiffs, representing yard hostlers employed by the Company in California, generally allege one or more of the following: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime and doubletime wages required by California law; 3) failed to provide accurate, itemized wage statements; 4) failed to timely pay wages upon separation from employment; 5) failed to reimburse for business expenses; and 6) failed to provide proper meal and rest periods. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Grant Fritsch (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Company January 28, 2016 Superior Court of California, County of San Bernardino Bill Barker, Tab Bachman, and William Yingling (1) Swift Transportation Company of Arizona, LLC April 1, 2016 United States District Court for the Eastern District of California Recent Developments and Current Status The Barker and Fritsch complaints are currently in discovery. The Company retains all of its defenses against liability and damages related to these lawsuits. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of these matters and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. National Customer Service Misclassification Class Action The plaintiff, a former Customer Service Representative IV, alleges that the Company failed to pay overtime under the FLSA. Additionally, with respect to California state law, the plaintiff alleges that the Company: 1) failed to pay overtime; 2) failed to pay timely final wages; 3) failed to provide meal and rest periods; and 4) violated the unfair competition law. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Salvador Castro (1) Swift Transportation Co. of Arizona, LLC May 11, 2016 United States District Court for the Central District of California Recent Developments and Current Status Castro, along with five other former Customer Service Representative IV employees opted into this collective action lawsuit, which was being pursued under the FLSA. In addition to the Castro collective action, thirteen Customer Service Representative IV employees pursued similar claims in individual arbitrations. The parties conducted three arbitrations regarding the individual claimants. The parties agreed to mediation, which was held in January 2017. The parties are currently finalizing a global settlement of the collective action and the individual arbitrations. Arizona Fair Labor Standards Act Class Action The plaintiff alleges that the Company violated the FLSA by failing to pay its trainee drivers minimum wage for all work performed and by failing to pay overtime. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Pamela Julian (1) Swift Transportation Inc., et al. December 29, 2015 United States District Court for the District of Arizona Recent Developments and Current Status In March 2016, the Company filed a motion to dismiss the plaintiff's overtime claims, which was granted by the district court in May 2016. The plaintiff recently filed a Motion for Conditional Class Certification, which the Company intends to oppose. The Company retains all of its defenses against liability and damages for the remaining claims. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Washington Overtime Class Actions The plaintiffs allege one or more of the following, pertaining to Washington state-based drivers: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime; 3) failed to pay all wages due at established pay periods; 4) failed to provide proper meal and rest periods; 5) failed to provide accurate wage statements; and 6) unlawfully deducted from employee wages. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Troy Slack (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation September 9, 2011 United States District Court for the Western District of Washington Julie Hedglin (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation January 14, 2016 United States District Court for the Western District of Washington Recent Developments and Current Status The parties in the Slack matter are finishing discovery and the next step will be for the parties to file dispositive motions. The case is scheduled for trial in September 2017. The Hedglin matter is currently in discovery. The Company retains all of its defenses against liability and damages for both matters. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. ___________ (1) Individually and on behalf of all others similarly situated. (2) Peck PAGA complaint. OWNER-OPERATOR MATTERS Aggregate information regarding accruals for the below owner-operator matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $25.0 million $— - $44.0 million For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made. Arizona Owner-operator Class Action The putative class alleges that the Company improperly compensated owner-operators (later expanding the class to include employee drivers) using the contracted and industry standard remuneration based upon dispatched miles, instead of using a method of calculating mileage that the plaintiffs allege would be more accurate. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Leonel Garza (1) Swift Transportation Co., Inc. January 30, 2004 Arizona Supreme Court Recent Developments and Current Status The original trial court's decision was to deny class certification of the owner-operators, which was reversed and reinstated several times by various courts prior to 2016. The class is currently certified, based on an appellate court's decision from July 2016. The Company filed a petition for review with the Arizona Supreme Court in August 2016, which was denied in January 2017. The matter will now proceed in the Maricopa County Superior Court. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Ninth Circuit Owner-operator Misclassification Class Action The putative class alleges that the Company misclassified owner-operators as independent contractors in violation of the FLSA and various state laws, and that such owner-operators should be considered employees. The lawsuit also raises certain related issues with respect to the lease agreements that certain owner-operators have entered into with IEL. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Joseph Sheer, Virginia Van Dusen, Jose Motolinia, Vickii Schwalm, Peter Wood (1) Swift Transportation Co., Inc., Interstate Equipment Leasing, Inc., Jerry Moyes, and Chad Killebrew December 22, 2009 Unites States District Court of Arizona and Ninth Circuit Court of Appeals Recent Developments and Current Status For several years, the parties have been arguing over the proper venue in which to proceed. The plaintiffs argue that they signed contracts of employment, thus exempting them from arbitration under the Federal Arbitration Act, and claim that their case should be heard in court by a judge. The Company takes the position that these individuals signed independent contractor agreements and therefore can properly be required to submit their claims to arbitration. In January 2017, the district court issued an order finding that the plaintiffs had signed contracts of employment and thus the case could properly proceed in court. The Company has appealed this decision to the Ninth Circuit and will seek to stay the district court case, pending resolution of the appeal. The Company intends to vigorously defend against any proceedings. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Utah Collective and Individual Arbitration The plaintiffs allege that the Central Parties (defined below) misclassified owner-operator drivers as independent contractors and were therefore liable to these drivers for minimum wages and other employee benefits under the FLSA. The complaint also alleges a federal forced labor claim under U.S.C. §1589 and §1595, as well as fraud and other state-law claims. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Gabriel Ciluffo, Kevin Shire, and Bryan Ratterree (1)(2) Central Refrigerated Service, Inc., Central Leasing, Inc., Jon Isaacson, and Jerry Moyes (the "Central Parties"), as well as Swift Transportation Company June 1, 2012 American Arbitration Association Recent Developments and Current Status In June 2016, mediation commenced, but there was ultimately no settlement of the matter. In October 2016, the arbitrator ruled that approximately 1,300 Central Refrigerated Service, Inc. drivers were misclassified as independent contractors, and should have been compensated as employees. The arbitrator ruled that damages could be assessed in a collective proceeding and declined to decertify the collective proceeding. Based on the October 2016 arbitration ruling, the Company increased its accrual related to this matter. A damages trial is scheduled for April 2017. No trial date on the claimants' damages has been set by the arbitrator. The Company and the Central Parties dispute the arbitrator's rulings to date and intend to continue to vigorously defend against the plaintiffs' claims in both the collective action and individual proceedings. The likelihood that a loss has been incurred is probable. ___________ (1) Individually and on behalf of all others similarly situated. (2) In addition to the collective arbitration that is pending before the American Arbitration Association ("AAA"), the named plaintiffs, along with approximately 325 other owner-operators, have initiated a series of individual, bilateral proceedings against the Central Parties with the AAA. Discovery is commencing in these individual cases, which are pending before various separate arbitrators. A sample of these cases will be litigated and proceed to hearing, while the remaining cases will be stayed. Trials for the sample cases are expected to occur in the second quarter of 2017. EMPLOYEE HIRING PRACTICES MATTERS Aggregate information regarding accruals for the below employee hiring practices matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $— $— - $— It is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated for these matters. Indiana Fair Credit Reporting Act Class Action The plaintiff alleges that Central Refrigerated Service, Inc. violated the Fair Credit Reporting Act by failing to provide job applicants with adverse action notices and copies of their consumer reports and statements of rights. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Melvin Banks (1) Central Refrigerated Service, Inc. March 18, 2015 United States District Court for the District of Arizona Recent Developments and Current Status The first phase of discovery, regarding potential for identifying and certifying a class of affected job applicants, has been completed. The parties are currently completing a class certification briefing and the Company filed a Motion for Summary Judgment. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Class and Collective Action for Pre-employment Physical Testing The plaintiff alleges that pre-employment tests of physical strength administered by a third party on behalf of Central Refrigerated Service, Inc. had an unlawfully discriminatory impact on female applicants and applicants over the age of 40. The suit seeks damages under Title VII of the Civil Rights Act of 1964, the age Discrimination Act, and parallel California state law provisions, including the California Fair Employment and Housing Act. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Robin Anderson (1) Central Refrigerated Service, Inc., Workwell Systems, Inc., and Swift Transportation Company October 6, 2014 United States District Court for the Central District of California Recent Developments and Current Status Litigation is at a very preliminary stage and no trial date has been set. There is no information available regarding the number of potential members of the putative class or collective actions. The Company intends to vigorously defend against the merits of the plaintiff's claims and to oppose certification of any class of plaintiffs. The final disposition of this case and the financial impact cannot be determined at this time. The likelihood that a loss has been incurred is remote. ___________ (1) Individually and on behalf of all others similarly situated. Other Contingencies Demand for Inspection of Books and Records and Stockholder Derivative Lawsuit — During 2016, the Company received several shareholder demands requesting to inspect the Company's books and records, pursuant to Section 220 of the Delaware General Corporation Law. The demands relate to the shareholders' alleged investigation pertaining to whether the Board and Jerry Moyes have breached their fiduciary duties with respect to matters that have been publicly disclosed concerning the Company's securities trading policy, limitations on the pledging of Company stock on margin, share repurchases, the status of Board members as independent directors and other related matters. The Company has responded to the shareholders' requests received thus far. On February 9, 2016, a civil lawsuit was filed in the Court of Chancery of the State of Delaware (captioned as: Shiva Stein derivatively on behalf of Swift Transportation Company v. Jerry Moyes et al. and Swift Transportation Company as nominal defendant (the "Complaint")). The Complaint, initially filed as a confidential filing, is a purported derivative action alleging that the individual members of the Company's Board breached their fiduciary duties related to the Company's administration of its Securities Trading Policy and certain compensation actions related to Mr. Moyes. Any future disposition or resolution of these matters cannot be determined at this time. Environmental — The Company's tractors and trailers are involved in motor vehicle accidents, and experience damage, mechanical failures, and cargo issues as an incidental part of its normal course of operations. From time to time, these matters result in the discharge of diesel fuel, motor oil, or other hazardous materials into the environment. Depending on local regulations and who is determined to be at fault, the Company is sometimes responsible for the clean-up costs associated with these discharges. As of December 31, 2016, the Company's estimate for its total legal liability for all such clean-up and remediation costs was approximately $0.6 million in the aggregate for all current and prior year claims.

Common Stock

Common Stock	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Common Stock	Common Stock Holders of Class A common stock are entitled to one vote per share , while holders of Class B common stock are entitled to two votes per share on any matter to be voted on by our stockholders. Holders of Class A and Class B common stock vote together as a single class on all matters submitted to a vote of stockholders, unless otherwise required by law, except that a separate vote of each class would be required for: • any merger or consolidation in which holders of shares of Class A common stock receive consideration that is not identical to holders of shares of Class B common stock; • any amendment of Swift Transportation Company's amended and restated certificate of incorporation or amended and restated bylaws that alters the relative rights of its common stockholders; and • any increase in the authorized number of shares of Class B common stock or the issuance of shares of Class B common stock, other than such increase or issuance required to effect a stock split, stock dividend, or recapitalization pro rata with any increase or issuance of Class A common stock. Share Repurchase Programs The following table presents our repurchases of our Class A common stock under the respective share repurchase programs, net of advisory fees: Year Ended December 31, As of December 31, Share Repurchase Program 2016 2015 2016 Authorized Amount Board Approval Date Shares Amount Shares Amount Amount Remaining (In thousands) $100,000 September 24, 2015 2,221 $ 30,000 4,176 $ 70,000 $ — $150,000 February 22, 2016 5,162 $ 87,119 — $ — $ 62,881 7,383 $ 117,119 4,176 $ 70,000 $ 62,881 No share repurchases were made during the year ended December 31, 2014 . Common Stock Transactions — Jerry Moyes and the Moyes Affiliates Amended M Capital II VPF and Cactus VPF — On October 30, 2015, M Capital II and another Moyes Affiliate, Cactus Holding I, entered into the Amended M Capital II VPF and the Cactus VPF, respectively. The purposes of these two VPF contracts were to (i) extend the maturity date of M Capital II's then-existing VPF with Citibank N.A. entered into on October 29, 2013 and maturing on November 4, 2015 through November 6, 2015 and (ii) generate cash proceeds for the repayment of certain stock-secured obligations of Cactus Holding II, a Moyes Affiliate, and thereby effect the release of certain shares of Class B common stock pledged in connection with the same. Cactus Holding I entered into the Cactus VPF contract in respect of 3.3 million shares of the Company's Class B common stock, which were pledged by Cactus Holding I as security for its obligations under the Cactus VPF contract. Under the Cactus VPF contract, Cactus Holding I was required to deliver to Citigroup Global Markets Inc. ("CGMI") a variable amount of stock or cash during a three trading day period at the maturity of the contract on November 21, 2016 through November 24, 2016 (later extended to November 25, 2016, then extended to 2017 as described below). In connection with the Cactus VPF contract, Cactus Holding I received $48.3 million from CGMI (including the $18.5 million noted in the paragraph below). In connection with the Amended M Capital II VPF, M Capital II paid Citibank N.A. $18.5 million . The source of these funds was a cash payment from CGMI in connection with the Cactus VPF Contract. Under the Amended M Capital II VPF contract, M Capital II was required to deliver to Citibank N.A. a variable amount of stock or cash during a three trading day period at the maturity of the contract on November 21, 2016 through November 24, 2016 (later extended to November 25, 2016, then extended to 2017 as described below). The number of shares of the Company's Class B common stock subject to the Amended M Capital II VPF remained unchanged at 13.7 million . On May 18, 2016, M Capital II terminated its VPF covering approximately 12.3 million shares of Class A common stock, and entered into a new VPF covering approximately 12.3 million shares of Class A common stock. The new VPF required M Capital II to deliver a variable amount of Class A common stock, up to a maximum of approximately 12.3 million shares, or an equivalent amount of cash, upon maturity dates occurring on May 26, 2017 through May 31, 2017. The new VPF is collateralized by approximately 12.3 million shares of Class B common stock. Also on May 18, 2016, Cactus Holding I entered into a new VPF covering approximately 7.0 million shares of Class A common stock. The new VPF required Cactus Holding I to deliver a variable amount of Class A common stock, up to a maximum of approximately 7.0 million shares, or an equivalent amount of cash, upon maturity dates occurring on May 26, 2017 through May 31, 2017. The new VPF is collateralized by an aggregate of approximately 7.0 million shares of Class A common stock and Class B common stock which were previously pledged on margin. On November 18, 2016, the maturity dates of the M Capital II VPFs were extended to December 5, 2017 through January 3, 2018, and the maturity dates of the Cactus Holding I VPFs were extended to December 5, 2017 through December 7, 2017. No additional shares were pledged in connection with these extensions. The VPF contracts allow Mr. Moyes and the Moyes Affiliates to retain the same number of shares and voting percentage as they had prior to these VPF contracts. In addition, Mr. Moyes and the Moyes Affiliates are able to participate in price appreciation of the Company's common stock within certain levels. In connection with the VPF transactions described above, an aggregate of approximately 34.3 million shares of Class B common stock and approximately 2.0 million shares of Class A common stock are collateralized to secure M Capital II's and Cactus Holding I's respective obligations under the VPF transactions. Mr. Moyes’ counter party to the VPFs hedges their position by borrowing shares of Class A common stock and subsequently selling such shares, creating a short position. This hedging activity will fluctuate from time to time, based on the current market price of the Class A common stock and the counter party's strategy for reducing risk in their position. This hedging activity may place additional pressure on the price of the Class A common stock as such short positions are being put in place and/or may create a perception that the market is questioning Swift’s performance given the large short position that can occur and be reported. Maintaining this short position may offset some of the risk associated with a full share settlement of the VPF transactions as any shares received by the counter party might be used to settle these short positions thus reducing the amount that would otherwise be introduced to the market. Cactus II Pledging — In July 2011 and December 2011, Cactus Holding Company II, LLC ("Cactus II"), an entity controlled by Mr. Moyes, pledged approximately 12.0 million shares of Class B common stock on margin as collateral for loan arrangements entered into by Cactus II and relating to Mr. Moyes. In connection with these December 2011 transactions, Cactus II converted approximately 6.6 million of the approximately 12.0 million pledged shares of Class B common stock into shares of Class A common stock on a one-for-one basis. During 2012, the Moyes Affiliates converted an additional approximately 1.1 million shares of Class B common stock to Class A common stock and sold approximately 4.8 million of these pledged Class A shares to a counter-party pursuant to a sale and repurchase agreement with a full recourse obligation to repurchase the securities at the same price on the fourth anniversary of sale. This sale and repurchase agreement was replaced in May 2014 with a similar sale and repurchase agreement covering approximately 6.8 million shares. On May 18, 2016 the maturity of this agreement was extended to May 30, 2017, and was extended again on November 18, 2016 to November 30, 2017. On May 18, 2016, 2.0 million shares of Class A common stock and 5.1 million shares of Class B common stock previously pledged on margin for collateral for loan arrangements were transferred to a new VPF agreement as described above. On July 20, 2016, Cactus Holding II pledged an incremental approximately 1.9 million shares as collateral for a new loan arrangement. As of August 2, 2016, the Moyes Affiliates had pledged on margin a total of approximately 4.1 million shares, of which approximately 2.2 million were Class B and approximately 1.9 million were Class A common stock. Other Obligations — On April 20, 2016, Mr. Moyes entered into a settlement agreement with the National Hockey League ("NHL") relating to a previously disclosed lawsuit between the NHL and Mr. Moyes. As part of the settlement agreement, certain of Mr. Moyes’ adult children entered into a Non-Recourse Guaranty and Pledge Agreement with the NHL pursuant to which they guaranteed certain obligations of Mr. Moyes and certain Moyes Affiliates to the NHL. The guarantor’s obligations are collateralized by 2.0 million shares of Class B common stock owned by the guarantors. During 2016 and 2014 , the Moyes Affiliates converted shares of common stock on a one-for-one basis as follows: Transaction Date Converted from Class B Converted to (In thousands) May 4, 2016 (1,250 ) 1,250 May 30, 2014 (1,450 ) 1,450 There were no shares converted in 2015. Stock Plans Compensatory Stock Plans On March 28, 2014, the Board adopted the 2014 Stock Plan, which replaced the 2007 Stock Plan. The 2014 Stock Plan became effective upon stockholder approval on May 8, 2014, after which date no new awards would be granted under the 2007 Stock Plan. The 2007 Stock Plan continues to govern all awards granted under the 2007 Stock Plan until such awards have been exercised, forfeited, canceled, or have otherwise expired or terminated. The 2014 Stock Plan generally contains the same features, terms and conditions as the 2007 Stock Plan. Additionally, the 2014 Stock Plan did not increase the number of shares of stock available for grant, which means that the number of shares available for grant under the 2014 Stock Plan reflected the number of authorized but unissued (and not subject to outstanding awards) under the 2007 Stock Plan as of the date the 2014 Stock Plan became effective. The 2014 Stock Plan permits the payment of cash incentive compensation and authorizes the granting of stock options, stock appreciation rights, restricted stock and RSUs, performance shares and performance units, cash-based awards, and stock-based awards to the Company's employees and non-employee directors for up to 12.0 million shares of Class A common stock. As of December 31, 2016 , the aggregate number of shares remaining available under the 2014 Stock Plan was 4.3 million . Stock-based Compensation Expense Stock-based compensation expense, which is included in "Salaries, wages, and employee benefits" in the consolidated income statements is comprised of the following: Year Ended December 31, 2016 2015 2014 (In thousands) Stock options $ 1,550 $ 1,333 $ 3,007 RSUs and restricted stock 4,467 3,939 1,600 Performance units (1) — 1,253 789 Total stock-based compensation expense $ 6,017 $ 6,525 $ 5,396 Income tax benefit $ 1,841 $ 2,453 $ 1,926 ____________ (1) Targets for the performance units granted in 2014 and 2015 are not expected to be achieved. The following table presents the total unrecognized stock-based compensation expense and the expected weighted average period over which these expenses will be recognized: December 31, 2016 Expense Weighted Average Period (In thousands) (In years) Stock options $ 682 1.35 RSUs and restricted stock $ 7,979 1.31 Performance units $ 478 2.00 Stock Options Stock options are the contingent right of award holders to purchase shares of Swift Transportation Company Class A common stock at a stated price for a limited time. The exercise price of options granted equals the fair value of the Company's common stock determined by the closing price of the Company's Class A common stock quoted on the NYSE on the grant date. All options have a ten -year contractual term. Options granted in 2013 and later have a vesting period of three years at a rate of 33 1/3% per year. Options granted prior to 2013 are fully vested. A summary of the activity related to stock options for the year ended December 31, 2016 follows: Shares Under Option Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (1) (In years) (In thousands) Stock options outstanding at December 31, 2015 3,224,253 $ 11.01 4.04 $ 9,051 Granted 195,999 $ 15.51 Exercised (1,253,152 ) $ 10.56 Expired (11,119 ) $ 13.46 Forfeited (37,818 ) $ 18.87 Stock options outstanding at December 31, 2016 2,118,163 $ 13.42 4.19 $ 23,175 Aggregate number of stock options expected to vest at a future date as of December 31, 2016 234,300 $ 20.93 8.53 $ 803 Exercisable at December 31, 2016 1,849,432 $ 12.32 3.56 $ 22,269 ____________ (1) The aggregate intrinsic value was computed using the closing share price on December 31, 2016 of $24.36 and on December 31, 2015 of $13.82 , as applicable. The fair value of each stock option grant is estimated on the grant date using the Black-Scholes-Merton option-pricing model, which uses a number of assumptions to determine the fair value of the options on the grant date. The following table presents the weighted average assumptions used to determine the fair value of stock options issued: Year Ended December 31, 2016 2015 2014 Dividend yield (1) —% —% —% Risk-free rate of return (2) 1.23% 1.41% 1.28% Expected volatility (3) 40.33% 37.22% 40.00% Expected term (in years) (4) 4.9 5.8 5.8 Weighted average fair value of stock options granted $6.39 $6.96 $6.79 ____________ (1) The dividend yield assumption is based on anticipated dividend payouts. (2) The risk-free interest rate assumption is based on the United States Treasury yield curve at the grant date with maturity dates approximately equal to the expected life at the grant date. (3) The Company estimates the expected volatility and expected option life assumption consistent with ASC Topic 718, Compensation – Stock Compensation . Beginning in 2016, we used our internal historical prices over the expected term of the options to determine our expected volatility. Prior to that, expected volatility was based upon an analysis of historical prices of similar market capitalized trucking group participants within the Dow Jones Total United States Market Index over the expected term of the options. The Company chose a daily measurement interval for historical volatility as it believes this better depicts the nature of employee option exercise decisions being based on shorter-term trends in the price of the underlying shares, rather than on monthly price movements. (4) As a result of the inability to predict the expected future employee exercise behavior, the Company estimated the expected term of the options using a simplified method based on contractual and vesting terms of the options. The Company uses historical data to estimate pre-vesting option forfeitures and records stock-based compensation expense only for those awards that are expected to vest. The following table summarizes stock option exercise information for the years presented: Year Ended December 31, 2016 2015 2014 (In thousands, except share data) Number of stock options exercised 1,253,152 665,531 1,100,998 Intrinsic value of stock options exercised $ 14,266 $ 9,695 $ 15,830 Cash received upon exercise of stock options $ 13,237 $ 6,953 $ 11,488 Income tax benefit $ 2,575 $ 2,147 $ 3,730 The following table is a rollforward of the Company's nonvested stock options: Stock Options Shares Weighted Average Fair Value Nonvested stock options at December 31, 2015 503,740 $ 6.92 Granted 195,999 $ 6.39 Vested (393,190 ) $ 6.09 Forfeited (37,818 ) $ 6.82 Nonvested stock options at December 31, 2016 268,731 $ 6.22 The total fair value of the shares vested during the years ended December 31, 2016 , 2015 , and 2014 was $2.4 million , $3.2 million , and $3.2 million , respectively. Restricted Stock Awards Restricted stock awards are shares of Swift's Class A common stock that are subject to forfeiture until the lapse of defined restrictions, including time-based restrictions. Restricted stock awards, which are granted in the form of restricted stock RSUs and shares, are accounted for as equity awards. Accordingly, the estimated fair value of restricted stock awards is based upon the closing price of the Company's Class A common stock on the grant date. RSU — This is typically the form of restricted stock award granted to Company employees. An RSU represents a right to receive a common share of stock when the unit vests. RSU recipients cannot vote during the vesting period. Employees forfeit their units if their employment terminates before the vesting date. Restricted Stock Share — This is typically the form of restricted stock award granted to the Board. Directors on the Board are entitled to vote during the vesting period. For awards granted in 2014 and thereafter, the forfeiture restrictions associated with restricted stock shares lapse on the first anniversary of the grant date with respect to an equal installment of shares. For awards granted prior to 2014, the forfeiture restrictions associated with restricted stock shares lapsed on each of the first three anniversaries of the grant date with respect to an equal installment of shares. Additionally, restricted stock shares are not transferable for a period of four years from the grant date, other than for applicable tax withholdings. The following table presents restricted stock awards granted under the 2014 Stock Plan: Year Ended December 31, 2016 2015 2014 RSUs granted to company employees 300,150 212,272 203,968 Restricted stock shares granted to the Board 32,235 16,601 17,102 Total restricted stock awards granted 332,385 228,873 221,070 The following table is a rollforward of nonvested restricted stock awards: Restricted Stock Awards Number of Awards Weighted Average Fair Value Nonvested restricted stock awards at December 31, 2015 418,281 $ 22.54 Granted 332,385 $ 15.54 Vested (1) (210,102 ) $ 21.36 Forfeited (27,242 ) $ 21.14 Nonvested restricted stock awards at December 31, 2016 (2) 513,322 $ 18.55 ____________ (1) Includes 19,221 shares of restricted stock previously issued to Board members, and vested during 2016 . (2) Includes 32,235 shares of restricted stock previously issued to Board members, but not yet vested as of December 31, 2016 . Performance Units Beginning in 2013, the Company granted certain members of executive management performance units. These awards provide each grantee a number of shares of Swift's Class A common stock at the end of a three -year period, based on certain performance criteria established by the compensation committee of the Board. The performance criteria are designed to focus management's attention on the Company's key long-term financial goals, and are measured over the three -year period. The following table is a rollforward of nonvested performance units: Performance Units Shares Weighted Average Fair Value Nonvested performance units at December 31, 2015 215,333 $ 18.99 Granted 91,492 $ 15.51 Vested (1) (96,650 ) $ 13.36 Forfeited (5,005 ) $ 24.00 Nonvested performance units at December 31, 2016 205,170 $ 19.97 ____________ (1) The performance period for the performance units granted in May 2014 ended on December 31, 2016 . The Board is not expected to approve the final vesting of these awards subsequent to December 31, 2016 , based on the results of the three -year performance period, but final decision is still pending as of the filing date of this Annual Report on Form 10-K. Non-compensatory Stock Plan: ESPP In 2012, the Company's Board adopted and its stockholders approved the Swift Transportation Company 2012 ESPP. The 2012 ESPP is intended to qualify under Section 423 of the Internal Revenue Code and is considered noncompensatory. Pursuant to the 2012 ESPP, the Company is authorized to issue up to 2.0 million shares of its Class A common stock to eligible employees who participate in the plan. Employees are eligible to participate in the 2012 ESPP following at least 90 days of employment with the Company or any of its participating subsidiaries. Under the terms of the 2012 ESPP, eligible employees may elect to purchase common stock through payroll deductions, not to exceed 15% of their gross cash compensation. The purchase price of the common stock is 95% of the common stock's fair market value quoted on the NYSE on the last trading day of each offering period. There are four three -month offering periods corresponding to the calendar quarters. Each eligible employee is restricted to purchasing a maximum of $6,250 of common stock during an offering period, determined by the fair market value of the common stock as of the first day of the offering period, and $25,000 of common stock during a calendar year. Employees who own 5% or more of the total voting power or value of all classes of common stock are restricted from participating in the 2012 ESPP. During the year ended December 31, 2016 , the Company issued 77,462 shares, under the 2012 ESPP at an average price per share of $17.29 . As of December 31, 2016 , the Company is authorized to issue an additional 1.7 million shares under the 2012 ESPP.

Stock Plans

Stock Plans	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Plans	Common Stock Holders of Class A common stock are entitled to one vote per share , while holders of Class B common stock are entitled to two votes per share on any matter to be voted on by our stockholders. Holders of Class A and Class B common stock vote together as a single class on all matters submitted to a vote of stockholders, unless otherwise required by law, except that a separate vote of each class would be required for: • any merger or consolidation in which holders of shares of Class A common stock receive consideration that is not identical to holders of shares of Class B common stock; • any amendment of Swift Transportation Company's amended and restated certificate of incorporation or amended and restated bylaws that alters the relative rights of its common stockholders; and • any increase in the authorized number of shares of Class B common stock or the issuance of shares of Class B common stock, other than such increase or issuance required to effect a stock split, stock dividend, or recapitalization pro rata with any increase or issuance of Class A common stock. Share Repurchase Programs The following table presents our repurchases of our Class A common stock under the respective share repurchase programs, net of advisory fees: Year Ended December 31, As of December 31, Share Repurchase Program 2016 2015 2016 Authorized Amount Board Approval Date Shares Amount Shares Amount Amount Remaining (In thousands) $100,000 September 24, 2015 2,221 $ 30,000 4,176 $ 70,000 $ — $150,000 February 22, 2016 5,162 $ 87,119 — $ — $ 62,881 7,383 $ 117,119 4,176 $ 70,000 $ 62,881 No share repurchases were made during the year ended December 31, 2014 . Common Stock Transactions — Jerry Moyes and the Moyes Affiliates Amended M Capital II VPF and Cactus VPF — On October 30, 2015, M Capital II and another Moyes Affiliate, Cactus Holding I, entered into the Amended M Capital II VPF and the Cactus VPF, respectively. The purposes of these two VPF contracts were to (i) extend the maturity date of M Capital II's then-existing VPF with Citibank N.A. entered into on October 29, 2013 and maturing on November 4, 2015 through November 6, 2015 and (ii) generate cash proceeds for the repayment of certain stock-secured obligations of Cactus Holding II, a Moyes Affiliate, and thereby effect the release of certain shares of Class B common stock pledged in connection with the same. Cactus Holding I entered into the Cactus VPF contract in respect of 3.3 million shares of the Company's Class B common stock, which were pledged by Cactus Holding I as security for its obligations under the Cactus VPF contract. Under the Cactus VPF contract, Cactus Holding I was required to deliver to Citigroup Global Markets Inc. ("CGMI") a variable amount of stock or cash during a three trading day period at the maturity of the contract on November 21, 2016 through November 24, 2016 (later extended to November 25, 2016, then extended to 2017 as described below). In connection with the Cactus VPF contract, Cactus Holding I received $48.3 million from CGMI (including the $18.5 million noted in the paragraph below). In connection with the Amended M Capital II VPF, M Capital II paid Citibank N.A. $18.5 million . The source of these funds was a cash payment from CGMI in connection with the Cactus VPF Contract. Under the Amended M Capital II VPF contract, M Capital II was required to deliver to Citibank N.A. a variable amount of stock or cash during a three trading day period at the maturity of the contract on November 21, 2016 through November 24, 2016 (later extended to November 25, 2016, then extended to 2017 as described below). The number of shares of the Company's Class B common stock subject to the Amended M Capital II VPF remained unchanged at 13.7 million . On May 18, 2016, M Capital II terminated its VPF covering approximately 12.3 million shares of Class A common stock, and entered into a new VPF covering approximately 12.3 million shares of Class A common stock. The new VPF required M Capital II to deliver a variable amount of Class A common stock, up to a maximum of approximately 12.3 million shares, or an equivalent amount of cash, upon maturity dates occurring on May 26, 2017 through May 31, 2017. The new VPF is collateralized by approximately 12.3 million shares of Class B common stock. Also on May 18, 2016, Cactus Holding I entered into a new VPF covering approximately 7.0 million shares of Class A common stock. The new VPF required Cactus Holding I to deliver a variable amount of Class A common stock, up to a maximum of approximately 7.0 million shares, or an equivalent amount of cash, upon maturity dates occurring on May 26, 2017 through May 31, 2017. The new VPF is collateralized by an aggregate of approximately 7.0 million shares of Class A common stock and Class B common stock which were previously pledged on margin. On November 18, 2016, the maturity dates of the M Capital II VPFs were extended to December 5, 2017 through January 3, 2018, and the maturity dates of the Cactus Holding I VPFs were extended to December 5, 2017 through December 7, 2017. No additional shares were pledged in connection with these extensions. The VPF contracts allow Mr. Moyes and the Moyes Affiliates to retain the same number of shares and voting percentage as they had prior to these VPF contracts. In addition, Mr. Moyes and the Moyes Affiliates are able to participate in price appreciation of the Company's common stock within certain levels. In connection with the VPF transactions described above, an aggregate of approximately 34.3 million shares of Class B common stock and approximately 2.0 million shares of Class A common stock are collateralized to secure M Capital II's and Cactus Holding I's respective obligations under the VPF transactions. Mr. Moyes’ counter party to the VPFs hedges their position by borrowing shares of Class A common stock and subsequently selling such shares, creating a short position. This hedging activity will fluctuate from time to time, based on the current market price of the Class A common stock and the counter party's strategy for reducing risk in their position. This hedging activity may place additional pressure on the price of the Class A common stock as such short positions are being put in place and/or may create a perception that the market is questioning Swift’s performance given the large short position that can occur and be reported. Maintaining this short position may offset some of the risk associated with a full share settlement of the VPF transactions as any shares received by the counter party might be used to settle these short positions thus reducing the amount that would otherwise be introduced to the market. Cactus II Pledging — In July 2011 and December 2011, Cactus Holding Company II, LLC ("Cactus II"), an entity controlled by Mr. Moyes, pledged approximately 12.0 million shares of Class B common stock on margin as collateral for loan arrangements entered into by Cactus II and relating to Mr. Moyes. In connection with these December 2011 transactions, Cactus II converted approximately 6.6 million of the approximately 12.0 million pledged shares of Class B common stock into shares of Class A common stock on a one-for-one basis. During 2012, the Moyes Affiliates converted an additional approximately 1.1 million shares of Class B common stock to Class A common stock and sold approximately 4.8 million of these pledged Class A shares to a counter-party pursuant to a sale and repurchase agreement with a full recourse obligation to repurchase the securities at the same price on the fourth anniversary of sale. This sale and repurchase agreement was replaced in May 2014 with a similar sale and repurchase agreement covering approximately 6.8 million shares. On May 18, 2016 the maturity of this agreement was extended to May 30, 2017, and was extended again on November 18, 2016 to November 30, 2017. On May 18, 2016, 2.0 million shares of Class A common stock and 5.1 million shares of Class B common stock previously pledged on margin for collateral for loan arrangements were transferred to a new VPF agreement as described above. On July 20, 2016, Cactus Holding II pledged an incremental approximately 1.9 million shares as collateral for a new loan arrangement. As of August 2, 2016, the Moyes Affiliates had pledged on margin a total of approximately 4.1 million shares, of which approximately 2.2 million were Class B and approximately 1.9 million were Class A common stock. Other Obligations — On April 20, 2016, Mr. Moyes entered into a settlement agreement with the National Hockey League ("NHL") relating to a previously disclosed lawsuit between the NHL and Mr. Moyes. As part of the settlement agreement, certain of Mr. Moyes’ adult children entered into a Non-Recourse Guaranty and Pledge Agreement with the NHL pursuant to which they guaranteed certain obligations of Mr. Moyes and certain Moyes Affiliates to the NHL. The guarantor’s obligations are collateralized by 2.0 million shares of Class B common stock owned by the guarantors. During 2016 and 2014 , the Moyes Affiliates converted shares of common stock on a one-for-one basis as follows: Transaction Date Converted from Class B Converted to (In thousands) May 4, 2016 (1,250 ) 1,250 May 30, 2014 (1,450 ) 1,450 There were no shares converted in 2015. Stock Plans Compensatory Stock Plans On March 28, 2014, the Board adopted the 2014 Stock Plan, which replaced the 2007 Stock Plan. The 2014 Stock Plan became effective upon stockholder approval on May 8, 2014, after which date no new awards would be granted under the 2007 Stock Plan. The 2007 Stock Plan continues to govern all awards granted under the 2007 Stock Plan until such awards have been exercised, forfeited, canceled, or have otherwise expired or terminated. The 2014 Stock Plan generally contains the same features, terms and conditions as the 2007 Stock Plan. Additionally, the 2014 Stock Plan did not increase the number of shares of stock available for grant, which means that the number of shares available for grant under the 2014 Stock Plan reflected the number of authorized but unissued (and not subject to outstanding awards) under the 2007 Stock Plan as of the date the 2014 Stock Plan became effective. The 2014 Stock Plan permits the payment of cash incentive compensation and authorizes the granting of stock options, stock appreciation rights, restricted stock and RSUs, performance shares and performance units, cash-based awards, and stock-based awards to the Company's employees and non-employee directors for up to 12.0 million shares of Class A common stock. As of December 31, 2016 , the aggregate number of shares remaining available under the 2014 Stock Plan was 4.3 million . Stock-based Compensation Expense Stock-based compensation expense, which is included in "Salaries, wages, and employee benefits" in the consolidated income statements is comprised of the following: Year Ended December 31, 2016 2015 2014 (In thousands) Stock options $ 1,550 $ 1,333 $ 3,007 RSUs and restricted stock 4,467 3,939 1,600 Performance units (1) — 1,253 789 Total stock-based compensation expense $ 6,017 $ 6,525 $ 5,396 Income tax benefit $ 1,841 $ 2,453 $ 1,926 ____________ (1) Targets for the performance units granted in 2014 and 2015 are not expected to be achieved. The following table presents the total unrecognized stock-based compensation expense and the expected weighted average period over which these expenses will be recognized: December 31, 2016 Expense Weighted Average Period (In thousands) (In years) Stock options $ 682 1.35 RSUs and restricted stock $ 7,979 1.31 Performance units $ 478 2.00 Stock Options Stock options are the contingent right of award holders to purchase shares of Swift Transportation Company Class A common stock at a stated price for a limited time. The exercise price of options granted equals the fair value of the Company's common stock determined by the closing price of the Company's Class A common stock quoted on the NYSE on the grant date. All options have a ten -year contractual term. Options granted in 2013 and later have a vesting period of three years at a rate of 33 1/3% per year. Options granted prior to 2013 are fully vested. A summary of the activity related to stock options for the year ended December 31, 2016 follows: Shares Under Option Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (1) (In years) (In thousands) Stock options outstanding at December 31, 2015 3,224,253 $ 11.01 4.04 $ 9,051 Granted 195,999 $ 15.51 Exercised (1,253,152 ) $ 10.56 Expired (11,119 ) $ 13.46 Forfeited (37,818 ) $ 18.87 Stock options outstanding at December 31, 2016 2,118,163 $ 13.42 4.19 $ 23,175 Aggregate number of stock options expected to vest at a future date as of December 31, 2016 234,300 $ 20.93 8.53 $ 803 Exercisable at December 31, 2016 1,849,432 $ 12.32 3.56 $ 22,269 ____________ (1) The aggregate intrinsic value was computed using the closing share price on December 31, 2016 of $24.36 and on December 31, 2015 of $13.82 , as applicable. The fair value of each stock option grant is estimated on the grant date using the Black-Scholes-Merton option-pricing model, which uses a number of assumptions to determine the fair value of the options on the grant date. The following table presents the weighted average assumptions used to determine the fair value of stock options issued: Year Ended December 31, 2016 2015 2014 Dividend yield (1) —% —% —% Risk-free rate of return (2) 1.23% 1.41% 1.28% Expected volatility (3) 40.33% 37.22% 40.00% Expected term (in years) (4) 4.9 5.8 5.8 Weighted average fair value of stock options granted $6.39 $6.96 $6.79 ____________ (1) The dividend yield assumption is based on anticipated dividend payouts. (2) The risk-free interest rate assumption is based on the United States Treasury yield curve at the grant date with maturity dates approximately equal to the expected life at the grant date. (3) The Company estimates the expected volatility and expected option life assumption consistent with ASC Topic 718, Compensation – Stock Compensation . Beginning in 2016, we used our internal historical prices over the expected term of the options to determine our expected volatility. Prior to that, expected volatility was based upon an analysis of historical prices of similar market capitalized trucking group participants within the Dow Jones Total United States Market Index over the expected term of the options. The Company chose a daily measurement interval for historical volatility as it believes this better depicts the nature of employee option exercise decisions being based on shorter-term trends in the price of the underlying shares, rather than on monthly price movements. (4) As a result of the inability to predict the expected future employee exercise behavior, the Company estimated the expected term of the options using a simplified method based on contractual and vesting terms of the options. The Company uses historical data to estimate pre-vesting option forfeitures and records stock-based compensation expense only for those awards that are expected to vest. The following table summarizes stock option exercise information for the years presented: Year Ended December 31, 2016 2015 2014 (In thousands, except share data) Number of stock options exercised 1,253,152 665,531 1,100,998 Intrinsic value of stock options exercised $ 14,266 $ 9,695 $ 15,830 Cash received upon exercise of stock options $ 13,237 $ 6,953 $ 11,488 Income tax benefit $ 2,575 $ 2,147 $ 3,730 The following table is a rollforward of the Company's nonvested stock options: Stock Options Shares Weighted Average Fair Value Nonvested stock options at December 31, 2015 503,740 $ 6.92 Granted 195,999 $ 6.39 Vested (393,190 ) $ 6.09 Forfeited (37,818 ) $ 6.82 Nonvested stock options at December 31, 2016 268,731 $ 6.22 The total fair value of the shares vested during the years ended December 31, 2016 , 2015 , and 2014 was $2.4 million , $3.2 million , and $3.2 million , respectively. Restricted Stock Awards Restricted stock awards are shares of Swift's Class A common stock that are subject to forfeiture until the lapse of defined restrictions, including time-based restrictions. Restricted stock awards, which are granted in the form of restricted stock RSUs and shares, are accounted for as equity awards. Accordingly, the estimated fair value of restricted stock awards is based upon the closing price of the Company's Class A common stock on the grant date. RSU — This is typically the form of restricted stock award granted to Company employees. An RSU represents a right to receive a common share of stock when the unit vests. RSU recipients cannot vote during the vesting period. Employees forfeit their units if their employment terminates before the vesting date. Restricted Stock Share — This is typically the form of restricted stock award granted to the Board. Directors on the Board are entitled to vote during the vesting period. For awards granted in 2014 and thereafter, the forfeiture restrictions associated with restricted stock shares lapse on the first anniversary of the grant date with respect to an equal installment of shares. For awards granted prior to 2014, the forfeiture restrictions associated with restricted stock shares lapsed on each of the first three anniversaries of the grant date with respect to an equal installment of shares. Additionally, restricted stock shares are not transferable for a period of four years from the grant date, other than for applicable tax withholdings. The following table presents restricted stock awards granted under the 2014 Stock Plan: Year Ended December 31, 2016 2015 2014 RSUs granted to company employees 300,150 212,272 203,968 Restricted stock shares granted to the Board 32,235 16,601 17,102 Total restricted stock awards granted 332,385 228,873 221,070 The following table is a rollforward of nonvested restricted stock awards: Restricted Stock Awards Number of Awards Weighted Average Fair Value Nonvested restricted stock awards at December 31, 2015 418,281 $ 22.54 Granted 332,385 $ 15.54 Vested (1) (210,102 ) $ 21.36 Forfeited (27,242 ) $ 21.14 Nonvested restricted stock awards at December 31, 2016 (2) 513,322 $ 18.55 ____________ (1) Includes 19,221 shares of restricted stock previously issued to Board members, and vested during 2016 . (2) Includes 32,235 shares of restricted stock previously issued to Board members, but not yet vested as of December 31, 2016 . Performance Units Beginning in 2013, the Company granted certain members of executive management performance units. These awards provide each grantee a number of shares of Swift's Class A common stock at the end of a three -year period, based on certain performance criteria established by the compensation committee of the Board. The performance criteria are designed to focus management's attention on the Company's key long-term financial goals, and are measured over the three -year period. The following table is a rollforward of nonvested performance units: Performance Units Shares Weighted Average Fair Value Nonvested performance units at December 31, 2015 215,333 $ 18.99 Granted 91,492 $ 15.51 Vested (1) (96,650 ) $ 13.36 Forfeited (5,005 ) $ 24.00 Nonvested performance units at December 31, 2016 205,170 $ 19.97 ____________ (1) The performance period for the performance units granted in May 2014 ended on December 31, 2016 . The Board is not expected to approve the final vesting of these awards subsequent to December 31, 2016 , based on the results of the three -year performance period, but final decision is still pending as of the filing date of this Annual Report on Form 10-K. Non-compensatory Stock Plan: ESPP In 2012, the Company's Board adopted and its stockholders approved the Swift Transportation Company 2012 ESPP. The 2012 ESPP is intended to qualify under Section 423 of the Internal Revenue Code and is considered noncompensatory. Pursuant to the 2012 ESPP, the Company is authorized to issue up to 2.0 million shares of its Class A common stock to eligible employees who participate in the plan. Employees are eligible to participate in the 2012 ESPP following at least 90 days of employment with the Company or any of its participating subsidiaries. Under the terms of the 2012 ESPP, eligible employees may elect to purchase common stock through payroll deductions, not to exceed 15% of their gross cash compensation. The purchase price of the common stock is 95% of the common stock's fair market value quoted on the NYSE on the last trading day of each offering period. There are four three -month offering periods corresponding to the calendar quarters. Each eligible employee is restricted to purchasing a maximum of $6,250 of common stock during an offering period, determined by the fair market value of the common stock as of the first day of the offering period, and $25,000 of common stock during a calendar year. Employees who own 5% or more of the total voting power or value of all classes of common stock are restricted from participating in the 2012 ESPP. During the year ended December 31, 2016 , the Company issued 77,462 shares, under the 2012 ESPP at an average price per share of $17.29 . As of December 31, 2016 , the Company is authorized to issue an additional 1.7 million shares under the 2012 ESPP.

Weighted Average Shares Outstan

Weighted Average Shares Outstanding	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Weighted Average Shares Outstanding	Weighted Average Shares Outstanding Basic and diluted earnings per share, as presented in the consolidated income statements, are calculated by dividing net income by the respective weighted average common shares outstanding during the period. The following table reconciles basic weighted average shares outstanding to diluted weighted average shares outstanding: December 31, 2016 2015 2014 (In thousands) Basic weighted average common shares outstanding 134,139 142,018 141,431 Dilutive effect of stock options 1,355 1,650 2,044 Diluted weighted average common shares outstanding 135,494 143,668 143,475 Anti-dilutive shares excluded from diluted earnings per share (1) 156 354 162 ____________ (1) Shares were excluded from the dilutive-effect calculation because the outstanding options' exercise prices were greater than the average market price of the Company's common shares during the period.

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement ASC Topic 820, Fair Value Measurements and Disclosures, requires that the Company disclose estimated fair values for its financial instruments. The estimated fair value of a financial instrument is the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date in the principal or most advantageous market for the asset or liability. Fair value estimates are made at a specific point in time and are based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the Company's entire holdings of a particular financial instrument. Changes in assumptions could significantly affect these estimates. Because the fair value is estimated as of December 31, 2016 and 2015 , the amounts that will actually be realized or paid at settlement or maturity of the instruments in the future could be significantly different. The tables below exclude certain financial instruments. The excluded financial instruments are as follows: cash and cash equivalents, restricted cash, net accounts receivable, income tax refund receivable, and accounts payable. The estimated fair value of these financial instruments approximate carrying value as they are short-term in nature. Additionally, for notes payable under revolving lines of credit, fair value approximates the carrying value due to the variable interest rate. For capital leases, the carrying value approximates the fair value. The table below also excludes financial instruments reported at estimated fair value on a recurring basis. See "Recurring Fair Value Measurements." All remaining balance sheet amounts excluded from the table below are not considered financial instruments subject to this disclosure. The following table presents the carrying amounts and estimated fair values of the Company's financial instruments: As of December 31, 2016 2015 Carrying Estimated Carrying Estimated (In thousands) Financial Assets: Restricted investments (1) $ 22,717 $ 22,688 $ 23,215 $ 23,190 Financial Liabilities: 2015 Agreement: New Term Loan A, due July 2020 (2) 492,912 494,250 668,055 669,750 Accounts receivable securitization, due January 2019 (3) 279,285 280,000 223,927 225,000 Revolving line of credit, due July 2020 130,000 130,000 200,000 200,000 ____________ The carrying amounts of the final instruments shown in the table are included in the consolidated balance sheets, as follows: (1) Restricted investments are included in "Restricted investments, held to maturity, amortized cost." (2) The New Term Loan A is included in "Current portion of long-term debt" and "Long-term debt, less current portion." Carrying value is net of $1.3 million and $1.7 million DLCs as of December 31, 2016 and 2015, respectively. (3) Carrying value is net of $0.7 million and $1.1 million DLCs as of December 31, 2016 and 2015, respectively. The estimated fair values of the financial instruments shown in the above table as of December 31, 2016 and 2015 , represent management's best estimates of the amounts that would be received to sell those assets or that would be paid to transfer those liabilities in an orderly transaction between market participants at that date. The estimated fair value measurements maximize the use of observable inputs. However, in situations where there is little, if any, market activity for the asset or liability at the measurement date, the estimated fair value measurement reflects the Company's own judgments about the assumptions that market participants would use in pricing the asset or liability. These judgments are developed by the Company based on the best information available under the circumstances. The following summary presents a description of the methods and assumptions used to estimate the fair value of each class of financial instrument. Restricted Investments — The estimated fair value of the Company's restricted investments is based on quoted prices in active markets that are readily and regularly obtainable. Term Loans — The estimated fair value of the Term Loan A approximates the face value. Securitization of Accounts Receivable — The Company's securitization of accounts receivable consists of borrowings outstanding pursuant to the Company's 2015 RSA as of December 31, 2016 and 2015 , as discussed in Note 12 . Its fair value is estimated by discounting future cash flows using a discount rate commensurate with the uncertainty involved. Fair Value Hierarchy — ASC Topic 820 establishes a framework for measuring fair value in accordance with US-GAAP and expands financial statement disclosure requirements for fair value measurements. ASC Topic 820 further specifies a hierarchy of valuation techniques, which is based on whether the inputs into the valuation technique are observable or unobservable. The hierarchy follows: • Level 1 — Valuation techniques in which all significant inputs are quoted prices from active markets for assets or liabilities that are identical to the assets or liabilities being measured. • Level 2 — Valuation techniques in which significant inputs include quoted prices from active markets for assets or liabilities that are similar to the assets or liabilities being measured and/or quoted prices from markets that are not active for assets or liabilities that are identical or similar to the assets or liabilities being measured. Also, model-derived valuations in which all significant inputs and significant value drivers are observable in active markets are Level 2 valuation techniques. • Level 3 — Valuation techniques in which one or more significant inputs or significant value drivers are unobservable. Unobservable inputs are valuation technique inputs that reflect the Company's own assumptions about the assumptions that market participants would use in pricing an asset or liability. When available, the Company uses quoted market prices to determine the estimated fair value of an asset or liability. If quoted market prices are not available, the Company measures fair value using valuation techniques that use, when possible, current market-based or independently-sourced market parameters, such as interest rates and currency rates. The level in the fair value hierarchy within which a fair value measurement in its entirety falls is based on the lowest level input that is significant to the estimated fair value measurement in its entirety. Recurring Fair Value Measurements — As of December 31, 2016 and 2015 , no major categories of assets or liabilities included in the Company's consolidated balance sheets at estimated fair value were measured on a recurring basis. Nonrecurring Fair Value Measurements — As of December 31, 2016 and 2015 there were no liabilities included in the Company's consolidated balance sheets at estimated fair value that were measured on a nonrecurring basis. The following table presents assets measured at estimated fair value on a nonrecurring basis as of December 31, 2016 and 2015 : Fair Value Measurements at Reporting Date Using Estimated Fair Value Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Losses (In thousands) As of December 31, 2016 Software (1) $ — $ — $ — $ — $ (520 ) Equipment (2) 1,963 — — 1,963 (250 ) As of December 31, 2015 Note receivable (3) — — — — (1,480 ) _____________ (1) During the three months ended December 31, 2016, certain operations software related to the Company's logistics business was determined to be fully impaired based on a significant decrease in the expected useful life of the software. This resulted in a pre-tax impairment loss of $0.5 million , which was recorded in "Impairments" within operating income in the consolidated income statement. (2) During the three months ended December 31, 2016, management reassessed the fair value of certain IEL tractors, which had a total book value of $2.2 million , determining that there was a pre-tax impairment loss of $0.3 million . The impairment loss was recorded in "Impairments" within operating income in the consolidated income statement. (3) In September 2013, the Company agreed to advance up to $2.3 million , pursuant to an unsecured promissory note, to an independent fleet contractor that transported freight on Swift's behalf. In March 2015, management became aware that the independent contractor violated various covenants outlined in the unsecured promissory note, which created an event of default that made the principal and accrued interest immediately due and payable. As a result of this event of default, as well as an overall decline in the independent contractor's financial condition, management re-evaluated the fair value of the unsecured promissory note. At March 31, 2015, management determined that the remaining balance due from the independent contractor to the Company was not collectible, which resulted in a $1.5 million pre-tax adjustment that was recorded in "Non-cash impairments of non-operating assets" in the Company's consolidated income statements.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The following table presents Swift's transactions with companies controlled by and/or affiliated with its related parties: Year Ended December 31, 2016 2015 2014 Provided by Swift Received by Swift Provided by Swift Received by Swift Provided by Swift Received by Swift (In thousands) Freight Services: Thermo King (1) $ 1 $ — $ 4 $ — $ — $ — Central Freight Lines (2) 83 26 237 25 25 24 SME Industries (2) 830 — 978 — 185 — Other Affiliates (2) — — — — 14 — Total $ 914 $ 26 $ 1,219 $ 25 $ 224 $ 24 Facility and Equipment Leases: Thermo King (1) $ — $ — $ 12 $ — $ — $ — Central Freight Lines (2) 1,154 372 1,090 435 843 400 Other Affiliates (2) 19 — 20 1 20 228 Total $ 1,173 $ 372 $ 1,122 $ 436 $ 863 $ 628 Other Services: Thermo King (1) $ — $ 633 $ 1 $ 518 $ — $ 184 Central Freight Lines (2) 24 — 142 — 388 — Swift Aircraft Management (2) — 501 — 636 — 699 SME Industries (2) 69 — — — — — Other Affiliates (2) 11 17 1 139 4 73 Total $ 104 $ 1,151 $ 144 $ 1,293 $ 392 $ 956 ____________ (1) Thermo King West, Inc. and Thermo King Chesapeake, Inc. are owned by William Riley III, a member of Swift's Board. Transactions associated with the Thermo King affiliated entities primarily consist of parts and equipment purchases by Swift. Swift also provided freight services, equipment leasing, and other services to the Thermo King affiliated entities. (2) Entities affiliated with majority shareholder, Board member, and (prior to December 31, 2016) Chief Executive Officer, Jerry Moyes include Central Freight Lines, SME Industries, Swift Aircraft Management, Compensi Services, Common Market Trading, LLC, and Southwest Premier Properties. Transactions with these entities that are controlled by and/or are otherwise affiliated with Jerry Moyes, include freight services, facility leases, equipment leases, and other services. • Freight Services Provided by Swift — The rates the Company charges for freight services to each of these companies for transportation services are market rates, which are comparable to rates charged to third-party customers. These transportation services provided to affiliates provide the Company with an additional source of operating revenue at its normal freight rates. • Freight Services Received by Swift — Transportation services received from Central Freight represent LTL freight services rendered to haul parts and equipment to Company shop locations. • Other Services Provided by Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services. • Other Services Received by Swift — Executive air transport, fuel storage, event fees, equipment purchases, miscellaneous repair services, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company. In 2015 , the Company purchased bulk diesel fuel totaling $63 thousand , from Common Market Trading LLC, which is also included in other services received by Swift from other affiliates. Common Market Trading LLC was initially owned by both Jerry Moyes and his brother, Ronald Moyes, but wholly owned by Ronald Moyes as of October 20, 2015. The Company purchased no bulk diesel fuel from Common Market Trading LLC in 2016. Receivables and payables pertaining to these related party transactions were: As of December 31, 2016 2015 Receivable Payable Receivable Payable (In thousands) Thermo King $ — $ 22 $ 4 $ 46 Central Freight Lines 118 1 3 3 SME Industries 72 — 79 — Other Affiliates 3 — 5 29 Total $ 193 $ 23 $ 91 $ 78 See Note 18 for related party transactions pertaining to equity.

Jerry Moyes' Retirement

Jerry Moyes' Retirement	12 Months Ended
	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Jerry Moyes' Retirement	Jerry Moyes' Retirement In conjunction with the Company's September 8, 2016 announcement that Jerry Moyes would retire from his position as Chief Executive Officer effective December 31, 2016, the Company entered into an agreement with Mr. Moyes to memorialize the terms of his retirement. The Company contracted with Mr. Moyes to serve as a non-employee consultant from January 1, 2017 through December 31, 2019 , during which time the Company will pay Mr. Moyes a monthly consulting fee of $0.2 million in cash. Additionally, the Company modified the vesting terms and forfeiture conditions of Mr. Moyes' previously-granted equity awards. As a result of the terms of the agreement, the Company incurred a one-time expense in September 2016 of $7.1 million , consisting of $6.8 million in accrued consulting fees and $0.3 million for the impact of the equity award modifications. The amounts are included in " Salaries, wages, and employee benefits " within the non-reportable segments' income statement. The following is a rollforward of the accrued liability for the consulting fees: (In thousands) Accrued consulting fees – Jerry Moyes, balance at December 31, 2015 $ — Additions to accrual 6,837 Less: payments (162 ) Accrued consulting fees – Jerry Moyes, balance at December 31, 2016 (1) $ 6,675 ____________ (1) The balance is included in "Other liabilities" (noncurrent) and "Accrued liabilities" (current) in the consolidated balance sheet, based on the timing of the expected payment. The $0.3 million impact of the equity award modification is excluded from the accrual balance because it is classified as "Additional paid-in capital" in the consolidated balance sheet.

Information by Segment, Geograp

Information by Segment, Geography, and Customer Concentration	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Information by Segment, Geography, and Customer Concentration	Information by Segment, Geography, and Customer Concentration Segment Information During 2016 , we operated four reportable segments: Truckload, Dedicated, Swift Refrigerated, and Intermodal. Truckload — The truckload segment consists of one-way movements over irregular routes throughout the United States, Mexico, and Canada. This service utilizes both company and owner-operator tractors with dry van, flatbed, and other specialized trailing equipment. Dedicated — Through the dedicated segment, the Company devotes use of equipment to specific customers and offers tailored solutions under long-term contracts. This dedicated segment utilizes refrigerated, dry van, flatbed, and other specialized trailing equipment. Swift Refrigerated — This segment primarily consists of shipments for customers that require temperature-controlled trailers. These shipments include one-way movements over irregular routes, as well as dedicated truck operations. Intermodal — The intermodal segment includes revenue generated by moving freight over the rail in the Company's containers and other trailing equipment, combined with revenue for drayage to transport loads between the railheads and customer locations. Non-reportable Segments — The other non-reportable segments include the Company's logistics and freight brokerage services, as well as support services that its subsidiaries provide to customers and owner-operators, including repair and maintenance shop services, equipment leasing, and insurance. Intangible asset amortization related to the 2007 Transactions, certain legal settlements and reserves, and certain other corporate expenses are also included in the other non-reportable segments. Intersegment Eliminations — Certain operating segments provide transportation and related services for other affiliates outside their reportable segment. Revenues for such services are based on negotiated rates, which we believe approximate fair value, and are reflected as revenues of the billing segment. These rates are adjusted from time to time based on market conditions. Such intersegment revenues and expenses are eliminated in our consolidated results. The following tables present the Company's financial information by segment: Year Ended December 31, 2016 2015 2014 Operating revenue: (In thousands) Truckload $ 2,048,049 $ 2,204,114 $ 2,301,010 Dedicated 971,246 927,657 892,078 Swift Refrigerated 341,280 380,251 417,980 Intermodal 360,157 390,572 401,577 Subtotal 3,720,732 3,902,594 4,012,645 Non-reportable segments 386,349 407,781 342,969 Intersegment eliminations (75,564 ) (81,053 ) (56,890 ) Consolidated operating revenue $ 4,031,517 $ 4,229,322 $ 4,298,724 Year Ended December 31, 2016 2015 2014 Operating income (loss): (In thousands) Truckload $ 181,781 $ 257,007 $ 258,072 Dedicated 108,481 82,735 75,794 Swift Refrigerated (12,844 ) 17,080 14,035 Intermodal (547 ) 4,128 8,298 Subtotal 276,871 360,950 356,199 Non-reportable segments (34,859 ) 9,154 13,871 Consolidated operating income $ 242,012 $ 370,104 $ 370,070 Year Ended December 31, 2016 2015 2014 Depreciation and amortization of property and equipment: (In thousands) Truckload $ 125,611 $ 121,144 $ 113,875 Dedicated 68,090 62,221 53,682 Swift Refrigerated 16,737 16,160 12,510 Intermodal 11,839 13,723 10,875 Subtotal 222,277 213,248 190,942 Non-reportable segments 44,857 38,487 30,180 Consolidated depreciation and amortization of property and equipment $ 267,134 $ 251,735 $ 221,122 Geographical Information In aggregate, operating revenue from the Company's foreign operations was less than 5.0% of consolidated operating revenue for each of the years ended December 31, 2016 , 2015 , and 2014 . Additionally, long-lived assets on the balance sheets of the Company's foreign subsidiaries were less than 5.0% of consolidated "Total assets" as of December 31, 2016 and 2015 . Customer Concentration Services provided to the Company's largest customer, Wal-Mart, generated 14% , 12% , and 11% of operating revenue in 2016 , 2015 , and 2014 , respectively. Operating revenue generated by Wal-Mart is reported in the Truckload, Dedicated, Swift Refrigerated, and Intermodal operating segments. No other customer accounted for 10% or more of operating revenue in the reporting period.

Quarterly Result Of Operations

Quarterly Result Of Operations (Unaudited)	12 Months Ended
	Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]
Quarterly Results of Operations (Unaudited)	Quarterly Results of Operations (Unaudited) In management's opinion, the following summarized financial information fairly presents the Company's results of operations for the quarters noted. These results are not necessarily indicative of future quarterly results. First Quarter Second Quarter Third Quarter Fourth Quarter (In thousands, except per share data) 2016 Operating revenue $ 967,823 $ 1,011,854 $ 1,013,226 $ 1,038,614 Operating income 52,483 74,205 39,853 75,471 Net income 31,905 42,896 24,024 50,442 Basic earnings per share 0.23 0.32 0.18 0.38 Diluted earnings per share 0.23 0.32 0.18 0.38 2015 Operating revenue $ 1,015,144 $ 1,059,404 $ 1,064,973 $ 1,089,801 Operating income 75,000 98,476 74,921 121,707 Net income 37,840 50,954 36,281 72,502 Basic earnings per share 0.27 0.36 0.25 0.52 Diluted earnings per share 0.26 0.35 0.25 0.51

Introduction and Basis of Pre33

Introduction and Basis of Presentation (Policies)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation, Policy [Policy Text Block]	Basis of Presentation The accompanying consolidated financial statements include the accounts of Swift Transportation Company and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in preparing the consolidated financial statements. When the Company does not have a controlling interest in an entity, but exerts significant influence over the entity, the Company applies the equity method of accounting.
Basis of Accounting, Policy [Policy Text Block]	In management's opinion, the accompanying financial statements were prepared in accordance with principles generally accepted in the United States and include all adjustments necessary for the fair presentation of the periods presented.

Summary of Significant Accoun34

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	Use of Estimates — The preparation of the consolidated financial statements, in accordance with US-GAAP, requires management to make estimates and assumptions about future events that affect the amounts reported in the Company's consolidated financial statements and accompanying notes. On an ongoing basis, management evaluates and periodically adjusts its estimates and assumptions, based on historical experience, the impact of the current economic environment, and other key factors. Volatile energy markets, as well as changes in consumer spending have increased the inherent uncertainty in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Significant items subject to such estimates and assumptions include: • carrying amount of property and equipment, intangibles, and goodwill; • valuation allowances for receivables, inventories, and deferred income tax assets; • valuation of financial instruments; • calculation of stock-based compensation; • estimates of claims accruals; • leases, and • contingent obligations.
Segments, Policy [Policy Text Block]	Segments — The Company uses the "management approach" to determine its reportable segments, as well as to determine the basis of reporting the operating segment information. The management approach focuses on financial information that management uses to make operating decisions. Our CODMs use operating revenues, operating expense categories, operating ratios, operating income, and key operating statistics to evaluate performance and allocate resources to the Company's operations. Operating income is the measure that management uses to evaluate segment performance and allocate resources, which is consistent with US-GAAP for segment reporting. Operating income should not be viewed as a substitute for US-GAAP net income (loss). Management believes the presentation of operating income enhances the understanding of the Company's performance by highlighting the results of operations and the underlying profitability drivers of the business segments. Operating income is defined as operating revenues less operating expenses, before income tax expense. Based on the unique nature of the Company's operating structure, revenue-generating assets are interchangeable between segments. Therefore, the Company does not prepare separate balance sheets by segment, as assets are not separately identifiable by segment. The Company allocates depreciation and amortization expense of its property and equipment to the segments based on the actual utilization of the asset by the segment during the period.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents — The Company considers all highly liquid debt instruments purchased with original maturities of three months or less to be cash equivalents. Restricted Cash — The Company's wholly-owned captive insurance companies, Red Rock and Mohave, maintain certain operating bank accounts, working trust accounts, and investment accounts. The cash and short-term investments within the accounts are restricted by insurance regulations to fund the insurance claim losses to be paid by the captive insurance companies. Therefore, these cash and short-term investments are classified as "Cash and cash equivalents – restricted" in the consolidated balance sheets.
Restricted Investments, Policy [Policy Text Block]	Restricted Investments — The Company's investments are restricted by insurance regulations to fund the insurance claim losses to be paid by the captive insurance companies. The Company accounts for its investments in accordance with ASC Topic 320, Investments – Debt and Equity Securities . Management determines the appropriate classification of its investments in debt securities at the time of purchase and re-evaluates the determination on a quarterly basis. As of December 31, 2016 , all of the Company's investments in fixed-maturity securities were classified as held-to-maturity, as the Company has the positive intent and ability to hold these securities to maturity. Held-to-maturity securities are carried at amortized cost. The amortized cost of debt securities is adjusted using the effective interest rate method for amortization of premiums and accretion of discounts. Amortization and accretion is reported in "Other income, net" in the consolidated income statements. Management periodically evaluates restricted investments for impairment. The assessment of whether impairments have occurred is based on management's case-by-case evaluation of the underlying reasons for the decline in estimated fair value. Management accounts for other-than-temporary impairments of debt securities in accordance with ASC Topic 320, Investments – Debt and Equity Securities . This guidance requires the Company to evaluate whether it intends to sell an impaired debt security or whether it is more likely than not that it will be required to sell an impaired debt security before recovery of the amortized cost basis. If either of these criteria are met, an impairment loss equal to the difference between the debt security's amortized cost and its estimated fair value is recognized in earnings. For impaired debt securities that do not meet these criteria, the Company determines if a credit loss exists with respect to the impaired security. If a credit loss exists, the credit loss component of the impairment (i.e., the difference between the security's amortized cost and the present value of projected future cash flows expected to be collected) is recognized in earnings and the remaining portion of the impairment is recognized as a component of AOCI.
Inventories and Supplies, Policy [Policy Text Block]	Inventories and Supplies — Inventories and supplies primarily consist of spare parts, tires, fuel, and supplies and are stated at lower of cost or market. Cost is determined using the first-in, first-out method.
Property and Equipment, Policy [Policy Text Block]	Property and Equipment — Property and equipment are stated at cost. Costs to construct significant assets include capitalized interest incurred during the construction and development period. Expenditures for replacements and improvements are capitalized. Maintenance and repairs are expensed as incurred. Depreciation of property and equipment is calculated on a straight-line basis over the following estimated useful lives: Category Range Facilities and improvements 3 to 40 years Revenue and service equipment 2 to 20 years Furniture and office equipment 3 to 5 years Net gains on the disposal of property and equipment are presented in the consolidated income statements within operating income. Tires on purchased revenue equipment are capitalized along with the related equipment cost when the vehicle is placed in service and depreciated over the life of the vehicle. Replacement tires are classified as inventory and expensed when placed in service. Management evaluates its property and equipment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable in accordance with ASC Topic 360, Property, Plant and Equipment . When such events or changes in circumstances occur, management performs a recoverability test that compares the carrying amount with the projected undiscounted cash flows from the use and eventual disposition of the asset or asset group. An impairment is recorded for any excess of the carrying amount over the estimated fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary.
Intangible Assets other than Goodwill, Policy [Policy Text Block]	Intangible Assets other than Goodwill — The Company's intangible assets other than goodwill primarily consist of acquired customer relationships and trade names. Amortization of acquired customer relationships is calculated on the 150% declining balance method over the estimated useful life of 15 years . The customer relationship contributed to the Company at May 9, 2007 is amortized over 15 years on a straight-line basis. The trade name has an indefinite useful life and is not amortized, but is tested for impairment at least annually, unless events occur or circumstances change between annual tests that would more likely than not reduce the fair value. Management reviews its intangible assets for impairment whenever events or circumstances indicate that the carrying amount of the asset may not be recoverable, in accordance with ASC Topic 350, Intangibles – Goodwill and Other. When such events or changes in circumstances occur, management performs a recoverability test that compares the carrying amount with the projected undiscounted cash flows from the use and eventual disposition of the asset or asset group. An impairment is recorded for any excess of the carrying amount over the estimated fair value, which is generally determined using discounted future cash flows.
Goodwill, Policy [Policy Text Block]	Goodwill — Management evaluates goodwill on an annual basis as of November 30 th , or more frequently if indicators of impairment exist. The Company assesses qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than the carrying amount. If the Company concludes that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, the Company conducts a two -step quantitative goodwill impairment test. The first step of the quantitative impairment test involves comparing the fair values of the applicable reporting units with their carrying values. Management estimates the fair values of its reporting units using a combination of the income and market approaches. If the carrying amount of a reporting unit exceeds the reporting unit's fair value, then management performs the second step of the quantitative impairment test. The second step of the quantitative impairment test involves comparing the implied fair value of the affected reporting unit's goodwill with the carrying value of that goodwill. Any amount by which the carrying value of the goodwill exceeds its implied fair value is recognized as an impairment loss. Refer to Note 8 for discussion of the results of the Company's annual evaluation as of November 30, 2016 .
Claims Accruals, Policy [Policy Text Block]	Claims Accruals — The Company is self-insured for a portion of its risk related to auto liability, workers' compensation, property damage, and cargo damage. Prior to January 1, 2015, the Company was also self-insured for a portion of its employer medical expense. Self-insurance results from buying insurance coverage that applies in excess of a retained portion of risk for each respective line of coverage. The Company accrues for the cost of the uninsured portion of pending claims by evaluating the nature and severity of individual claims and by estimating future claims development based upon historical claims development trends. The actual cost to settle self-insured claim liabilities may differ from our reserve estimates due to legal costs, claims that have been incurred but not reported and various other uncertainties, including the inherent difficulty in estimating the severity of the claims and the potential judgment or settlement amount to dispose of the claim.
Fair Value Measurement, Policy [Policy Text Block]	The estimated fair values of the financial instruments shown in the above table as of December 31, 2016 and 2015 , represent management's best estimates of the amounts that would be received to sell those assets or that would be paid to transfer those liabilities in an orderly transaction between market participants at that date. The estimated fair value measurements maximize the use of observable inputs. However, in situations where there is little, if any, market activity for the asset or liability at the measurement date, the estimated fair value measurement reflects the Company's own judgments about the assumptions that market participants would use in pricing the asset or liability. These judgments are developed by the Company based on the best information available under the circumstances. The following summary presents a description of the methods and assumptions used to estimate the fair value of each class of financial instrument. Restricted Investments — The estimated fair value of the Company's restricted investments is based on quoted prices in active markets that are readily and regularly obtainable. Term Loans — The estimated fair value of the Term Loan A approximates the face value. Securitization of Accounts Receivable — The Company's securitization of accounts receivable consists of borrowings outstanding pursuant to the Company's 2015 RSA as of December 31, 2016 and 2015 , as discussed in Note 12 . Its fair value is estimated by discounting future cash flows using a discount rate commensurate with the uncertainty involved. Fair Value Hierarchy — ASC Topic 820 establishes a framework for measuring fair value in accordance with US-GAAP and expands financial statement disclosure requirements for fair value measurements. ASC Topic 820 further specifies a hierarchy of valuation techniques, which is based on whether the inputs into the valuation technique are observable or unobservable. The hierarchy follows: • Level 1 — Valuation techniques in which all significant inputs are quoted prices from active markets for assets or liabilities that are identical to the assets or liabilities being measured. • Level 2 — Valuation techniques in which significant inputs include quoted prices from active markets for assets or liabilities that are similar to the assets or liabilities being measured and/or quoted prices from markets that are not active for assets or liabilities that are identical or similar to the assets or liabilities being measured. Also, model-derived valuations in which all significant inputs and significant value drivers are observable in active markets are Level 2 valuation techniques. • Level 3 — Valuation techniques in which one or more significant inputs or significant value drivers are unobservable. Unobservable inputs are valuation technique inputs that reflect the Company's own assumptions about the assumptions that market participants would use in pricing an asset or liability. When available, the Company uses quoted market prices to determine the estimated fair value of an asset or liability. If quoted market prices are not available, the Company measures fair value using valuation techniques that use, when possible, current market-based or independently-sourced market parameters, such as interest rates and currency rates. The level in the fair value hierarchy within which a fair value measurement in its entirety falls is based on the lowest level input that is significant to the estimated fair value measurement in its entirety.
Contingencies, Policy [Policy Text Block]	The Company is involved in certain claims and pending litigation primarily arising in the normal course of business. The majority of these claims relate to workers' compensation, auto collision and liability, physical damage, and cargo damage. The Company accrues for the uninsured portion of claims losses and the gross amount of other losses when the likelihood of the loss is probable and the amount of the loss is reasonably estimable. These accruals are based on management's best estimate within a possible range of loss. When there is no amount within the range of loss that appears to be a better estimate than any other amount, then management accrues to the low end of the range. Legal fees are expensed as incurred. When it is reasonably possible that exposure exists in excess of the related accrual (which could be no accrual), management discloses an estimate of the possible loss or range of loss, unless an estimate cannot be determined. If the likelihood of a loss is remote, the Company does not accrue for the loss. However if the likelihood of a loss is remote, but it is at least reasonably possible that one or more future confirming events may materially change management's estimate within twelve months from the date of the financial statements, management discloses an estimate of the possible loss or range of loss, unless an estimate cannot be determined.
Revenue Recognition, Policy [Policy Text Block]	Revenue Recognition — The Company recognizes operating revenues and the related direct costs of such revenue as of the date the freight is delivered, in accordance with ASC Topic 605-20-25-13, Services for Freight-in-Transit at the End of a Reporting Period. The Company recognizes operating lease revenue from leasing tractors and related equipment to owner-operators. Operating lease revenue from rental operations is recognized as earned, which is straight-lined per the rent schedules in the lease agreements. Losses from lease defaults are recognized as offsets to revenue.
Stock-based Compensation, Policy [Policy Text Block]	Stock-based Compensation — The Company accounts for stock-based compensation expense in accordance with ASC Topic 718, Compensation – Stock Compensation. ASC Topic 718 requires that all share-based payments to employees and non-employee directors, including grants of employee stock options, be recognized in the financial statements based upon a grant-date fair value of an award. The Company calculates the number of awards expected to vest as awards granted, less expected forfeitures over the life of the award (estimated at grant date). Compensation expense is recorded based on amortization of the grant-date fair value over a graded vesting period. Unless a material deviation from the assumed forfeiture rate is observed during the term in which the awards are expensed, any adjustment necessary to reflect differences in actual experience is recognized in the period the award becomes payable or exercisable. See Note 19 for additional information relating to the Company's stock compensation plan.
Income Taxes, Policy [Policy Text Block]	Income Taxes — Management accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to operating loss and tax credit carryforwards, as well as differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Net deferred incomes taxes are classified as noncurrent in the consolidated balance sheets. The effect on deferred tax assets and liabilities of changes in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is provided against deferred tax assets if the Company determines it is more likely than not that such assets will not ultimately be realized. The Company does not recognize a tax benefit for uncertain tax positions unless it concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that, in the management's judgment, is greater than 50% likely to be realized. The Company records expected incurred interest and penalties related to unrecognized tax positions in "Income tax expense" in the consolidated income statements. To the extent that such interest and penalties are not ultimately incurred, previously accrued amounts are reduced and reflected as a reduction of the income tax provision.

Introduction and Basis of Pre35

Introduction and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The Company retrospectively adjusted the December 31, 2015 consolidated balance sheet to align with the current period presentation, as follows: December 31, 2015 Financial Statement Caption Unadjusted Consolidated Balance Sheet Reclassification Adjustments Adjusted Consolidated Balance Sheet (In thousands) ASSETS: Other assets $ 29,353 $ (2,768 ) $ 26,585 LIABILITIES: Current portion of long-term debt $ 35,582 $ (68 ) $ 35,514 Long-term debt, less current portion 645,290 (1,627 ) 643,663 Accounts receivable securitization 225,000 (1,073 ) 223,927 Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact January 2017 2017-04: Intangibles – Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment The amendments in this ASU are intended to simplify subsequent measurement of goodwill. The key amendment in the ASU eliminates Step 2 from the goodwill impairment test, in which entities measured a goodwill impairment loss by comparing the implied fair value to the carrying amount of a reporting unit's goodwill. Instead, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value with the carrying amount of a reporting unit and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value. January 2020, prospective Currently under evaluation; not expected to be material January 2017 2017-03: Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323) – Amendments to SEC Paragraphs Pursuant to Staff Announcements at the September 22, 2016 and November 17, 2016 EITF Meetings The amendments in this ASU that are relevant to the Company pertain to disclosures around the impact that recently issued accounting standards will have on the financial statements of a registrant when such standards are adopted in a future period. The amendments in this ASU indicate that the SEC staff expects that if an entity cannot reasonably estimate the impact of an ASU on the financial statements, then the entity should consider additional qualitative disclosures to assist the reader in assessing the significance of the standard's impact on its financial statements. Immediate None - The Company's policy on disclosing recently issued accounting pronouncements is aligned with the amendments in this ASU. November 2016 2016-18: S tatement of Cash Flows – (Topic 230) Restricted Cash (a Consensus of the FASB Emerging Issues Task Force) The amendments in this ASU require transfers between cash and equivalents and restricted cash and equivalents, as well as direct cash receipts into and cash payments made from restricted cash and equivalents to be explained in the statement of cash flows. Restricted cash and restricted cash equivalents are to be included in the beginning and ending cash and cash equivalent balance totals on the statement of cash flows. January 2018; Retrospective Material impact in cash flow presentation to reclassify restricted cash to "net increase/decrease in cash, restricted cash, and equivalents," and adjust the beginning and ending balances. October 2016 2016-17: Consolidation (Topic 810) – Interests Held through Related Parties that are under Common Control This ASU updates the consolidation guidance on how a reporting entity that is a single decision maker of a Variable Interest Entity ('VIE") should treat indirect interests in the entity held through related parties that are under common control when determining whether it is the primary beneficiary of the VIE. The primary beneficiary of a VIE is the reporting entity that has a controlling financial interest in a VIE and, therefore, consolidates the VIE. A reporting entity that has an indirect interest in a VIE if it has a direct interest in a related party that, in turn has a direct interest in the VIE. January 2017, Modified Retrospective No financial statement impact. The Company is not the primary beneficiary of any of its related parties. Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact October 2016 2016-16: Income Taxes (Topic 740) – Intra-entity Transfers of Assets Other than Inventory This ASU states that entities should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs (as compared to current GAAP, which prohibits the recognition of current and deferred income taxes for intra-entity asset transfer until the asset has been sold to an outside party). January 2018, Modified Retrospective Currently under evaluation; not expected to be material since the Company's fixed assets are not typically transferred between legal entities for consideration. August 2016 2016-15: Statement of Cash Flows (Topic 230) – Classification of Certain Cash Receipts and Cash Payments This ASU has several amendments, which are designed to reduce existing diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The ASU addresses eight specific cash flow issues, of which the following are expected to be applicable to Swift: 1) debt prepayment and extinguishment costs, 2) proceeds from settlement of insurance claims, 3) proceeds from settlement of corporate-owned life insurance policies, 4) beneficial interests in securitization transactions, and 5) separately identifiable cash flows and application of the predominance principle. January 2018, Retrospective Currently under evaluation; not expected to be material. June 2016 2016-13: Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments The purpose of this ASU is to amend the current incurred loss impairment methodology with a new methodology that reflects expected credit losses and requires a broader range of reasonable and supportable information to inform credit loss estimates. This is the final credit accounting standard, out of a series, with detailed guidance on the new loss reserve model, Current Expected Credit Loss ("CECL"). Among other provisions, the amendments in the ASU require a financial asset (or group of assets) measured at amortized cost basis to be presented at the net amount expected to be collected. Entities are no longer required to wait until a loss is probable to record it. January 2020, Adoption method varies by amendment Currently under evaluation; not expected to be material. May 2016 2016-12: Revenue from Contracts with Customers (Topic 606) – Narrow-scope Improvements and Practical Expedients The amendments in this ASU clarify certain aspects regarding the collectibility criterion, sales taxes collected from customers, noncash consideration, contract modifications, and completed contracts at transition. It additionally clarifies that retrospective application only requires disclosure of the accounting change effect on prior periods presented, not on the period of adoption. January 2018, Modified retrospective Currently under evaluation (1) April 2016 2016-10: Revenue from Contracts with Customers (Topic 606) – Identifying Performance Obligations and Licensing The amendments in this ASU clarify the following two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance, while retaining the related principles for those areas. The amendments do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) March 2016 2016-08: Revenue from Contracts with Customers (Topic 606) – Principal versus Agent Considerations (Reporting Revenue Gross versus Net) The amendments in this ASU are intended to improve the operability and understandability of the implementation guidance on principal versus agent considerations, but do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact March 2016 2016-09: Compensation – Stock Compensation (Topic 718) – Improvements to Employee Share-based Payment Accounting The amendments in this ASU are intended to simplify various aspects of accounting for stock-based compensation, including income tax consequences, classification of awards as equity or liability, as well as classification of activities within the statement of cash flows. January 2017, Adoption method varies by amendment Expected to be material (2) February 2016 2016-02: Leases (Topic 842) The new standard requires lessees to recognize assets and liabilities arising from both operating and financing leases on the balance sheet. Lessor accounting for leases is largely unaffected by the new guidance. January 2019, Modified retrospective Currently under evaluation; expected to be material, but not yet quantifiable. January 2016 2016-01: Financial Instruments – Overall (Subtopic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities The amendments in this ASU address various aspects of recognition, measurement, presentation, and disclosure of financial instruments. They additionally establish ASC Topic 321 – Investments – Equity Securities , which applies to investments in equity securities and other ownership interests in an entity, including investments in partnerships, unincorporated joint ventures, and limited liability companies. January 2018, Modified retrospective Not expected to be material. August 2015 2015-14: Revenue from Contracts with Customers (Topic 606) – Deferral of the Effective Date This ASU deferred the effective date of ASU 2014-09 (Topic 606) to annual reporting periods beginning after December 15, 2017. January 2018, Modified retrospective Currently under evaluation (1) July 2015 2015-11: Inventory (Topic 330) – Simplifying the Measurement of Inventory The amendments in this ASU simplify subsequent measurement of inventory for all inventory measurement methods, except for last-in-first-out. Entities will be required to measure inventory at the lower of cost and net realizable value, instead of the previously issued guidance of lower of cost or market. January 2017, prospective Not expected to be material. Due to the nature of the Company's inventory balances (spare parts, tires, fuel, and supplies), inventory is predominantly stated at cost. ____________ (1) Management is in the diagnostic phase of assessing the financial and business impacts of implementing ASC Topic 606, Revenue from Contracts with Customers , including identifying revenue sources within the Company's lines of business, reviewing a sample of contracts, and developing a preliminary assessment. Based upon these preliminary procedures, management anticipates that the following key considerations will impact the Company's accounting and reporting under the new standard: • identification of what constitutes a contract in Swift's business practices, • variability in individual contracts, such as customer-specific terms that may vary from the master agreement, • principal versus agent determinations, • timing of revenue recognition (for example, point-in-time versus over time and/or accelerated versus deferred), • single versus multiple performance obligations, • new/changed estimates and management judgments (for example, system estimation of in-transit accruals versus manual estimation), • disaggregation of revenue by category within segments, and • others. Management expects that there will also be changes in sales, contracting, accounting, reporting, tax, debt covenants, and other business processes, policies, and controls, as a result of implementing ASC Topic 606. The Company is currently underway with implementing a new ERP system, which will also affect the implementation process. Based on the information currently available from the diagnostic phase, management cannot yet determine the quantitative impact on the financial statements; however, the impact is expected to be immaterial (potentially with changes only to the timing of revenue recognition between reportable periods, as well as changes in the requirements for accounting policy and other new disclosures). The financial impact is expected to be quantifiable by the time the Company files its first Quarterly Report on Form 10-Q in 2017, at which time the Company will be transitioning into the design and planning phase of implementing ASC Topic 606. Since we are continuing to evaluate the impact of ASC Topic 606, our disclosures around our preliminary assessments are subject to change. (2) The amendments to ASC Topic 718, Compensation – Stock Compensation , that are expected to affect the Company are discussed below. • Accounting for Income Tax Benefits/Deficiencies : All excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) should be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity should also recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company will need to reclassify approximately $16.8 million in historical net tax benefit/deficiency amounts previously recorded within additional paid-in capital into retained earnings/accumulated deficit. Going forward, tax benefit/deficiency amounts will be recorded in net income. • Classification of Excess Tax Benefits on the Statement of Cash Flows : Excess tax benefits should be classified along with other income tax cash flows as an operating activity. Application is permitted to be prospective or retrospective. Current GAAP requires classification within cash flows from financing activities. The Company presents its statement of cash flows using the indirect method, which presents excess tax benefits within cash flows from financing activities and a corresponding offset within the net income reconciliation of cash flows from operating activities. As such, the Company will need to reclassify the excess tax benefit amounts out of cash flows from financing activities and into cash flows from operating activities, upon adoption. Management expects to apply these amendments retrospectively. • Forfeitures : An entity can make an entity-wide accounting policy election to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures when they occur. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company expects to transition to accounting for forfeitures when they occur. This would result in approximately a $2.5 million unfavorable cumulative-effect adjustment to retained earnings/accumulated deficit to catch-up the previously unrecognized stock-based compensation associated with historical assumed forfeiture rates. Going forward, forfeitures will be recorded as favorable adjustments to stock-based compensation as they occur. • Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-withholding purposes : Cash paid by an employer when directly withholding shares for tax-withholding purposes should be classified as a financing activity. Retrospective application is required. Beginning in 2016, the Company began allowing certain members of management to have shares withheld for taxes when their restricted stock awards and performance units vest. As such, upon adopting the amendments in this ASU, the Company will need to present the amounts out of cash flows from operating activities and into cash flows from financing activities for the periods presented. For 2016, the amount was approximately $0.5 million .

Summary of Significant Accoun36

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment [Table Text Block]	Depreciation of property and equipment is calculated on a straight-line basis over the following estimated useful lives: Category Range Facilities and improvements 3 to 40 years Revenue and service equipment 2 to 20 years Furniture and office equipment 3 to 5 years

Recently Issued Accounting Pr37

Recently Issued Accounting Pronouncements (Tables)	12 Months Ended
	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The Company retrospectively adjusted the December 31, 2015 consolidated balance sheet to align with the current period presentation, as follows: December 31, 2015 Financial Statement Caption Unadjusted Consolidated Balance Sheet Reclassification Adjustments Adjusted Consolidated Balance Sheet (In thousands) ASSETS: Other assets $ 29,353 $ (2,768 ) $ 26,585 LIABILITIES: Current portion of long-term debt $ 35,582 $ (68 ) $ 35,514 Long-term debt, less current portion 645,290 (1,627 ) 643,663 Accounts receivable securitization 225,000 (1,073 ) 223,927 Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact January 2017 2017-04: Intangibles – Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment The amendments in this ASU are intended to simplify subsequent measurement of goodwill. The key amendment in the ASU eliminates Step 2 from the goodwill impairment test, in which entities measured a goodwill impairment loss by comparing the implied fair value to the carrying amount of a reporting unit's goodwill. Instead, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value with the carrying amount of a reporting unit and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value. January 2020, prospective Currently under evaluation; not expected to be material January 2017 2017-03: Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323) – Amendments to SEC Paragraphs Pursuant to Staff Announcements at the September 22, 2016 and November 17, 2016 EITF Meetings The amendments in this ASU that are relevant to the Company pertain to disclosures around the impact that recently issued accounting standards will have on the financial statements of a registrant when such standards are adopted in a future period. The amendments in this ASU indicate that the SEC staff expects that if an entity cannot reasonably estimate the impact of an ASU on the financial statements, then the entity should consider additional qualitative disclosures to assist the reader in assessing the significance of the standard's impact on its financial statements. Immediate None - The Company's policy on disclosing recently issued accounting pronouncements is aligned with the amendments in this ASU. November 2016 2016-18: S tatement of Cash Flows – (Topic 230) Restricted Cash (a Consensus of the FASB Emerging Issues Task Force) The amendments in this ASU require transfers between cash and equivalents and restricted cash and equivalents, as well as direct cash receipts into and cash payments made from restricted cash and equivalents to be explained in the statement of cash flows. Restricted cash and restricted cash equivalents are to be included in the beginning and ending cash and cash equivalent balance totals on the statement of cash flows. January 2018; Retrospective Material impact in cash flow presentation to reclassify restricted cash to "net increase/decrease in cash, restricted cash, and equivalents," and adjust the beginning and ending balances. October 2016 2016-17: Consolidation (Topic 810) – Interests Held through Related Parties that are under Common Control This ASU updates the consolidation guidance on how a reporting entity that is a single decision maker of a Variable Interest Entity ('VIE") should treat indirect interests in the entity held through related parties that are under common control when determining whether it is the primary beneficiary of the VIE. The primary beneficiary of a VIE is the reporting entity that has a controlling financial interest in a VIE and, therefore, consolidates the VIE. A reporting entity that has an indirect interest in a VIE if it has a direct interest in a related party that, in turn has a direct interest in the VIE. January 2017, Modified Retrospective No financial statement impact. The Company is not the primary beneficiary of any of its related parties. Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact October 2016 2016-16: Income Taxes (Topic 740) – Intra-entity Transfers of Assets Other than Inventory This ASU states that entities should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs (as compared to current GAAP, which prohibits the recognition of current and deferred income taxes for intra-entity asset transfer until the asset has been sold to an outside party). January 2018, Modified Retrospective Currently under evaluation; not expected to be material since the Company's fixed assets are not typically transferred between legal entities for consideration. August 2016 2016-15: Statement of Cash Flows (Topic 230) – Classification of Certain Cash Receipts and Cash Payments This ASU has several amendments, which are designed to reduce existing diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The ASU addresses eight specific cash flow issues, of which the following are expected to be applicable to Swift: 1) debt prepayment and extinguishment costs, 2) proceeds from settlement of insurance claims, 3) proceeds from settlement of corporate-owned life insurance policies, 4) beneficial interests in securitization transactions, and 5) separately identifiable cash flows and application of the predominance principle. January 2018, Retrospective Currently under evaluation; not expected to be material. June 2016 2016-13: Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments The purpose of this ASU is to amend the current incurred loss impairment methodology with a new methodology that reflects expected credit losses and requires a broader range of reasonable and supportable information to inform credit loss estimates. This is the final credit accounting standard, out of a series, with detailed guidance on the new loss reserve model, Current Expected Credit Loss ("CECL"). Among other provisions, the amendments in the ASU require a financial asset (or group of assets) measured at amortized cost basis to be presented at the net amount expected to be collected. Entities are no longer required to wait until a loss is probable to record it. January 2020, Adoption method varies by amendment Currently under evaluation; not expected to be material. May 2016 2016-12: Revenue from Contracts with Customers (Topic 606) – Narrow-scope Improvements and Practical Expedients The amendments in this ASU clarify certain aspects regarding the collectibility criterion, sales taxes collected from customers, noncash consideration, contract modifications, and completed contracts at transition. It additionally clarifies that retrospective application only requires disclosure of the accounting change effect on prior periods presented, not on the period of adoption. January 2018, Modified retrospective Currently under evaluation (1) April 2016 2016-10: Revenue from Contracts with Customers (Topic 606) – Identifying Performance Obligations and Licensing The amendments in this ASU clarify the following two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance, while retaining the related principles for those areas. The amendments do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) March 2016 2016-08: Revenue from Contracts with Customers (Topic 606) – Principal versus Agent Considerations (Reporting Revenue Gross versus Net) The amendments in this ASU are intended to improve the operability and understandability of the implementation guidance on principal versus agent considerations, but do not change the core principle of the guidance. January 2018, Modified retrospective Currently under evaluation (1) Date Issued Reference Description Expected Adoption Date and Method Financial Statement Impact March 2016 2016-09: Compensation – Stock Compensation (Topic 718) – Improvements to Employee Share-based Payment Accounting The amendments in this ASU are intended to simplify various aspects of accounting for stock-based compensation, including income tax consequences, classification of awards as equity or liability, as well as classification of activities within the statement of cash flows. January 2017, Adoption method varies by amendment Expected to be material (2) February 2016 2016-02: Leases (Topic 842) The new standard requires lessees to recognize assets and liabilities arising from both operating and financing leases on the balance sheet. Lessor accounting for leases is largely unaffected by the new guidance. January 2019, Modified retrospective Currently under evaluation; expected to be material, but not yet quantifiable. January 2016 2016-01: Financial Instruments – Overall (Subtopic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities The amendments in this ASU address various aspects of recognition, measurement, presentation, and disclosure of financial instruments. They additionally establish ASC Topic 321 – Investments – Equity Securities , which applies to investments in equity securities and other ownership interests in an entity, including investments in partnerships, unincorporated joint ventures, and limited liability companies. January 2018, Modified retrospective Not expected to be material. August 2015 2015-14: Revenue from Contracts with Customers (Topic 606) – Deferral of the Effective Date This ASU deferred the effective date of ASU 2014-09 (Topic 606) to annual reporting periods beginning after December 15, 2017. January 2018, Modified retrospective Currently under evaluation (1) July 2015 2015-11: Inventory (Topic 330) – Simplifying the Measurement of Inventory The amendments in this ASU simplify subsequent measurement of inventory for all inventory measurement methods, except for last-in-first-out. Entities will be required to measure inventory at the lower of cost and net realizable value, instead of the previously issued guidance of lower of cost or market. January 2017, prospective Not expected to be material. Due to the nature of the Company's inventory balances (spare parts, tires, fuel, and supplies), inventory is predominantly stated at cost. ____________ (1) Management is in the diagnostic phase of assessing the financial and business impacts of implementing ASC Topic 606, Revenue from Contracts with Customers , including identifying revenue sources within the Company's lines of business, reviewing a sample of contracts, and developing a preliminary assessment. Based upon these preliminary procedures, management anticipates that the following key considerations will impact the Company's accounting and reporting under the new standard: • identification of what constitutes a contract in Swift's business practices, • variability in individual contracts, such as customer-specific terms that may vary from the master agreement, • principal versus agent determinations, • timing of revenue recognition (for example, point-in-time versus over time and/or accelerated versus deferred), • single versus multiple performance obligations, • new/changed estimates and management judgments (for example, system estimation of in-transit accruals versus manual estimation), • disaggregation of revenue by category within segments, and • others. Management expects that there will also be changes in sales, contracting, accounting, reporting, tax, debt covenants, and other business processes, policies, and controls, as a result of implementing ASC Topic 606. The Company is currently underway with implementing a new ERP system, which will also affect the implementation process. Based on the information currently available from the diagnostic phase, management cannot yet determine the quantitative impact on the financial statements; however, the impact is expected to be immaterial (potentially with changes only to the timing of revenue recognition between reportable periods, as well as changes in the requirements for accounting policy and other new disclosures). The financial impact is expected to be quantifiable by the time the Company files its first Quarterly Report on Form 10-Q in 2017, at which time the Company will be transitioning into the design and planning phase of implementing ASC Topic 606. Since we are continuing to evaluate the impact of ASC Topic 606, our disclosures around our preliminary assessments are subject to change. (2) The amendments to ASC Topic 718, Compensation – Stock Compensation , that are expected to affect the Company are discussed below. • Accounting for Income Tax Benefits/Deficiencies : All excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) should be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity should also recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company will need to reclassify approximately $16.8 million in historical net tax benefit/deficiency amounts previously recorded within additional paid-in capital into retained earnings/accumulated deficit. Going forward, tax benefit/deficiency amounts will be recorded in net income. • Classification of Excess Tax Benefits on the Statement of Cash Flows : Excess tax benefits should be classified along with other income tax cash flows as an operating activity. Application is permitted to be prospective or retrospective. Current GAAP requires classification within cash flows from financing activities. The Company presents its statement of cash flows using the indirect method, which presents excess tax benefits within cash flows from financing activities and a corresponding offset within the net income reconciliation of cash flows from operating activities. As such, the Company will need to reclassify the excess tax benefit amounts out of cash flows from financing activities and into cash flows from operating activities, upon adoption. Management expects to apply these amendments retrospectively. • Forfeitures : An entity can make an entity-wide accounting policy election to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures when they occur. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company expects to transition to accounting for forfeitures when they occur. This would result in approximately a $2.5 million unfavorable cumulative-effect adjustment to retained earnings/accumulated deficit to catch-up the previously unrecognized stock-based compensation associated with historical assumed forfeiture rates. Going forward, forfeitures will be recorded as favorable adjustments to stock-based compensation as they occur. • Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-withholding purposes : Cash paid by an employer when directly withholding shares for tax-withholding purposes should be classified as a financing activity. Retrospective application is required. Beginning in 2016, the Company began allowing certain members of management to have shares withheld for taxes when their restricted stock awards and performance units vest. As such, upon adopting the amendments in this ASU, the Company will need to present the amounts out of cash flows from operating activities and into cash flows from financing activities for the periods presented. For 2016, the amount was approximately $0.5 million .

Restricted Investments (Tables)

Restricted Investments (Tables)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Amortized Cost, Gross Unrealized Gains And Losses, Estimated Fair Value Of Fixed Maturity Securities	The following table presents the cost or amortized cost, gross unrealized gains and temporary losses, and estimated fair value of the Company's restricted investments: December 31, 2016 Gross Unrealized Cost or Amortized Cost Gains Temporary Estimated Fair Value (In thousands) United States corporate securities $ 16,432 $ — $ (23 ) $ 16,409 Municipal bonds 4,760 — (6 ) 4,754 Negotiable certificates of deposit 1,525 — — 1,525 Restricted investments, held to maturity $ 22,717 $ — $ (29 ) $ 22,688 December 31, 2015 Gross Unrealized Cost or Amortized Cost Gains Temporary Estimated Fair Value (In thousands) United States corporate securities $ 16,686 $ 2 $ (27 ) $ 16,661 Municipal bonds 4,904 1 (1 ) 4,904 Negotiable certificates of deposit 1,625 — — 1,625 Restricted investments, held to maturity $ 23,215 $ 3 $ (28 ) $ 23,190

Accounts Receivable, net (Table

Accounts Receivable, net (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Schedule of Accounts Receivable	Accounts receivable balances were as follows: December 31, 2016 2015 (In thousands) Trade customers $ 404,556 $ 415,219 Equipment manufacturers 4,755 6,801 Other 15,731 18,329 Accounts receivable 425,042 440,349 Less: Allowance for doubtful accounts (16,449 ) (17,928 ) Accounts receivable, net $ 408,593 $ 422,421 The following is a rollforward of the allowance for doubtful accounts: December 31, 2016 2015 2014 (In thousands) Beginning balance $ 17,928 $ 9,924 $ 7,504 Provision (Reduction) (1,147 ) 8,004 2,844 Recoveries (332 ) — 89 Write-offs — — (513 ) Ending balance $ 16,449 $ 17,928 $ 9,924 Notes receivable are included in "Current portion of notes receivable" and "Other assets" in the consolidated balance sheets and were comprised of: December 31, 2016 2015 (In thousands) Notes receivable due from owner-operators, with interest rates at 15%, secured by revenue equipment. Terms range from several months to four years $ 10,253 $ 15,725 Other — 24 Notes receivable 10,253 15,749 Less: current portion of notes receivable (6,961 ) (9,817 ) Notes receivable, less current portion $ 3,292 $ 5,932

Assets Held for Sale (Tables)

Assets Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment Assets Held-for-sale Disclosure [Abstract]
Schedule Of Assets Held for Sale	Assets held for sale balances were: December 31, 2016 2015 (In thousands) Land and facilities $ 288 $ 288 Revenue equipment 6,681 8,796 Assets held for sale $ 6,969 $ 9,084

Notes Receivable (Tables)

Notes Receivable (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Schedule of Accounts Receivable	Accounts receivable balances were as follows: December 31, 2016 2015 (In thousands) Trade customers $ 404,556 $ 415,219 Equipment manufacturers 4,755 6,801 Other 15,731 18,329 Accounts receivable 425,042 440,349 Less: Allowance for doubtful accounts (16,449 ) (17,928 ) Accounts receivable, net $ 408,593 $ 422,421 The following is a rollforward of the allowance for doubtful accounts: December 31, 2016 2015 2014 (In thousands) Beginning balance $ 17,928 $ 9,924 $ 7,504 Provision (Reduction) (1,147 ) 8,004 2,844 Recoveries (332 ) — 89 Write-offs — — (513 ) Ending balance $ 16,449 $ 17,928 $ 9,924 Notes receivable are included in "Current portion of notes receivable" and "Other assets" in the consolidated balance sheets and were comprised of: December 31, 2016 2015 (In thousands) Notes receivable due from owner-operators, with interest rates at 15%, secured by revenue equipment. Terms range from several months to four years $ 10,253 $ 15,725 Other — 24 Notes receivable 10,253 15,749 Less: current portion of notes receivable (6,961 ) (9,817 ) Notes receivable, less current portion $ 3,292 $ 5,932

Goodwill and Other Intangible42

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill [Table Text Block]	The following presents the components of goodwill by reportable segment as of December 31, 2016 and 2015 : Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount (In thousands) Truckload goodwill $ 376,998 $ (190,394 ) $ 186,604 Dedicated goodwill 130,742 (64,090 ) 66,652 Goodwill $ 507,740 $ (254,484 ) $ 253,256
Schedule of Intangible Assets, net [Table Text Block]	Intangible asset balances were as follows: December 31, 2016 2015 (In thousands) Customer Relationships: Gross carrying value $ 275,324 $ 275,324 Accumulated amortization (190,056 ) (173,242 ) Customer relationships, net 85,268 102,082 Trade Name: Gross carrying value 181,037 181,037 Intangible assets, net $ 266,305 $ 283,119
Finite-lived Intangible Assets Amortization Expense [Table Text Block]	In conjunction with the 2007 Transactions, definite-lived intangible assets with a gross carrying value of $261.2 million were recorded. Amortization of intangibles consisted of the following: Year Ended December 31, 2016 2015 2014 (In thousands) Amortization of intangible assets related to the 2007 Transactions $ 15,648 $ 15,648 $ 15,648 Amortization related to intangible assets existing prior to the 2007 Transactions 1,166 1,166 1,166 Amortization of intangibles $ 16,814 $ 16,814 $ 16,814

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2016
Accrued Liabilities [Abstract]
Schedule of Accrued Liabilities	The following table presents the composition of accrued liabilities: December 31, 2016 2015 (In thousands) Employee compensation (1) $ 51,217 $ 55,750 Owner-operator lease purchase reserve 6,229 5,271 Income tax accrual 5,119 2,043 Accrued owner-operator expenses 6,333 6,711 Deferred revenue 2,111 1,740 Fuel and property taxes 6,160 4,076 Accrued interest expense 1,819 1,532 Accrued legal (2) 28,778 2,701 Other (2)(3) 24,946 17,489 Accrued liabilities $ 132,712 $ 97,313 ____________ (1) The Company maintains a 401(k) benefit plan available to all employees who are 21 years of age or older and have completed six months of service. Under the plan, the Company has the option to match employee discretionary contributions up to 3% of an employee's compensation. Employees' rights to employer contributions vest after five years from their date of employment. For the years ended December 31, 2016 , 2015 , and 2014 , the Company's employee benefits expense for matching contributions, included in "Salaries, wages, and employee benefits" in the consolidated income statements, was approximately $5.7 million , $5.6 million , and $4.7 million , respectively. As of December 31, 2016 and 2015 , the balance includes $6.1 million and $5.9 million in matching contributions, respectively, to the plan in respect of such matching contributions. (2) The Company has disaggregated "Accrued legal" from "Other" as of December 31, 2016, and retrospectively adjusted the presentation as of December 31, 2015 for comparative purposes. See Note 17 for further details regarding the Company's legal accruals. (3) Includes the current portion of accrued consulting fees for Jerry Moyes. See Note 23 for further details.

Claims Accruals (Tables)

Claims Accruals (Tables)	12 Months Ended
	Dec. 31, 2016
Liability for Claims and Claims Adjustment Expense [Abstract]
Schedule of Claims Accruals	Claims accruals were comprised of the following: December 31, 2016 2015 (In thousands) Auto and collision liability $ 128,643 $ 123,086 Workers’ compensation liability 101,232 92,608 Owner-operator claims liability 11,736 12,304 Cargo damage liability 4,695 5,348 Other liability (1) 286 364 Claims accruals 246,592 233,710 Less: current portion of claims accruals (80,866 ) (84,429 ) Claim accruals, less current portion $ 165,726 $ 149,281 ____________ (1) Includes group medical liability. Effective January 1, 2015, the Company is fully insured on its group medical benefits, subject to contributed premiums. Prior to January 1, 2015, the Company had a $500 thousand specific deductible with an aggregating individual deductible of $150 thousand of each employee health care claim, as well as commercial insurance for the balance.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	The following table presents the Company's income tax expense: Year Ended December 31, 2016 2015 2014 (In thousands) Current expense: Federal $ 88,689 $ 76,737 $ 81,117 State 10,610 8,826 8,861 Foreign 3,053 8,783 4,107 102,352 94,346 94,085 Deferred (benefit) expense: Federal (31,380 ) 24,097 (4,189 ) State (211 ) 3,419 1,975 Foreign (5,059 ) (2,653 ) (2,397 ) (36,650 ) 24,863 (4,611 ) Income tax expense $ 65,702 $ 119,209 $ 89,474
Schedule Of Effective Income Tax Rate Reconciliation	Actual tax expense differs from expected tax expense as follows: Year Ended December 31, 2016 2015 2014 (In thousands) Computed "expected" tax expense $ 75,239 $ 110,875 $ 87,719 Increase (decrease) in income taxes resulting from: State income taxes, net of federal income tax benefit 6,443 8,745 6,866 Domestic Production Activities Deduction (1) (7,777 ) — — Toll Roads income tax credit (2) (4,082 ) — — Other (4,121 ) (411 ) (5,111 ) Income tax expense $ 65,702 $ 119,209 $ 89,474 ____________ (1) Domestic Production Activities Deduction — Internal Revenue Code Section 199 permits taxpayers to claim a deduction from taxable income attributable to certain domestic production activities such as the development of computer software and the manufacturing of goods. Beginning in 2010 and thereafter, the deduction is equal to 9% of the smaller of a taxpayer’s qualified production activities or taxable income. Due to its increased software development efforts, the Company has elected to take the deduction in the current year and preceding open tax years. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to a domestic production activities deduction on the Company's 2015 federal tax return. The Company also received tax benefits for years ending December 31, 2016, December 31, 2014, and December 31, 2013. The Company generated $6.4 million , $6.2 million , $6.2 million , and $3.4 million in domestic production activities deductions for the development of computer software in 2016, 2015, 2014, and 2013, respectively. This resulted in approximately $2.2 million , $2.2 million , $2.2 million , and $1.2 million in tax benefits in 2016, 2015, 2014, and 2013, respectively. (2) Toll roads income tax credit — Trans-Mex, our Mexico trucking subsidiary, qualified for an income tax credit equal to 50% of the qualified tolls paid. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to the toll road income tax credit reported on the 2015 income tax return. Trans-Mex also will claim a toll road income tax credit for 2016. Trans-Mex paid $5.6 million and $6.5 million in qualifying tolls during 2016 and 2015, respectively. This resulted in approximately $1.8 million and $2.3 million in tax benefits in 2016 and 2015, respectively.
Components Of Net Deferred Tax Asset (Liability)	The components of the net deferred tax asset (liability) included in "Deferred income taxes" in the consolidated balance sheets were: December 31, 2016 2015 (In thousands) Deferred tax assets: Self-insurance accruals $ 73,654 $ 66,949 Allowance for doubtful accounts 8,036 11,448 Amortization of stock options 6,397 8,923 Accrued liabilities 15,366 1,773 Vacation accrual 5,358 4,990 Other 8,940 11,589 Total deferred tax assets 117,751 105,672 Valuation allowance — — Total deferred tax assets, net 117,751 105,672 Deferred tax liabilities: Property and equipment, principally due to differences in depreciation (420,975 ) (434,802 ) Prepaid taxes, licenses, and permits deducted for tax purposes (13,284 ) (14,083 ) Cancellation of debt (3,747 ) (5,622 ) Intangible assets (106,143 ) (110,546 ) Other (1,324 ) (4,451 ) Deferred tax liabilities (545,473 ) (569,504 ) Deferred income taxes $ (427,722 ) $ (463,832 )
Reconciliation Of Unrecognized Tax Benefits	The following is a rollforward of our unrecognized tax benefits: Year Ended December 31, 2016 2015 2014 (In thousands) Unrecognized tax benefits at beginning of year $ 1,739 $ 1,739 $ 2,385 Increases for tax positions taken prior to beginning of year — — 95 Decreases for tax positions taken prior to beginning of year (975 ) — (741 ) Unrecognized tax benefits at end of year $ 764 $ 1,739 $ 1,739

Accounts Receivable Securitiz46

Accounts Receivable Securitization (Tables)	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing of Financial Assets [Abstract]
Accounts Receivable Securitization [Table Text Block]	The following table summarizes the key attributes of the current and previous securitization programs: 2015 RSA 2013 RSA (Dollars in thousands) Effective December 2015 June 2013 Borrowing capacity (1) $400,000 $375,000 Final maturity date January 10, 2019 July 13, 2016 Unused commitment fee rate 35 basis points 35 basis points Program fees on outstanding balances one-month LIBOR + 90 basis points one-month LIBOR + 95 basis points ____________ (1) The 2015 RSA has an accordion option to increase the maximum borrowing capacity by up to an additional $75.0 million , subject to participation by the Purchasers. The 2013 RSA borrowing capacity included a $50.0 million accordion option, which was exercised in September 2014.

Debt And Financing (Tables)

Debt And Financing (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of Debt Balances by Instrument [Table Text Block]	Other than the Company's accounts receivable securitization as discussed in Note 12 and its outstanding capital lease obligations as discussed in Note 15 , the Company's long-term debt consisted of the following: December 31, 2016 2015 (In thousands) 2015 Agreement: New Term Loan A, due July 2020, net of $1,338 and $1,695 DLCs as of December 31, 2016 and 2015 respectively (1) $ 492,912 $ 668,055 Other 8,893 11,122 Long-term debt 501,805 679,177 Less: current portion of long-term debt, net of $0 and $68 DLCs as of December 31, 2016 and 2015 respectively (8,459 ) (35,514 ) Long-term debt, less current portion $ 493,346 $ 643,663 December 31, 2016 2015 (In thousands) Long-term debt $ 501,805 $ 679,177 Revolving line of credit, due July 2020 (2) 130,000 200,000 Long-term debt, including revolving line of credit $ 631,805 $ 879,177 ____________ (1) Refer to Note 21 for information regarding the fair value of debt. (2) The Company also had outstanding letters of credit under the New Revolver, primarily related to workers' compensation and self-insurance liabilities of $97.0 million at December 31, 2016 and $95.0 million at December 31, 2015 .
Schedule of Long-term Debt Instruments [Table Text Block]	The following table presents the key terms of the 2015 Agreement: 2015 Agreement New Term Loan A New Revolver (2) (Dollars in thousands) Maximum borrowing capacity $680,000 $600,000 Final maturity date July 27, 2020 July 27, 2020 Interest rate base LIBOR LIBOR LIBOR floor —% —% Interest rate minimum margin (1) 1.50% 1.50% Interest rate maximum margin (1) 2.25% 2.25% Minimum principal payment — amount (3) $6,625 $— Minimum principal payment — frequency Quarterly Once Minimum principal payment — commencement date (3) December 31, July 27, ____________ (1) The interest rate margin for the New Term Loan A and New Revolver is based on the Company's consolidated leverage ratio. As of December 31, 2016 , interest accrued at 2.18% on the New Term Loan A and 2.18% on the New Revolver. As of December 31, 2015 , interest accrued at 2.12% on the New Term Loan A and 2.08% on the New Revolver. (2) The commitment fee for the unused portion of the New Revolver is based on the Company's consolidated leverage ratio, and ranges from 0.25% to 0.35% . As of December 31, 2016 , commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.50% . As of December 31, 2015 , commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.75% . (3) Commencing in March 2017, the minimum required quarterly payment on the New Term Loan A is $12.3 million , at which it would remain until final maturity. However, as of January 2017, the Company voluntarily prepaid all minimum quarterly principal payments through final maturity.
Schedule of Debt [Table Text Block]	The following table presents the key terms of the 2014 Agreement: Insert Title Here 2014 Agreement Old Term Loan A Term Loan B Old Revolver (2) (Dollars in thousands) Maximum borrowing capacity $500,000 $400,000 $450,000 Final maturity date June 9, 2019 June 9, 2021 June 9, 2019 Interest rate base LIBOR LIBOR LIBOR LIBOR floor —% 0.75% —% Interest rate minimum margin (1) 1.50% 3.00% 1.50% Interest rate maximum margin (1) 2.25% 3.00% 2.25% Minimum principal payment — amount (3) $5,625 $1,000 $— Minimum principal payment — frequency Quarterly Quarterly Once Minimum principal payment — commencement date (3) March 31, 2015 June 30, 2014 June 30, 2019 ____________ (1) Interest rate margins on the Old Term Loan A and Old Revolver were based on the Company's consolidated leverage ratio. Additionally, after December 31, 2014, interest rate margins on the Term Loan B were determined by the Company's consolidated leverage ratio, ranging from 2.75% to 3.00% . (2) The commitment fee for the unused portion of the Old Revolver was also based on the Company's consolidated leverage ratio, and ranged from 0.25% to 0.35% . (3) Commencing in March 2017, the minimum principal payment amount on the Old Term Loan A would have been $11.3 million .

Deferred Loan Costs (Tables)

Deferred Loan Costs (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt Issuance Costs [Table Text Block]	The following table presents the classification of DLCs in the Company's consolidated balance sheets: December 31, 2016 2015 (In thousands) ASSETS: Other assets $ 1,169 $ 1,496 LIABILITIES: Current portion of long-term debt — 68 Long-term debt, less current portion 1,338 1,627 Accounts receivable securitization 715 1,073 Total DLCs $ 3,222 $ 4,264

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Schedule of future minimum lease commitments [Table Text Block]	As of December 31, 2016 , annual future minimum lease payments for all noncancelable leases were: Operating Capital (In thousands) 2017 $ 203,463 $ 77,925 2018 144,205 49,965 2019 92,065 60,212 2020 44,592 13,669 2021 23,231 29,890 Thereafter 48,813 17,268 Future minimum lease payments $ 556,369 $ 248,929 Less: amounts representing interest (14,993 ) Present value of minimum lease payments 233,936 Less: current portion (72,473 ) Capital lease obligations, less current portion $ 161,463
Schedule of future minimum lease payments receivable [Table Text Block]	Annual future minimum lease payments receivable under operating leases for the periods noted below were: (In thousands) 2017 $ 109,077 2018 64,615 2019 27,739 2020 9,752 2021 9 Thereafter — Future minimum lease payments receivable $ 211,192

Contingencies and Legal Proce50

Contingencies and Legal Proceedings (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Schedule of Loss Contingencies by Contingency [Table Text Block]	Legal Proceedings Information is provided below regarding the nature, status, and contingent loss amounts, if any, associated with the Company's pending legal matters. There are inherent uncertainties in these legal matters, some of which are beyond management's control, making the ultimate outcomes difficult to predict. Moreover, management's views and estimates related to these matters may change in the future, as new events and circumstances arise and the matters continue to develop. For the matters below, an estimate of the possible loss or range of loss cannot be determined for certain cases because, among other reasons, (1) the proceedings are in various stages that do not allow for assessment; (2) damages have not been sought; (3) damages are unsupported and/or exaggerated; (4) there is uncertainty as to the outcome of pending appeals; and/or (5) there are significant factual issues to be resolved. Based on currently available information, and in certain cases, advice of outside counsel, management does not believe that loss contingencies arising from pending matters will have a material adverse effect on the Company's overall financial position, after taking into consideration any existing accruals. However, actual outcomes could be material to the Company's operating results or liquidity for any particular period. EMPLOYEE COMPENSATION AND PAY PRACTICES MATTERS Aggregate information regarding accruals for the below employee compensation and pay practices matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $1.0 million $— - $0.3 million For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made. California Private Attorneys General Act ("PAGA") Class Action The plaintiff alleges that the Company violated California law by failing to timely pay wages and failing to reimburse employees for business expenses. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Theron Christopher (1) Swift Transportation Co. of Arizona, LLC July 8, 2016 Superior Court of California, County of Riverside Recent Developments and Current Status The PAGA matter is in its initial phases and is expected to move into discovery. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Wage, Meal, and Rest: Driver Class Actions The plaintiffs generally allege one or more of the following: that the Company 1) failed to pay the California minimum wage; 2) failed to provide proper meal and rest periods; 3) failed to timely pay wages upon separation from employment; 4) failed to pay for all hours worked; 5) failed to pay overtime; 6) failed to properly reimburse work-related expenses; and 7) failed to provide accurate wage statements. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in John Burnell (1) Swift Transportation Co., Inc March 22, 2010 United States District Court for the Central District of California James R. Rudsell (1) Swift Transportation Co. of Arizona, LLC and Swift Transportation Company April 5, 2012 United States District Court for the Central District of California Lawrence Peck (1) Swift Transportation Co. of Arizona, LLC September 25, 2014 United States District Court for the Central District of California Lawrence Peck (1)(2) Swift Transportation Co. of Arizona, LLC, et al. November 20, 2014 Superior Court of California, County of Riverside Sadashiv Mares (1) Swift Transportation Co. of Arizona, LLC February 27, 2015 United States District Court for the Central District of California Rafael McKinsty (1) Swift Transportation Co. of Arizona, LLC, et al. April 15, 2015 United States District Court for the Central District of California Thor Nilsen (1) Swift Transportation Co. of Arizona, LLC October 15, 2015 United States District Court for the Central District of California Recent Developments and Current Status Before and during 2016, the Rudsell, Peck, Peck PAGA, Mares, McKinsty, and Nilsen complaints were stayed, pending resolution of earlier-filed cases. In May 2016, the Burnell plaintiffs were denied class certification. Their subsequent petition to appeal the decertification order was also denied. Following the Burnell plaintiffs' failure to certify the class, the stays on certain cases were lifted. Those cases are now in discovery. Based on the current procedural nature of the cases, the final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Wage, Meal, and Rest: Yard Hostler Class Actions The plaintiffs, representing yard hostlers employed by the Company in California, generally allege one or more of the following: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime and doubletime wages required by California law; 3) failed to provide accurate, itemized wage statements; 4) failed to timely pay wages upon separation from employment; 5) failed to reimburse for business expenses; and 6) failed to provide proper meal and rest periods. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Grant Fritsch (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Company January 28, 2016 Superior Court of California, County of San Bernardino Bill Barker, Tab Bachman, and William Yingling (1) Swift Transportation Company of Arizona, LLC April 1, 2016 United States District Court for the Eastern District of California Recent Developments and Current Status The Barker and Fritsch complaints are currently in discovery. The Company retains all of its defenses against liability and damages related to these lawsuits. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of these matters and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. National Customer Service Misclassification Class Action The plaintiff, a former Customer Service Representative IV, alleges that the Company failed to pay overtime under the FLSA. Additionally, with respect to California state law, the plaintiff alleges that the Company: 1) failed to pay overtime; 2) failed to pay timely final wages; 3) failed to provide meal and rest periods; and 4) violated the unfair competition law. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Salvador Castro (1) Swift Transportation Co. of Arizona, LLC May 11, 2016 United States District Court for the Central District of California Recent Developments and Current Status Castro, along with five other former Customer Service Representative IV employees opted into this collective action lawsuit, which was being pursued under the FLSA. In addition to the Castro collective action, thirteen Customer Service Representative IV employees pursued similar claims in individual arbitrations. The parties conducted three arbitrations regarding the individual claimants. The parties agreed to mediation, which was held in January 2017. The parties are currently finalizing a global settlement of the collective action and the individual arbitrations. Arizona Fair Labor Standards Act Class Action The plaintiff alleges that the Company violated the FLSA by failing to pay its trainee drivers minimum wage for all work performed and by failing to pay overtime. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Pamela Julian (1) Swift Transportation Inc., et al. December 29, 2015 United States District Court for the District of Arizona Recent Developments and Current Status In March 2016, the Company filed a motion to dismiss the plaintiff's overtime claims, which was granted by the district court in May 2016. The plaintiff recently filed a Motion for Conditional Class Certification, which the Company intends to oppose. The Company retains all of its defenses against liability and damages for the remaining claims. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Washington Overtime Class Actions The plaintiffs allege one or more of the following, pertaining to Washington state-based drivers: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime; 3) failed to pay all wages due at established pay periods; 4) failed to provide proper meal and rest periods; 5) failed to provide accurate wage statements; and 6) unlawfully deducted from employee wages. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Troy Slack (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation September 9, 2011 United States District Court for the Western District of Washington Julie Hedglin (1) Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation January 14, 2016 United States District Court for the Western District of Washington Recent Developments and Current Status The parties in the Slack matter are finishing discovery and the next step will be for the parties to file dispositive motions. The case is scheduled for trial in September 2017. The Hedglin matter is currently in discovery. The Company retains all of its defenses against liability and damages for both matters. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. ___________ (1) Individually and on behalf of all others similarly situated. (2) Peck PAGA complaint. OWNER-OPERATOR MATTERS Aggregate information regarding accruals for the below owner-operator matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $25.0 million $— - $44.0 million For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made. Arizona Owner-operator Class Action The putative class alleges that the Company improperly compensated owner-operators (later expanding the class to include employee drivers) using the contracted and industry standard remuneration based upon dispatched miles, instead of using a method of calculating mileage that the plaintiffs allege would be more accurate. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Leonel Garza (1) Swift Transportation Co., Inc. January 30, 2004 Arizona Supreme Court Recent Developments and Current Status The original trial court's decision was to deny class certification of the owner-operators, which was reversed and reinstated several times by various courts prior to 2016. The class is currently certified, based on an appellate court's decision from July 2016. The Company filed a petition for review with the Arizona Supreme Court in August 2016, which was denied in January 2017. The matter will now proceed in the Maricopa County Superior Court. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Ninth Circuit Owner-operator Misclassification Class Action The putative class alleges that the Company misclassified owner-operators as independent contractors in violation of the FLSA and various state laws, and that such owner-operators should be considered employees. The lawsuit also raises certain related issues with respect to the lease agreements that certain owner-operators have entered into with IEL. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Joseph Sheer, Virginia Van Dusen, Jose Motolinia, Vickii Schwalm, Peter Wood (1) Swift Transportation Co., Inc., Interstate Equipment Leasing, Inc., Jerry Moyes, and Chad Killebrew December 22, 2009 Unites States District Court of Arizona and Ninth Circuit Court of Appeals Recent Developments and Current Status For several years, the parties have been arguing over the proper venue in which to proceed. The plaintiffs argue that they signed contracts of employment, thus exempting them from arbitration under the Federal Arbitration Act, and claim that their case should be heard in court by a judge. The Company takes the position that these individuals signed independent contractor agreements and therefore can properly be required to submit their claims to arbitration. In January 2017, the district court issued an order finding that the plaintiffs had signed contracts of employment and thus the case could properly proceed in court. The Company has appealed this decision to the Ninth Circuit and will seek to stay the district court case, pending resolution of the appeal. The Company intends to vigorously defend against any proceedings. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. Utah Collective and Individual Arbitration The plaintiffs allege that the Central Parties (defined below) misclassified owner-operator drivers as independent contractors and were therefore liable to these drivers for minimum wages and other employee benefits under the FLSA. The complaint also alleges a federal forced labor claim under U.S.C. §1589 and §1595, as well as fraud and other state-law claims. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Gabriel Ciluffo, Kevin Shire, and Bryan Ratterree (1)(2) Central Refrigerated Service, Inc., Central Leasing, Inc., Jon Isaacson, and Jerry Moyes (the "Central Parties"), as well as Swift Transportation Company June 1, 2012 American Arbitration Association Recent Developments and Current Status In June 2016, mediation commenced, but there was ultimately no settlement of the matter. In October 2016, the arbitrator ruled that approximately 1,300 Central Refrigerated Service, Inc. drivers were misclassified as independent contractors, and should have been compensated as employees. The arbitrator ruled that damages could be assessed in a collective proceeding and declined to decertify the collective proceeding. Based on the October 2016 arbitration ruling, the Company increased its accrual related to this matter. A damages trial is scheduled for April 2017. No trial date on the claimants' damages has been set by the arbitrator. The Company and the Central Parties dispute the arbitrator's rulings to date and intend to continue to vigorously defend against the plaintiffs' claims in both the collective action and individual proceedings. The likelihood that a loss has been incurred is probable. ___________ (1) Individually and on behalf of all others similarly situated. (2) In addition to the collective arbitration that is pending before the American Arbitration Association ("AAA"), the named plaintiffs, along with approximately 325 other owner-operators, have initiated a series of individual, bilateral proceedings against the Central Parties with the AAA. Discovery is commencing in these individual cases, which are pending before various separate arbitrators. A sample of these cases will be litigated and proceed to hearing, while the remaining cases will be stayed. Trials for the sample cases are expected to occur in the second quarter of 2017. EMPLOYEE HIRING PRACTICES MATTERS Aggregate information regarding accruals for the below employee hiring practices matters: Aggregate accrual Aggregate range of loss in excess of accrual Explanation if no accrual has been made $— $— - $— It is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated for these matters. Indiana Fair Credit Reporting Act Class Action The plaintiff alleges that Central Refrigerated Service, Inc. violated the Fair Credit Reporting Act by failing to provide job applicants with adverse action notices and copies of their consumer reports and statements of rights. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Melvin Banks (1) Central Refrigerated Service, Inc. March 18, 2015 United States District Court for the District of Arizona Recent Developments and Current Status The first phase of discovery, regarding potential for identifying and certifying a class of affected job applicants, has been completed. The parties are currently completing a class certification briefing and the Company filed a Motion for Summary Judgment. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote. California Class and Collective Action for Pre-employment Physical Testing The plaintiff alleges that pre-employment tests of physical strength administered by a third party on behalf of Central Refrigerated Service, Inc. had an unlawfully discriminatory impact on female applicants and applicants over the age of 40. The suit seeks damages under Title VII of the Civil Rights Act of 1964, the age Discrimination Act, and parallel California state law provisions, including the California Fair Employment and Housing Act. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in Robin Anderson (1) Central Refrigerated Service, Inc., Workwell Systems, Inc., and Swift Transportation Company October 6, 2014 United States District Court for the Central District of California Recent Developments and Current Status Litigation is at a very preliminary stage and no trial date has been set. There is no information available regarding the number of potential members of the putative class or collective actions. The Company intends to vigorously defend against the merits of the plaintiff's claims and to oppose certification of any class of plaintiffs. The final disposition of this case and the financial impact cannot be determined at this time. The likelihood that a loss has been incurred is remote. ___________ (1) Individually and on behalf of all others similarly situated.

Common Stock (Tables)

Common Stock (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Class of Treasury Stock [Table Text Block]	The following table presents our repurchases of our Class A common stock under the respective share repurchase programs, net of advisory fees: Year Ended December 31, As of December 31, Share Repurchase Program 2016 2015 2016 Authorized Amount Board Approval Date Shares Amount Shares Amount Amount Remaining (In thousands) $100,000 September 24, 2015 2,221 $ 30,000 4,176 $ 70,000 $ — $150,000 February 22, 2016 5,162 $ 87,119 — $ — $ 62,881 7,383 $ 117,119 4,176 $ 70,000 $ 62,881 No share repurchases were made during the year ended December 31, 2014 .
Schedule of Conversions of Stock [Table Text Block]	During 2016 and 2014 , the Moyes Affiliates converted shares of common stock on a one-for-one basis as follows: Transaction Date Converted from Class B Converted to (In thousands) May 4, 2016 (1,250 ) 1,250 May 30, 2014 (1,450 ) 1,450 There were no shares converted in 2015.

Stock Plans (Tables)

Stock Plans (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation Expense Related To Stock-Based Compensation	Stock-based compensation expense, which is included in "Salaries, wages, and employee benefits" in the consolidated income statements is comprised of the following: Year Ended December 31, 2016 2015 2014 (In thousands) Stock options $ 1,550 $ 1,333 $ 3,007 RSUs and restricted stock 4,467 3,939 1,600 Performance units (1) — 1,253 789 Total stock-based compensation expense $ 6,017 $ 6,525 $ 5,396 Income tax benefit $ 1,841 $ 2,453 $ 1,926 ____________ (1) Targets for the performance units granted in 2014 and 2015 are not expected to be achieved.
Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block]	The following table presents the total unrecognized stock-based compensation expense and the expected weighted average period over which these expenses will be recognized: December 31, 2016 Expense Weighted Average Period (In thousands) (In years) Stock options $ 682 1.35 RSUs and restricted stock $ 7,979 1.31 Performance units $ 478 2.00
Summary Of Activity Related To Stock Options	A summary of the activity related to stock options for the year ended December 31, 2016 follows: Shares Under Option Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (1) (In years) (In thousands) Stock options outstanding at December 31, 2015 3,224,253 $ 11.01 4.04 $ 9,051 Granted 195,999 $ 15.51 Exercised (1,253,152 ) $ 10.56 Expired (11,119 ) $ 13.46 Forfeited (37,818 ) $ 18.87 Stock options outstanding at December 31, 2016 2,118,163 $ 13.42 4.19 $ 23,175 Aggregate number of stock options expected to vest at a future date as of December 31, 2016 234,300 $ 20.93 8.53 $ 803 Exercisable at December 31, 2016 1,849,432 $ 12.32 3.56 $ 22,269 ____________ (1) The aggregate intrinsic value was computed using the closing share price on December 31, 2016 of $24.36 and on December 31, 2015 of $13.82 , as applicable.
Weighted Average Assumptions	The following table presents the weighted average assumptions used to determine the fair value of stock options issued: Year Ended December 31, 2016 2015 2014 Dividend yield (1) —% —% —% Risk-free rate of return (2) 1.23% 1.41% 1.28% Expected volatility (3) 40.33% 37.22% 40.00% Expected term (in years) (4) 4.9 5.8 5.8 Weighted average fair value of stock options granted $6.39 $6.96 $6.79 ____________ (1) The dividend yield assumption is based on anticipated dividend payouts. (2) The risk-free interest rate assumption is based on the United States Treasury yield curve at the grant date with maturity dates approximately equal to the expected life at the grant date. (3) The Company estimates the expected volatility and expected option life assumption consistent with ASC Topic 718, Compensation – Stock Compensation . Beginning in 2016, we used our internal historical prices over the expected term of the options to determine our expected volatility. Prior to that, expected volatility was based upon an analysis of historical prices of similar market capitalized trucking group participants within the Dow Jones Total United States Market Index over the expected term of the options. The Company chose a daily measurement interval for historical volatility as it believes this better depicts the nature of employee option exercise decisions being based on shorter-term trends in the price of the underlying shares, rather than on monthly price movements. (4) As a result of the inability to predict the expected future employee exercise behavior, the Company estimated the expected term of the options using a simplified method based on contractual and vesting terms of the options. The Company uses historical data to estimate pre-vesting option forfeitures and records stock-based compensation expense only for those awards that are expected to vest.
Summary Of Exercise Of Stock Options	The following table summarizes stock option exercise information for the years presented: Year Ended December 31, 2016 2015 2014 (In thousands, except share data) Number of stock options exercised 1,253,152 665,531 1,100,998 Intrinsic value of stock options exercised $ 14,266 $ 9,695 $ 15,830 Cash received upon exercise of stock options $ 13,237 $ 6,953 $ 11,488 Income tax benefit $ 2,575 $ 2,147 $ 3,730
Rollforward of Company's Nonvested Stock Options	The following table is a rollforward of the Company's nonvested stock options: Stock Options Shares Weighted Average Fair Value Nonvested stock options at December 31, 2015 503,740 $ 6.92 Granted 195,999 $ 6.39 Vested (393,190 ) $ 6.09 Forfeited (37,818 ) $ 6.82 Nonvested stock options at December 31, 2016 268,731 $ 6.22
Schedule of Grants of Restricted Stock [Table Text Block]	The following table presents restricted stock awards granted under the 2014 Stock Plan: Year Ended December 31, 2016 2015 2014 RSUs granted to company employees 300,150 212,272 203,968 Restricted stock shares granted to the Board 32,235 16,601 17,102 Total restricted stock awards granted 332,385 228,873 221,070
Rollforward of Nonvested Restricted Stock Awards [Table Text Block]	The following table is a rollforward of nonvested restricted stock awards: Restricted Stock Awards Number of Awards Weighted Average Fair Value Nonvested restricted stock awards at December 31, 2015 418,281 $ 22.54 Granted 332,385 $ 15.54 Vested (1) (210,102 ) $ 21.36 Forfeited (27,242 ) $ 21.14 Nonvested restricted stock awards at December 31, 2016 (2) 513,322 $ 18.55 ____________ (1) Includes 19,221 shares of restricted stock previously issued to Board members, and vested during 2016 . (2) Includes 32,235 shares of restricted stock previously issued to Board members, but not yet vested as of December 31, 2016 .
Rollforward of Nonvested Performance Shares [Table Text Block]	The following table is a rollforward of nonvested performance units: Performance Units Shares Weighted Average Fair Value Nonvested performance units at December 31, 2015 215,333 $ 18.99 Granted 91,492 $ 15.51 Vested (1) (96,650 ) $ 13.36 Forfeited (5,005 ) $ 24.00 Nonvested performance units at December 31, 2016 205,170 $ 19.97 ____________ (1) The performance period for the performance units granted in May 2014 ended on December 31, 2016 . The Board is not expected to approve the final vesting of these awards subsequent to December 31, 2016 , based on the results of the three -year performance period, but final decision is still pending as of the filing date of this Annual Report on Form 10-K.

Weighted Average Shares Outst53

Weighted Average Shares Outstanding (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Calculation Of Basic And Diluted Earnings Per Share Attributable To Stockholders	The following table reconciles basic weighted average shares outstanding to diluted weighted average shares outstanding: December 31, 2016 2015 2014 (In thousands) Basic weighted average common shares outstanding 134,139 142,018 141,431 Dilutive effect of stock options 1,355 1,650 2,044 Diluted weighted average common shares outstanding 135,494 143,668 143,475 Anti-dilutive shares excluded from diluted earnings per share (1) 156 354 162 ____________ (1) Shares were excluded from the dilutive-effect calculation because the outstanding options' exercise prices were greater than the average market price of the Company's common shares during the period.

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Carrying Amounts And Estimated Fair Values Of Financial Instruments	The following table presents the carrying amounts and estimated fair values of the Company's financial instruments: As of December 31, 2016 2015 Carrying Estimated Carrying Estimated (In thousands) Financial Assets: Restricted investments (1) $ 22,717 $ 22,688 $ 23,215 $ 23,190 Financial Liabilities: 2015 Agreement: New Term Loan A, due July 2020 (2) 492,912 494,250 668,055 669,750 Accounts receivable securitization, due January 2019 (3) 279,285 280,000 223,927 225,000 Revolving line of credit, due July 2020 130,000 130,000 200,000 200,000 ____________ The carrying amounts of the final instruments shown in the table are included in the consolidated balance sheets, as follows: (1) Restricted investments are included in "Restricted investments, held to maturity, amortized cost." (2) The New Term Loan A is included in "Current portion of long-term debt" and "Long-term debt, less current portion." Carrying value is net of $1.3 million and $1.7 million DLCs as of December 31, 2016 and 2015, respectively. (3) Carrying value is net of $0.7 million and $1.1 million DLCs as of December 31, 2016 and 2015, respectively.
Assets That Were Measured At Estimated Fair Value On Non-Recurring Basis	The following table presents assets measured at estimated fair value on a nonrecurring basis as of December 31, 2016 and 2015 : Fair Value Measurements at Reporting Date Using Estimated Fair Value Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Losses (In thousands) As of December 31, 2016 Software (1) $ — $ — $ — $ — $ (520 ) Equipment (2) 1,963 — — 1,963 (250 ) As of December 31, 2015 Note receivable (3) — — — — (1,480 ) _____________ (1) During the three months ended December 31, 2016, certain operations software related to the Company's logistics business was determined to be fully impaired based on a significant decrease in the expected useful life of the software. This resulted in a pre-tax impairment loss of $0.5 million , which was recorded in "Impairments" within operating income in the consolidated income statement. (2) During the three months ended December 31, 2016, management reassessed the fair value of certain IEL tractors, which had a total book value of $2.2 million , determining that there was a pre-tax impairment loss of $0.3 million . The impairment loss was recorded in "Impairments" within operating income in the consolidated income statement. (3) In September 2013, the Company agreed to advance up to $2.3 million , pursuant to an unsecured promissory note, to an independent fleet contractor that transported freight on Swift's behalf. In March 2015, management became aware that the independent contractor violated various covenants outlined in the unsecured promissory note, which created an event of default that made the principal and accrued interest immediately due and payable. As a result of this event of default, as well as an overall decline in the independent contractor's financial condition, management re-evaluated the fair value of the unsecured promissory note. At March 31, 2015, management determined that the remaining balance due from the independent contractor to the Company was not collectible, which resulted in a $1.5 million pre-tax adjustment that was recorded in "Non-cash impairments of non-operating assets" in the Company's consolidated income statements.

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Schedule Of Services Received And Provided By Company	Receivables and payables pertaining to these related party transactions were: As of December 31, 2016 2015 Receivable Payable Receivable Payable (In thousands) Thermo King $ — $ 22 $ 4 $ 46 Central Freight Lines 118 1 3 3 SME Industries 72 — 79 — Other Affiliates 3 — 5 29 Total $ 193 $ 23 $ 91 $ 78 The following table presents Swift's transactions with companies controlled by and/or affiliated with its related parties: Year Ended December 31, 2016 2015 2014 Provided by Swift Received by Swift Provided by Swift Received by Swift Provided by Swift Received by Swift (In thousands) Freight Services: Thermo King (1) $ 1 $ — $ 4 $ — $ — $ — Central Freight Lines (2) 83 26 237 25 25 24 SME Industries (2) 830 — 978 — 185 — Other Affiliates (2) — — — — 14 — Total $ 914 $ 26 $ 1,219 $ 25 $ 224 $ 24 Facility and Equipment Leases: Thermo King (1) $ — $ — $ 12 $ — $ — $ — Central Freight Lines (2) 1,154 372 1,090 435 843 400 Other Affiliates (2) 19 — 20 1 20 228 Total $ 1,173 $ 372 $ 1,122 $ 436 $ 863 $ 628 Other Services: Thermo King (1) $ — $ 633 $ 1 $ 518 $ — $ 184 Central Freight Lines (2) 24 — 142 — 388 — Swift Aircraft Management (2) — 501 — 636 — 699 SME Industries (2) 69 — — — — — Other Affiliates (2) 11 17 1 139 4 73 Total $ 104 $ 1,151 $ 144 $ 1,293 $ 392 $ 956 ____________ (1) Thermo King West, Inc. and Thermo King Chesapeake, Inc. are owned by William Riley III, a member of Swift's Board. Transactions associated with the Thermo King affiliated entities primarily consist of parts and equipment purchases by Swift. Swift also provided freight services, equipment leasing, and other services to the Thermo King affiliated entities. (2) Entities affiliated with majority shareholder, Board member, and (prior to December 31, 2016) Chief Executive Officer, Jerry Moyes include Central Freight Lines, SME Industries, Swift Aircraft Management, Compensi Services, Common Market Trading, LLC, and Southwest Premier Properties. Transactions with these entities that are controlled by and/or are otherwise affiliated with Jerry Moyes, include freight services, facility leases, equipment leases, and other services. • Freight Services Provided by Swift — The rates the Company charges for freight services to each of these companies for transportation services are market rates, which are comparable to rates charged to third-party customers. These transportation services provided to affiliates provide the Company with an additional source of operating revenue at its normal freight rates. • Freight Services Received by Swift — Transportation services received from Central Freight represent LTL freight services rendered to haul parts and equipment to Company shop locations. • Other Services Provided by Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services. • Other Services Received by Swift — Executive air transport, fuel storage, event fees, equipment purchases, miscellaneous repair services, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company. In 2015 , the Company purchased bulk diesel fuel totaling $63 thousand , from Common Market Trading LLC, which is also included in other services received by Swift from other affiliates. Common Market Trading LLC was initially owned by both Jerry Moyes and his brother, Ronald Moyes, but wholly owned by Ronald Moyes as of October 20, 2015. The Company purchased no bulk diesel fuel from Common Market Trading LLC in 2016.

Jerry Moyes' Retirement (Tables

Jerry Moyes' Retirement (Tables)	12 Months Ended
	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring and Related Costs [Table Text Block]	The following is a rollforward of the accrued liability for the consulting fees: (In thousands) Accrued consulting fees – Jerry Moyes, balance at December 31, 2015 $ — Additions to accrual 6,837 Less: payments (162 ) Accrued consulting fees – Jerry Moyes, balance at December 31, 2016 (1) $ 6,675 ____________ (1) The balance is included in "Other liabilities" (noncurrent) and "Accrued liabilities" (current) in the consolidated balance sheet, based on the timing of the expected payment. The $0.3 million impact of the equity award modification is excluded from the accrual balance because it is classified as "Additional paid-in capital" in the consolidated balance sheet.

Information by Segment, Geogr57

Information by Segment, Geography, and Customer Concentration (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Summary Of Financial Information By Segments	The following tables present the Company's financial information by segment: Year Ended December 31, 2016 2015 2014 Operating revenue: (In thousands) Truckload $ 2,048,049 $ 2,204,114 $ 2,301,010 Dedicated 971,246 927,657 892,078 Swift Refrigerated 341,280 380,251 417,980 Intermodal 360,157 390,572 401,577 Subtotal 3,720,732 3,902,594 4,012,645 Non-reportable segments 386,349 407,781 342,969 Intersegment eliminations (75,564 ) (81,053 ) (56,890 ) Consolidated operating revenue $ 4,031,517 $ 4,229,322 $ 4,298,724 Year Ended December 31, 2016 2015 2014 Operating income (loss): (In thousands) Truckload $ 181,781 $ 257,007 $ 258,072 Dedicated 108,481 82,735 75,794 Swift Refrigerated (12,844 ) 17,080 14,035 Intermodal (547 ) 4,128 8,298 Subtotal 276,871 360,950 356,199 Non-reportable segments (34,859 ) 9,154 13,871 Consolidated operating income $ 242,012 $ 370,104 $ 370,070 Year Ended December 31, 2016 2015 2014 Depreciation and amortization of property and equipment: (In thousands) Truckload $ 125,611 $ 121,144 $ 113,875 Dedicated 68,090 62,221 53,682 Swift Refrigerated 16,737 16,160 12,510 Intermodal 11,839 13,723 10,875 Subtotal 222,277 213,248 190,942 Non-reportable segments 44,857 38,487 30,180 Consolidated depreciation and amortization of property and equipment $ 267,134 $ 251,735 $ 221,122

Quarterly Result of Operation58

Quarterly Result of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]
Quarterly Results of Operations (Unaudited)	In management's opinion, the following summarized financial information fairly presents the Company's results of operations for the quarters noted. These results are not necessarily indicative of future quarterly results. First Quarter Second Quarter Third Quarter Fourth Quarter (In thousands, except per share data) 2016 Operating revenue $ 967,823 $ 1,011,854 $ 1,013,226 $ 1,038,614 Operating income 52,483 74,205 39,853 75,471 Net income 31,905 42,896 24,024 50,442 Basic earnings per share 0.23 0.32 0.18 0.38 Diluted earnings per share 0.23 0.32 0.18 0.38 2015 Operating revenue $ 1,015,144 $ 1,059,404 $ 1,064,973 $ 1,089,801 Operating income 75,000 98,476 74,921 121,707 Net income 37,840 50,954 36,281 72,502 Basic earnings per share 0.27 0.36 0.25 0.52 Diluted earnings per share 0.26 0.35 0.25 0.51

Introduction and Basis of Pre59

Introduction and Basis of Presentation (Details)	12 Months Ended
	Dec. 31, 2016SegmentVehicle
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number Of Company Operated National Terminal Network And Tractor Fleet	18,366
Number Of Tractors Driven By Company Drivers	13,937
Number Of Owner Operator Tractors	4,429
Number Of Fleet Of Trailers	64,066
Number Of Intermodal Containers	9,131
Number of Reportable Segments | Segment	4

Introduction and Basis of Pre60

Introduction and Basis of Presentation Change in Accounting Estimate (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended								12 Months Ended
	Oct. 31, 2016	Aug. 31, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in Accounting Estimate [Line Items]
Basic earnings per share			$ 0.38	$ 0.18	$ 0.32	$ 0.23	$ 0.52	$ 0.25	$ 0.36	$ 0.27	$ 1.11	$ 1.39	$ 1.14
Diluted earnings per share			$ 0.38	$ 0.18	$ 0.32	$ 0.23	$ 0.51	$ 0.25	$ 0.35	$ 0.26	$ 1.10	$ 1.38	$ 1.12
Salvage Value [Member]
Change in Accounting Estimate [Line Items]
Change in Accounting Estimate, Description	the Company changed its estimated residual values on certain trailers. This accelerated the depreciation on some trailers, while decelerating the depreciation on others. Management prospectively accounted for this as a change in accounting estimate. The impact on "Depreciation and amortization of property and equipment" was a decrease	the Company decreased the estimated residual values of a certain group of its tractors, as a result of recent trends in the used tractor market.  Management prospectively accounted for this as a change in accounting estimate.  This change increased "Depreciation and amortization of property and equipment" in the consolidated income statements
Depreciation	$ 0.6										$ (9)
Basic earnings per share											$ 0.05
Diluted earnings per share											$ 0.05

Introduction and Basis of Pre61

Introduction and Basis of Presentation Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Recently Issued Accounting Pronouncements [Line Items]
Other assets	$ 21,953	$ 26,585
Current portion of long-term debt	8,459	35,514
Long-term debt, less current portion	493,346	643,663
Accounts receivable securitization	$ 279,285	223,927
Accounting Standards Update 2015-03 [Member]
Recently Issued Accounting Pronouncements [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description	ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs, which amended ASC Subtopic 835-30, Interest – Imputation of Interest. The amendments in this ASU simplify the presentation of debt issuance costs and align the presentation with debt discounts. Entities are required to present debt issuance costs within liabilities as a direct deduction from the face amount of the related debt, rather than as a deferred charge within assets.
New Accounting Pronouncement or Change in Accounting Principle, Description of Transition Method	retrospective application, with related disclosures for a change in accounting principle. For public business entities, the amendments in these ASUs were effective for financial statements issued for fiscal years beginning after December 15, 2015, and the interim periods within those fiscal years, with early adoption permitted.
accounting standards update 2015 15 [Member]
Recently Issued Accounting Pronouncements [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description	ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements – Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting (SEC Update), which also amended ASC Subtopic 835-30, Interest – Imputation of Interest. The SEC determined that ASU 2015-03 (discussed above) did not address costs related to line-of-credit arrangements. The amendments in ASU 2015-15 clarify that entities may defer and present debt issuance costs as an asset, and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement.
Scenario, Previously Reported [Member]
Recently Issued Accounting Pronouncements [Line Items]
Other assets		29,353
Current portion of long-term debt		35,582
Long-term debt, less current portion		645,290
Accounts receivable securitization		225,000
Restatement Adjustment [Member]
Recently Issued Accounting Pronouncements [Line Items]
Other assets		(2,768)
Current portion of long-term debt		(68)
Long-term debt, less current portion		(1,627)
Accounts receivable securitization		$ (1,073)

Summary of Significant Accoun62

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2016
Percentage Of Amortizable Goodwill And Intangible Asset	150.00%
Percentage Of Income Tax Positions Likely To Be Realized	50.00%
Minimum [Member] | Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life	3 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	2 years
Minimum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member] | Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life	20 years
Maximum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life	5 years
Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life	15 years

Recently Issued Accounting Pr63

Recently Issued Accounting Pronouncements (Details)	12 Months Ended
	Dec. 31, 2016
Accounting Standards Update 2017-04 [Member] [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU are intended to simplify subsequent measurement of goodwill. The key amendment in the ASU eliminates Step 2 from the goodwill impairment test, in which entities measured a goodwill impairment loss by comparing the implied fair value to the carrying amount of a reporting unit's goodwill. Instead, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value with the carrying amount of a reporting unit and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value.
Expected Adoption Date and Method	January 2020, prospective
Financial Statement Impact	Currently under evaluation; not expected to be material
Accounting Standards Update 2017-03 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU that are relevant to the Company pertain to disclosures around the impact that recently issued accounting standards will have on the financial statements of a registrant when such standards are adopted in a future period. The amendments in this ASU indicate that the SEC staff expects that if an entity cannot reasonably estimate the impact of an ASU on the financial statements, then the entity should consider additional qualitative disclosures to assist the reader in assessing the significance of the standard's impact on its financial statements.
Expected Adoption Date and Method	Immediate
Financial Statement Impact	None - The Company's policy on disclosing recently issued accounting pronouncements is aligned with the amendments in this ASU.
Accounting Standards Update 2016-18 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU require transfers between cash and equivalents and restricted cash and equivalents, as well as direct cash receipts into and cash payments made from restricted cash and equivalents to be explained in the statement of cash flows. Restricted cash and restricted cash equivalents are to be included in the beginning and ending cash and cash equivalent balance totals on the statement of cash flows.
Expected Adoption Date and Method	January 2018; Retrospective
Financial Statement Impact	Material impact in cash flow presentation to reclassify restricted cash to "net increase/decrease in cash, restricted cash, and equivalents," and adjust the beginning and ending balances.
Accounting Standards Update 2016-17 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	This ASU updates the consolidation guidance on how a reporting entity that is a single decision maker of a Variable Interest Entity ('VIE") should treat indirect interests in the entity held through related parties that are under common control when determining whether it is the primary beneficiary of the VIE. The primary beneficiary of a VIE is the reporting entity that has a controlling financial interest in a VIE and, therefore, consolidates the VIE. A reporting entity that has an indirect interest in a VIE if it has a direct interest in a related party that, in turn has a direct interest in the VIE.
Expected Adoption Date and Method	January 2017, Modified Retrospective
Financial Statement Impact	No financial statement impact. The Company is not the primary beneficiary of any of its related parties.
Accounting Standards Update 2016-16 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	This ASU states that entities should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs (as compared to current GAAP, which prohibits the recognition of current and deferred income taxes for intra-entity asset transfer until the asset has been sold to an outside party).
Expected Adoption Date and Method	January 2018, Modified Retrospective
Financial Statement Impact	Currently under evaluation; not expected to be material since the Company's fixed assets are not typically transferred between legal entities for consideration.
Accounting Standards Update 2016-15 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	This ASU has several amendments, which are designed to reduce existing diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The ASU addresses eight specific cash flow issues, of which the following are expected to be applicable to Swift: 1) debt prepayment and extinguishment costs, 2) proceeds from settlement of insurance claims, 3) proceeds from settlement of corporate-owned life insurance policies, 4) beneficial interests in securitization transactions, and 5) separately identifiable cash flows and application of the predominance principle.
Expected Adoption Date and Method	January 2018, Retrospective
Financial Statement Impact	Currently under evaluation; not expected to be material.
Accounting Standards Update 2016-13 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The purpose of this ASU is to amend the current incurred loss impairment methodology with a new methodology that reflects expected credit losses and requires a broader range of reasonable and supportable information to inform credit loss estimates. This is the final credit accounting standard, out of a series, with detailed guidance on the new loss reserve model, Current Expected Credit Loss ("CECL"). Among other provisions, the amendments in the ASU require a financial asset (or group of assets) measured at amortized cost basis to be presented at the net amount expected to be collected. Entities are no longer required to wait until a loss is probable to record it.
Expected Adoption Date and Method	January 2020, Adoption method varies by amendment
Financial Statement Impact	Currently under evaluation; not expected to be material.
Accounting Standards Update 2016-12 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU clarify certain aspects regarding the collectibility criterion, sales taxes collected from customers, noncash consideration, contract modifications, and completed contracts at transition. It additionally clarifies that retrospective application only requires disclosure of the accounting change effect on prior periods presented, not on the period of adoption.
Expected Adoption Date and Method	January 2018, Modified retrospective
Financial Statement Impact	Currently under evaluation (1)	[1]
Accounting Standards Update 2016-10 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU clarify the following two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance, while retaining the related principles for those areas. The amendments do not change the core principle of the guidance.
Expected Adoption Date and Method	January 2018, Modified retrospective
Financial Statement Impact	Currently under evaluation (1)	[1]
Accounting Standards Update 2016-08 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU are intended to improve the operability and understandability of the implementation guidance on principal versus agent considerations, but do not change the core principle of the guidance.
Expected Adoption Date and Method	January 2018, Modified retrospective
Financial Statement Impact	Currently under evaluation (1)	[1]
Accounting Standards Update 2016-09 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU are intended to simplify various aspects of accounting for stock-based compensation, including income tax consequences, classification of awards as equity or liability, as well as classification of activities within the statement of cash flows.
Expected Adoption Date and Method	January 2017, Adoption method varies by amendment
Financial Statement Impact	Expected to be material (2)	[2]
Accounting Standards Update 2016-02 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The new standard requires lessees to recognize assets and liabilities arising from both operating and financing leases on the balance sheet. Lessor accounting for leases is largely unaffected by the new guidance.
Expected Adoption Date and Method	January 2019, Modified retrospective
Financial Statement Impact	Currently under evaluation; expected to be material, but not yet quantifiable.
Accounting Standards Update 2016-01 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU address various aspects of recognition, measurement, presentation, and disclosure of financial instruments. They additionally establish ASC Topic 321 – Investments – Equity Securities, which applies to investments in equity securities and other ownership interests in an entity, including investments in partnerships, unincorporated joint ventures, and limited liability companies.
Expected Adoption Date and Method	January 2018, Modified retrospective
Financial Statement Impact	Not expected to be material.
Accounting Standards Update 2014-14 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	This ASU deferred the effective date of ASU 2014-09 (Topic 606) to annual reporting periods beginning after December 15, 2017.
Expected Adoption Date and Method	January 2018, Modified retrospective
Financial Statement Impact	Currently under evaluation (1)	[1]
Accounting Standards Update 2015-11 [Member]
Recently Issued Accounting Pronouncements [Line Items]
Description	The amendments in this ASU simplify subsequent measurement of inventory for all inventory measurement methods, except for last-in-first-out. Entities will be required to measure inventory at the lower of cost and net realizable value, instead of the previously issued guidance of lower of cost or market.
Expected Adoption Date and Method	January 2017, prospective
Financial Statement Impact	Not expected to be material. Due to the nature of the Company's inventory balances (spare parts, tires, fuel, and supplies), inventory is predominantly stated at cost.
[1]	Management is in the diagnostic phase of assessing the financial and business impacts of implementing ASC Topic 606, Revenue from Contracts with Customers, including identifying revenue sources within the Company's lines of business, reviewing a sample of contracts, and developing a preliminary assessment. Based upon these preliminary procedures, management anticipates that the following key considerations will impact the Company's accounting and reporting under the new standard: •identification of what constitutes a contract in Swift's business practices,•variability in individual contracts, such as customer-specific terms that may vary from the master agreement,•principal versus agent determinations,•timing of revenue recognition (for example, point-in-time versus over time and/or accelerated versus deferred),•single versus multiple performance obligations, •new/changed estimates and management judgments (for example, system estimation of in-transit accruals versus manual estimation), •disaggregation of revenue by category within segments, and•others.Management expects that there will also be changes in sales, contracting, accounting, reporting, tax, debt covenants, and other business processes, policies, and controls, as a result of implementing ASC Topic 606. The Company is currently underway with implementing a new ERP system, which will also affect the implementation process.Based on the information currently available from the diagnostic phase, management cannot yet determine the quantitative impact on the financial statements; however, the impact is expected to be immaterial (potentially with changes only to the timing of revenue recognition between reportable periods, as well as changes in the requirements for accounting policy and other new disclosures). The financial impact is expected to be quantifiable by the time the Company files its first Quarterly Report on Form 10-Q in 2017, at which time the Company will be transitioning into the design and planning phase of implementing ASC Topic 606. Since we are continuing to evaluate the impact of ASC Topic 606, our disclosures around our preliminary assessments are subject to change.
[2]	The amendments to ASC Topic 718, Compensation – Stock Compensation, that are expected to affect the Company are discussed below.•Accounting for Income Tax Benefits/Deficiencies: All excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) should be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity should also recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company will need to reclassify approximately $16.8 million in historical net tax benefit/deficiency amounts previously recorded within additional paid-in capital into retained earnings/accumulated deficit. Going forward, tax benefit/deficiency amounts will be recorded in net income.•Classification of Excess Tax Benefits on the Statement of Cash Flows: Excess tax benefits should be classified along with other income tax cash flows as an operating activity. Application is permitted to be prospective or retrospective.Current GAAP requires classification within cash flows from financing activities. The Company presents its statement of cash flows using the indirect method, which presents excess tax benefits within cash flows from financing activities and a corresponding offset within the net income reconciliation of cash flows from operating activities. As such, the Company will need to reclassify the excess tax benefit amounts out of cash flows from financing activities and into cash flows from operating activities, upon adoption. Management expects to apply these amendments retrospectively.•Forfeitures: An entity can make an entity-wide accounting policy election to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures when they occur. Modified retrospective application is required, by means of a cumulative-effect adjustment to equity. Upon adoption, the Company expects to transition to accounting for forfeitures when they occur. This would result in approximately a $2.5 million unfavorable cumulative-effect adjustment to retained earnings/accumulated deficit to catch-up the previously unrecognized stock-based compensation associated with historical assumed forfeiture rates. Going forward, forfeitures will be recorded as favorable adjustments to stock-based compensation as they occur.•Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-withholding purposes: Cash paid by an employer when directly withholding shares for tax-withholding purposes should be classified as a financing activity. Retrospective application is required.Beginning in 2016, the Company began allowing certain members of management to have shares withheld for taxes when their restricted stock awards and performance units vest. As such, upon adopting the amendments in this ASU, the Company will need to present the amounts out of cash flows from operating activities and into cash flows from financing activities for the periods presented. For 2016, the amount was approximately $0.5 million.

Recently Issued Accounting Pr64

Recently Issued Accounting Pronouncements, Prospective Adoption (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Item Effected [Line Items]
Stock-based compensation expense	$ 6,017	$ 6,525	$ 5,080
Accounting Standards Update 2016-09 [Member]
Item Effected [Line Items]
Cumulative Effect on Retained Earnings, Tax	16,800
Stock-based compensation expense	2,500
Payments Related to Tax Withholding for Share-based Compensation	$ 500

Restricted Investments (Detail)

Restricted Investments (Detail) $ in Thousands		12 Months Ended
		Dec. 31, 2016USD ($)Securities	Dec. 31, 2015USD ($)Securities
Schedule of Restricted Investments [Line Items]
Cost or Amortized Cost	[1]	$ 22,717	$ 23,215
Estimated Fair Value	[1]	$ 22,688	$ 23,190
Restricted held to maturity investments		1 year
Securities with unrealized losses for less than 12 months | Securities		42	36
Duration of securities in unrealized loss position		12 months
United States corporate securities
Schedule of Restricted Investments [Line Items]
Cost or Amortized Cost		$ 16,432	$ 16,686
Gross Unrealized, Gains		0	2
Gross Unrealized, Temporary Losses		(23)	(27)
Estimated Fair Value		16,409	16,661
Municipal bonds
Schedule of Restricted Investments [Line Items]
Cost or Amortized Cost		4,760	4,904
Gross Unrealized, Gains		0	1
Gross Unrealized, Temporary Losses		(6)	(1)
Estimated Fair Value		4,754	4,904
Negotiable certificate of deposits
Schedule of Restricted Investments [Line Items]
Cost or Amortized Cost		1,525	1,625
Gross Unrealized, Gains		0	0
Gross Unrealized, Temporary Losses		0	0
Estimated Fair Value		1,525	1,625
Restricted investments, held to maturity
Schedule of Restricted Investments [Line Items]
Cost or Amortized Cost		22,717	23,215
Gross Unrealized, Gains		0	3
Gross Unrealized, Temporary Losses		(29)	(28)
Estimated Fair Value		$ 22,688	$ 23,190
[1]	Restricted investments are included in "Restricted investments, held to maturity, amortized cost."

Accounts Receivable, net (Sched

Accounts Receivable, net (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable, gross	$ 425,042	$ 440,349
Less: Allowance for doubtful accounts	(16,449)	(17,928)	$ (9,924)	$ (7,504)
Accounts receivable, net	408,593	422,421
Trade Customers [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable, gross	404,556	415,219
Equipment Manufacturers [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable, gross	4,755	6,801
Other [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable, gross	$ 15,731	$ 18,329

Accounts Receivable, net (Sch67

Accounts Receivable, net (Schedule Of Allowance For Doubtful Accounts) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Beginning balance	$ 17,928	$ 9,924	$ 7,504
Provision (Reduction)	(1,147)	8,004	2,844
Recoveries	332	0	89
Write-offs	0	0	(513)
Ending balance	$ 16,449	$ 17,928	$ 9,924

Assets Held for Sale (Schedule

Assets Held for Sale (Schedule Of Assets Held For Sale) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale	$ 6,969	$ 9,084
Land And Facilities [Member]
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale	288	288
Revenue Equipment [Member]
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale	$ 6,681	$ 8,796

Assets Held for Sale (Narrative

Assets Held for Sale (Narrative) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)property	Dec. 31, 2015USD ($)property	Dec. 31, 2014USD ($)property
Property, Plant and Equipment Assets Held-for-sale Disclosure [Abstract]
Period of time assets are expected to be sold, months	12 months
Number of properties sold | property	0	0	5
Disposal Group, Including Discontinued Operation, Assets			$ 14,500
Gain on sale of real property	$ 0	$ 0	$ 3,018

Notes Receivable (Details)

Notes Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 10,253	$ 15,749
Less: current portion of notes receivable	(6,961)	(9,817)
Notes receivable, less current portion	3,292	5,932
Owner Operator Relationship [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	10,253	15,725
Other Relationship [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 0	$ 24

Goodwill and Other Intangible71

Goodwill and Other Intangible Assets Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Gross Carrying Amount	$ 507,740	$ 507,740
Accumulated Impairment Losses	(254,484)	(254,484)
Net Carrying Amount	253,256	253,256
Goodwill, Impairment Loss	0	0	$ 0
Truckload goodwill
Goodwill [Line Items]
Gross Carrying Amount	376,998	376,998
Accumulated Impairment Losses	(190,394)	(190,394)
Net Carrying Amount	186,604	186,604
Dedicated goodwill
Goodwill [Line Items]
Gross Carrying Amount	130,742	130,742
Accumulated Impairment Losses	(64,090)	(64,090)
Net Carrying Amount	$ 66,652	$ 66,652

Goodwill and Other Intangible72

Goodwill and Other Intangible Assets Schedule of Intangible Assets, net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Customer Relationships:
Gross carrying value	$ 275,324	$ 275,324
Accumulated amortization	(190,056)	(173,242)
Customer relationships, net	85,268	102,082
Trade Name:
Gross carrying value	181,037	181,037
Intangible assets, net	$ 266,305	$ 283,119

Goodwill and Other Intangible73

Goodwill and Other Intangible Assets Finite-lived Intangible Assets Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2007
Schedule of Finite-Lived Intangible Assets Amortization Expense [Line Items]
Gross carrying value	$ 275,324	$ 275,324
Amortization of Intangible Assets	16,814	16,814	$ 16,814
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	16,800
Finite-Lived Intangible Assets, Amortization Expense, Year Two	16,300
Finite-Lived Intangible Assets, Amortization Expense, Year Three	15,600
Finite-Lived Intangible Assets, Amortization Expense, Year Four	15,600
Finite-Lived Intangible Assets, Amortization Expense, Year Five	15,600
Amortizations of intangible assets related to the 2007 Transactions
Schedule of Finite-Lived Intangible Assets Amortization Expense [Line Items]
Gross carrying value				$ 261,200
Amortization of Intangible Assets	15,648	15,648	15,648
Amortization related to intangible assets existing prior to the 2007 Transactions
Schedule of Finite-Lived Intangible Assets Amortization Expense [Line Items]
Amortization of Intangible Assets	1,166	$ 1,166	$ 1,166
Finite-Lived Intangible Assets, Amortization Expense, Year Two	$ 700

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities [Abstract]
Employee compensation	[1]	$ 51,217	$ 55,750
Owner-operator lease purchase reserve		6,229	5,271
Income tax accrual		5,119	2,043
Accrued owner-operator expenses		6,333	6,711
Deferred revenue		2,111	1,740
Fuel and property taxes		6,160	4,076
Accrued interest expense		1,819	1,532
Accrued legal	[2]	28,778	2,701
Other (2)(3)	[2],[3]	24,946	17,489
Accrued liabilities		$ 132,712	$ 97,313
Defined Benefit Plan Eligible Age For Employee			21 years
Defined Benefit Plan Employee Eligibility Criteria One		6 months
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		3.00%
Defined Contribution Plan Employer Contribution Vesting Period		5 years
Defined Contribution Plan, Cost Recognized		$ 5,700	$ 5,600	$ 4,700
Defined Benefit Pension Plan, Liabilities		$ 6,100	$ 5,900
[1]	The Company maintains a 401(k) benefit plan available to all employees who are 21 years of age or older and have completed six months of service. Under the plan, the Company has the option to match employee discretionary contributions up to 3% of an employee's compensation. Employees' rights to employer contributions vest after five years from their date of employment.For the years ended December 31, 2016, 2015, and 2014, the Company's employee benefits expense for matching contributions, included in "Salaries, wages, and employee benefits" in the consolidated income statements, was approximately $5.7 million, $5.6 million, and $4.7 million, respectively. As of December 31, 2016 and 2015, the balance includes $6.1 million and $5.9 million in matching contributions, respectively, to the plan in respect of such matching contributions.
[2]	The Company has disaggregated "Accrued legal" from "Other" as of December 31, 2016, and retrospectively adjusted the presentation as of December 31, 2015 for comparative purposes. See Note 17 for further details regarding the Company's legal accruals.
[3]	Includes the current portion of accrued consulting fees for Jerry Moyes. See Note 23 for further details.

Claims Accruals (Details)

Claims Accruals (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2015USD ($)$ / insurance_claim	Dec. 31, 2016USD ($)
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals		$ 233,710	$ 246,592
Less: current portion of claims accruals		(84,429)	(80,866)
Claims accruals, less current portion		$ 149,281	165,726
Group Medical Specific Deductible | $ / insurance_claim		500,000
Group Medical Aggregating Individual Deductible | $ / insurance_claim		150,000
Auto and collision liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals		$ 123,086	128,643
Workers' compensation liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals		92,608	101,232
Owner-operator claims liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals		12,304	11,736
Cargo damage liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals		5,348	4,695
Other liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Claims accruals	[1]	$ 364	$ 286
[1]	Includes group medical liability. Effective January 1, 2015, the Company is fully insured on its group medical benefits, subject to contributed premiums. Prior to January 1, 2015, the Company had a $500 thousand specific deductible with an aggregating individual deductible of $150 thousand of each employee health care claim, as well as commercial insurance for the balance.

Income Taxes (Income Tax Expens

Income Taxes (Income Tax Expense (Benefit) ) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current expense:
Federal	$ 88,689	$ 76,737	$ 81,117
State	10,610	8,826	8,861
Foreign	3,053	8,783	4,107
Current expense (benefit), Total	102,352	94,346	94,085
Deferred (benefit) expense:
Federal	(31,380)	24,097	(4,189)
State	(211)	3,419	1,975
Foreign	(5,059)	(2,653)	(2,397)
Deferred expense (benefit), Total	(36,650)	24,863	(4,611)
Income tax expense	$ 65,702	$ 119,209	$ 89,474

Income Taxes (Schedule Of Effec

Income Taxes (Schedule Of Effective Income Tax Rate Reconciliation) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income tax rate reconciliation [Line Items]
Effective Income Tax Rate Reconciliation, Percent	30.60%		37.60%	35.70%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%		35.00%	35.00%
Computed expected tax expense	$ 75,239		$ 110,875	$ 87,719
Increase (decrease) in income taxes resulting from:
State income taxes, net of federal income tax benefit	6,443		8,745	6,866
Domestic Productions Activities Deduction	(7,777)	[1]	0	0
Toll Roads income tax credit	4,082	[2]	0	0
Other	(4,121)		(411)	(5,111)
Income tax expense	65,702		119,209	89,474
Software Development [Member]
Increase (decrease) in income taxes resulting from:
Domestic Productions Activities Deduction	(2,200)		(2,200)	(2,200)	$ (1,200)
Income tax deduction			6,200	$ 6,400	$ 3,400
Trans Mex [Member]
Increase (decrease) in income taxes resulting from:
Toll Roads income tax credit	$ 1,800		2,300
Toll roads income tax credit [Member]
Increase (decrease) in income taxes resulting from:
tax credit allowance	50.00%
Income Tax Credits and Adjustments	$ 5,600		$ 6,500
[1]	Domestic Production Activities Deduction — Internal Revenue Code Section 199 permits taxpayers to claim a deduction from taxable income attributable to certain domestic production activities such as the development of computer software and the manufacturing of goods. Beginning in 2010 and thereafter, the deduction is equal to 9% of the smaller of a taxpayer’s qualified production activities or taxable income. Due to its increased software development efforts, the Company has elected to take the deduction in the current year and preceding open tax years. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to a domestic production activities deduction on the Company's 2015 federal tax return. The Company also received tax benefits for years ending December 31, 2016, December 31, 2014, and December 31, 2013. The Company generated $6.4 million, $6.2 million, $6.2 million, and $3.4 million in domestic production activities deductions for the development of computer software in 2016, 2015, 2014, and 2013, respectively. This resulted in approximately $2.2 million, $2.2 million, $2.2 million, and $1.2 million in tax benefits in 2016, 2015, 2014, and 2013, respectively.
[2]	Toll roads income tax credit — Trans-Mex, our Mexico trucking subsidiary, qualified for an income tax credit equal to 50% of the qualified tolls paid. The decrease in the effective tax rate for the year ended December 31, 2016 was partially attributable to the toll road income tax credit reported on the 2015 income tax return. Trans-Mex also will claim a toll road income tax credit for 2016. Trans-Mex paid $5.6 million and $6.5 million in qualifying tolls during 2016 and 2015, respectively. This resulted in approximately $1.8 million and $2.3 million in tax benefits in 2016 and 2015, respectively.

Income Taxes (Components Of Net

Income Taxes (Components Of Net Deferred Tax Asset (Liability) ) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Self-insurance accruals	$ 73,654	$ 66,949
Allowance for doubtful accounts	8,036	11,448
Amortization of stock options	6,397	8,923
Accrued liabilities	15,366	1,773
Vacation accrual	5,358	4,990
Other	8,940	11,589
Total deferred tax assets	117,751	105,672
Valuation allowance	0	0
Total deferred tax assets, net	117,751	105,672
Deferred tax liabilities:
Property and equipment, principally due to differences in depreciation	(420,975)	(434,802)
Prepaid taxes, licenses and permits deducted for tax purposes	(13,284)	(14,083)
Cancellation of debt	(3,747)	(5,622)
Intangible assets	(106,143)	(110,546)
Other	(1,324)	(4,451)
Deferred tax liabilities	(545,473)	(569,504)
Deferred income taxes	$ (427,722)	$ (463,832)

Income Taxes (Reconciliation Of

Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of year	$ 1,739	$ 1,739	$ 2,385
Increases for tax positions taken prior to beginning of year	0	0	95
Decreases for tax positions taken prior to beginning of year	(975)	0	(741)
Unrecognized tax benefits at end of year	$ 764	$ 1,739	$ 1,739

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Tax Credit Carryforward [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Federal	$ 0.5
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	0.1
Income Tax Examination, Increase (Decrease) in Liability from Prior Year	0	$ 0
Income Tax Examination, Penalties and Interest Expense	$ 0	$ 0
Minimum [Member]
Tax Credit Carryforward [Line Items]
Federal and State Operating Loss Carryforwards, Expiration Date	Jan. 1, 2017
Maximum [Member]
Tax Credit Carryforward [Line Items]
Federal and State Operating Loss Carryforwards, Expiration Date	Dec. 31, 2030

Income Taxes Income Taxes Other

Income Taxes Income Taxes Other (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Cumulative Undistributed Earnings Of Foreign Subsidiaries	$ 36.3
Income Tax Examination [Line Items]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 0.4	$ 1.4
Minimum [Member]
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,012
Open Tax Year	2,012
Maximum [Member]
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,015

Accounts Receivable Securitiz82

Accounts Receivable Securitization (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Accounts Receivable Securitization [Line Items]
Debt Instrument, Collateral Fee		$ 4,400	$ 3,500	$ 3,500
2015 RSA [Member]
Schedule of Accounts Receivable Securitization [Line Items]
Borrowing capacity	[1]	$ 400,000
Final maturity date		Jan. 10, 2019
Unused commitment fee rate		35 basis points
Program fees on outstanding balances		one-month LIBOR + 90 basis points
Program fees on outstanding balances, base rate		0.90%
Accordion Option Accounts Receivable Securitization		$ 75,000
Debt Instrument, Interest Rate During Period		1.30%
2013 RSA [Member]
Schedule of Accounts Receivable Securitization [Line Items]
Borrowing capacity		$ 375,000
Final maturity date		Jul. 13, 2016
Unused commitment fee rate		35 basis points
Program fees on outstanding balances		one-month LIBOR + 95 basis points
Program fees on outstanding balances, base rate		0.95%
Accordion Option Accounts Receivable Securitization			$ 50,000
Debt Instrument, Interest Rate During Period			1.00%
[1]	The 2015 RSA has an accordion option to increase the maximum borrowing capacity by up to an additional $75.0 million, subject to participation by the Purchasers. The 2013 RSA borrowing capacity included a $50.0 million accordion option, which was exercised in September 2014.

Debt And Financing Schedule of

Debt And Financing Schedule of Debt Balances by Instrument (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt		$ 501,805	$ 679,177
Less: current portion of long-term debt		(8,459)	(35,514)
Long-term debt, less current portion		493,346	643,663
Revolving line of credit	[1]	130,000	200,000
Long-term debt, including revolving line of credit		631,805	879,177
Letters of Credit Outstanding, Amount		97,000	95,000
Debt Issuance Costs, Net		3,222	4,264
Debt Issuance Costs, Current, Net		0	68
2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Long-term debt	[2],[3]	492,912	668,055
Debt Issuance Costs, Net		1,338	1,695
Other
Debt Instrument [Line Items]
Long-term debt		$ 8,893	$ 11,122
[1]	The Company also had outstanding letters of credit under the New Revolver, primarily related to workers' compensation and self-insurance liabilities of $97.0 million at December 31, 2016 and $95.0 million at December 31, 2015.
[2]	Refer to Note 21 for information regarding the fair value of debt.
[3]	The New Term Loan A is included in "Current portion of long-term debt" and "Long-term debt, less current portion." Carrying value is net of $1.3 million and $1.7 million DLCs as of December 31, 2016 and 2015, respectively.

Debt And Financing Schedule o84

Debt And Financing Schedule of Debt Terms (Details) - USD ($)		Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2016	Dec. 31, 2015		Jun. 30, 2020	Jul. 27, 2015	Dec. 31, 2014
2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 680,000,000			$ 680,000,000
Final maturity date					Jul. 27, 2020
Interest rate base					LIBOR
LIBOR floor					0.00%
Minimum principal payment — amount	[1]				$ 6,625,000
Minimum principal payment — frequency					Quarterly
Minimum principal payment — commencement date	[1]				Dec. 31, 2015
Debt Instrument, Interest Rate During Period		2.18%	2.12%
2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 600,000,000			$ 600,000,000
Final maturity date					Jul. 27, 2020
Interest rate base					LIBOR
LIBOR floor					0.00%
Minimum principal payment — amount	[1]				$ 0
Minimum principal payment — frequency					Once
Minimum principal payment — commencement date	[1]				Jul. 27, 2020
Debt Instrument, Interest Rate During Period		2.18%	2.08%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.25%	0.25%
Line of Credit Facility, Commitment Fee Percentage		1.50%	1.75%
2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 500,000,000			$ 500,000,000			$ 500,000,000
Final maturity date						Jun. 9, 2019
Interest rate base						LIBOR
LIBOR floor						0.00%
Minimum principal payment — amount	[2]					$ 5,625,000
Minimum principal payment — frequency						Quarterly
Minimum principal payment — commencement date	[2]					Mar. 31, 2015
2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity			400,000,000			$ 400,000,000			400,000,000
Final maturity date						Jun. 9, 2021
Interest rate base						LIBOR
LIBOR floor						0.75%
Minimum principal payment — amount						$ 1,000,000
Minimum principal payment — frequency						Quarterly
Minimum principal payment — commencement date						Jun. 30, 2014
2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 450,000,000			$ 450,000,000			$ 450,000,000
Final maturity date						Jun. 9, 2019
Interest rate base						LIBOR
LIBOR floor						0.00%
Minimum principal payment — amount						$ 0
Minimum principal payment — frequency						Once
Minimum principal payment — commencement date						Jun. 30, 2019
Minimum [Member] | 2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]	1.50%			1.50%
Minimum [Member] | 2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]	1.50%			1.50%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage					0.25%
Minimum [Member] | 2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin			1.50%	[3]		1.50%	[3]			1.50%
Minimum [Member] | 2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Interest rate margin		2.75%	3.00%	[3]	2.75%	3.00%	[3]
Minimum [Member] | 2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]		1.50%			1.50%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage						0.25%
Maximum [Member] | 2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]	2.25%			2.25%
Maximum [Member] | 2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[4]	2.25%			2.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage					0.35%
Maximum [Member] | 2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin			2.25%	[3]		2.25%	[3]			2.25%
Maximum [Member] | 2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Interest rate margin		3.00%	3.00%	[3]	3.00%	3.00%	[3]
Maximum [Member] | 2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]		2.25%			2.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage						0.35%
Subsequent Event [Member] | 2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Minimum principal payment — amount								$ 12,300,000
Subsequent Event [Member] | 2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Minimum principal payment — amount								$ 11,300,000
[1]	Commencing in March 2017, the minimum required quarterly payment on the New Term Loan A is $12.3 million, at which it would remain until final maturity. However, as of January 2017, the Company voluntarily prepaid all minimum quarterly principal payments through final maturity.
[2]	Commencing in March 2017, the minimum principal payment amount on the Old Term Loan A would have been $11.3 million.
[3]	The interest rate margin for the New Term Loan A and New Revolver is based on the Company's consolidated leverage ratio. As of December 31, 2016, interest accrued at 2.18% on the New Term Loan A and 2.18% on the New Revolver. As of December 31, 2015, interest accrued at 2.12% on the New Term Loan A and 2.08% on the New Revolver.
[4]	The commitment fee for the unused portion of the New Revolver is based on the Company's consolidated leverage ratio, and ranges from 0.25% to 0.35%. As of December 31, 2016, commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.50%. As of December 31, 2015, commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.75%.

Debt And Financing (Narrative)

Debt And Financing (Narrative) (Details) - USD ($)		Jul. 27, 2015	Nov. 30, 2014	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014	Jun. 09, 2014
Debt Instrument [Line Items]
Proceeds from long-term debt							$ 0	$ 684,504,000		$ 900,000,000
Net (repayments) borrowings on revolving line of credit							(70,000,000)	143,000,000		40,000,000
Repayments of Long-term Debt		$ 4,900,000
Long-term Debt							501,805,000	679,177,000
Loss on debt extinguishment							0	9,567,000		$ 39,909,000
2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		450,000,000						450,000,000
Extinguishment of Debt, Amount		0
Proceeds from long-term debt					$ 164,000,000
2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		500,000,000						500,000,000
Extinguishment of Debt, Amount		485,000,000
Proceeds from long-term debt				$ 450,000,000	$ 50,000,000
2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		400,000,000						400,000,000
Extinguishment of Debt, Amount		395,000,000
2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity							680,000,000
Proceeds from long-term debt		680,000,000
Long-term Debt	[1],[2]						492,912,000	$ 668,055,000
2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 600,000,000
Net (repayments) borrowings on revolving line of credit		$ 200,000,000
First Lien Term Loan B 1 [Member]
Debt Instrument [Line Items]
Long-term Debt											$ 229,000,000
First Lien Term Loan B 2 [Member]
Debt Instrument [Line Items]
Long-term Debt											$ 370,900,000
Senior Second Priority Secured Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount			$ 428,100,000			$ 71,900,000
Debt Instrument, Redemption Price, Percentage			105.00%			105.58%
Interest rate margin			10.00%
Debt Instrument, Face Amount			$ 500,000,000
Minimum [Member] | 2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]							1.50%
Minimum [Member] | 2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin								1.50%	[3]	1.50%
Minimum [Member] | 2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Interest rate margin							2.75%	3.00%	[3]
Minimum [Member] | 2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]						1.50%
Minimum [Member] | 2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]						1.50%
Maximum [Member] | 2014 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]							2.25%
Maximum [Member] | 2014 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin								2.25%	[3]	2.25%
Maximum [Member] | 2014 Agreement, Term Loan B [Member]
Debt Instrument [Line Items]
Interest rate margin							3.00%	3.00%	[3]
Maximum [Member] | 2015 Agreement, Term Loan A [Member]
Debt Instrument [Line Items]
Interest rate margin	[3]						2.25%
Maximum [Member] | 2015 Agreement, Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate margin	[4]						2.25%
[1]	Refer to Note 21 for information regarding the fair value of debt.
[2]	The New Term Loan A is included in "Current portion of long-term debt" and "Long-term debt, less current portion." Carrying value is net of $1.3 million and $1.7 million DLCs as of December 31, 2016 and 2015, respectively.
[3]	The interest rate margin for the New Term Loan A and New Revolver is based on the Company's consolidated leverage ratio. As of December 31, 2016, interest accrued at 2.18% on the New Term Loan A and 2.18% on the New Revolver. As of December 31, 2015, interest accrued at 2.12% on the New Term Loan A and 2.08% on the New Revolver.
[4]	The commitment fee for the unused portion of the New Revolver is based on the Company's consolidated leverage ratio, and ranges from 0.25% to 0.35%. As of December 31, 2016, commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.50%. As of December 31, 2015, commitment fees on the unused portion of the New Revolver accrued at 0.25% and outstanding letter of credit fees accrued at 1.75%.

Deferred Loan Costs (Details)

Deferred Loan Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Issuance Costs [Line Items]
DLCs	$ 3,222	$ 4,264
Other assets
Debt Issuance Costs [Line Items]
DLCs	1,169	1,496
Current portion of long-term debt
Debt Issuance Costs [Line Items]
DLCs	0	68
Long-term debt, less current portion
Debt Issuance Costs [Line Items]
DLCs	1,338	1,627
Accounts receivable securitization
Debt Issuance Costs [Line Items]
DLCs	$ 715	$ 1,073

Leases (Detail)

Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Leases, Capital [Abstract]
Capital Leases, Net Investment in Direct Financing Leases	$ 319,800	$ 357,800
Accumulated amortization	97,000	90,100
Rental expense	226,258	240,501	$ 229,290
Non Cancelable Operating Leases, Future Minimum Payments Due [Abstract]
2,017	203,463
2,018	144,205
2,019	92,065
2,020	44,592
2,021	23,231
Thereafter	48,813
Future minimum lease payments	556,369
Non Cancelable Capital Leases, Future Minimum Payments Due
2,017	77,925
2,018	49,965
2,019	60,212
2,020	13,669
2,021	29,890
Thereafter	17,268
Future minimum lease payments	248,929
Less: amounts representing interest	(14,993)
Present value of minimum lease payments	233,936
Less: current portion	(72,473)	(59,794)
Capital lease obligations, long-term	161,463	$ 222,001
Operating Leases as Lessor [Abstract]
2,017	109,077
2,018	64,615
2,019	27,739
2,020	9,752
2,021	9
Thereafter	0
Future minimum lease payments receivable	$ 211,192

Purchase Commitments (Details)

Purchase Commitments (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Long-term Purchase Commitment [Line Items]
Percentage of options lapsed to cancel tractor purchase orders	28.60%
Minimum [Member]
Long-term Purchase Commitment [Line Items]
Option to cancel tractor purchase orders	60 days
Maximum [Member]
Long-term Purchase Commitment [Line Items]
Option to cancel tractor purchase orders	90 days
Capital Addition Purchase Commitments [Member]
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Due in Next Twelve Months	$ 270.7
Purchase Obligation, Due in Second and Third Year	0
Capital Addition Purchase Commitments of Tractors [Member]
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Due in Next Twelve Months	265.3
Non revenue equipment purchase commitments [Member]
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Due in Next Twelve Months	13.6
Purchase Obligation, Due in Second and Third Year	8.8
Purchase Obligation, Due in Fourth and Fifth Year	$ 3.9

Contingencies and Legal Proce89

Contingencies and Legal Proceedings (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)plaintiff
Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual	$ 1
Loss Contingency, Inestimable Loss	For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made.
Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual	$ 25
Loss Contingency, Inestimable Loss	For certain matters, it is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated. For those matters, no accrual has been made.
Employee Hiring Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual	$ 0
Loss Contingency, Inestimable Loss	It is not probable that a loss was incurred and/or the amount of loss cannot be reasonably estimated for these matters.
Other environmental [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 0.6
Minimum [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	0
Minimum [Member] | Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	0
Minimum [Member] | Employee Hiring Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	0
Maximum [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	0.3
Maximum [Member] | Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	44
Maximum [Member] | Employee Hiring Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	$ 0
California Private Attorneys General Act Class Action [Member] | Employee Compensation and Pay Practices Matters [Member] | California Private Attorney General Act Class Action [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiff alleges that the Company violated California law by failing to timely pay wages and failing to reimburse employees for business expenses.
Loss Contingency, Name of Plaintiff	Theron Christopher (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	July 8, 2016
Loss Contingency, Domicile of Litigation	Superior Court of California, County of Riverside
Loss Contingency, Opinion of Counsel	The PAGA matter is in its initial phases and is expected to move into discovery. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiffs generally allege one or more of the following: that the Company 1) failed to pay the California minimum wage; 2) failed to provide proper meal and rest periods; 3) failed to timely pay wages upon separation from employment; 4) failed to pay for all hours worked; 5) failed to pay overtime; 6) failed to properly reimburse work-related expenses; and 7) failed to provide accurate wage statements.
Loss Contingency, Opinion of Counsel	Before and during 2016, the Rudsell, Peck, Peck PAGA, Mares, McKinsty, and Nilsen complaints were stayed, pending resolution of earlier-filed cases. In May 2016, the Burnell plaintiffs were denied class certification. Their subsequent petition to appeal the decertification order was also denied. Following the Burnell plaintiffs' failure to certify the class, the stays on certain cases were lifted. Those cases are now in discovery. Based on the current procedural nature of the cases, the final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal And Rest Employee Class Action 1 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	John Burnell (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co., Inc
Loss Contingency, Lawsuit Filing Date	March 22, 2010
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal And Rest Employee Class Action 5 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	James R. Rudsell (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC and Swift Transportation Company
Loss Contingency, Lawsuit Filing Date	April 5, 2012
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal and Rest Employee Class Action 2 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Lawrence Peck (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	September 25, 2014
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal and Rest Employee Class Action 7 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Lawrence Peck (1)(2)	[1],[2]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC, et al.
Loss Contingency, Lawsuit Filing Date	November 20, 2014
Loss Contingency, Domicile of Litigation	Superior Court of California, County of Riverside
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal And Rest Employee Class Action 3 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Sadashiv Mares (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	February 27, 2015
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal And Rest Employee Class Action 4 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Rafael McKinsty(1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC, et al.
Loss Contingency, Lawsuit Filing Date	April 15, 2015
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Wage, Meal, and Rest: Driver Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage Meal And Rest Employee Class Action 6 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Thor Nilsen (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	October 15, 2015
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Meal, Wage, and Rest: Yard Hostler Class Action [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiffs, representing yard hostlers employed by the Company in California, generally allege one or more of the following: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime and doubletime wages required by California law; 3) failed to provide accurate, itemized wage statements; 4) failed to timely pay wages upon separation from employment; 5) failed to reimburse for business expenses; and 6) failed to provide proper meal and rest periods.
Loss Contingency, Opinion of Counsel	The Barker and Fritsch complaints are currently in discovery. The Company retains all of its defenses against liability and damages related to these lawsuits. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of these matters and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
California Meal, Wage, and Rest: Yard Hostler Class Action [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage, Meal and Rest Maintenance & Service Employees Class Action [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Grant Fritsch (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Company of Arizona, LLC and Swift Transportation Company
Loss Contingency, Lawsuit Filing Date	January 28, 2016
Loss Contingency, Domicile of Litigation	Superior Court of California, County of San Bernardino
California Meal, Wage, and Rest: Yard Hostler Class Action [Member] | Employee Compensation and Pay Practices Matters [Member] | California Wage, Meal, and Rest: Yard Hostler Class Action 2 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Bill Barker, Tab Bachman, and William Yingling (1)
Loss Contingency, Name of Defendant	Swift Transportation Company of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	April 1, 2016
Loss Contingency, Domicile of Litigation	United States District Court for the Eastern District of California
National Customer Service Misclassification Class Actions [Member]
Loss Contingencies [Line Items]
Loss Contingency, Opinion of Counsel	Castro, along with five other former Customer Service Representative IV employees opted into this collective action lawsuit, which was being pursued under the FLSA. In addition to the Castro collective action, thirteen Customer Service Representative IV employees pursued similar claims in individual arbitrations. The parties conducted three arbitrations regarding the individual claimants. The parties agreed to mediation, which was held in January 2017. The parties are currently finalizing a global settlement of the collective action and the individual arbitrations.
National Customer Service Misclassification Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiff, a former Customer Service Representative IV, alleges that the Company failed to pay overtime under the FLSA. Additionally, with respect to California state law, the plaintiff alleges that the Company: 1) failed to pay overtime; 2) failed to pay timely final wages; 3) failed to provide meal and rest periods; and 4) violated the unfair competition law.
National Customer Service Misclassification Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | National Customer Service Misclassification Class Action 2 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Salvador Castro (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Co. of Arizona, LLC
Loss Contingency, Lawsuit Filing Date	May 11, 2016
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
Arizona Fair Labor Standards Act Class Actions [Member]
Loss Contingencies [Line Items]
Loss Contingency, Opinion of Counsel	In March 2016, the Company filed a motion to dismiss the plaintiff's overtime claims, which was granted by the district court in May 2016. The plaintiff recently filed a Motion for Conditional Class Certification, which the Company intends to oppose. The Company retains all of its defenses against liability and damages for the remaining claims. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
Arizona Fair Labor Standards Act Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiff alleges that the Company violated the FLSA by failing to pay its trainee drivers minimum wage for all work performed and by failing to pay overtime.
Arizona Fair Labor Standards Act Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | Delaware Fair Labor Standards Act Class Action [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Pamela Julian (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Inc., et al.
Loss Contingency, Lawsuit Filing Date	December 29, 2015
Loss Contingency, Domicile of Litigation	United States District Court for the District of Arizona
Washington Overtime Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiffs allege one or more of the following, pertaining to Washington state-based drivers: that the Company 1) failed to pay minimum wage; 2) failed to pay overtime; 3) failed to pay all wages due at established pay periods; 4) failed to provide proper meal and rest periods; 5) failed to provide accurate wage statements; and 6) unlawfully deducted from employee wages.
Loss Contingency, Opinion of Counsel	The parties in the Slack matter are finishing discovery and the next step will be for the parties to file dispositive motions. The case is scheduled for trial in September 2017. The Hedglin matter is currently in discovery. The Company retains all of its defenses against liability and damages for both matters. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
Washington Overtime Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | Washington Overtime Class Action [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Troy Slack (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation
Loss Contingency, Lawsuit Filing Date	September 9, 2011
Loss Contingency, Domicile of Litigation	United States District Court for the Western District of Washington
Washington Overtime Class Actions [Member] | Employee Compensation and Pay Practices Matters [Member] | Washington Overtime Class Action 2 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Julie Hedglin (1)	[1]
Loss Contingency, Name of Defendant	Swift Transportation Company of Arizona, LLC and Swift Transportation Corporation
Loss Contingency, Lawsuit Filing Date	January 14, 2016
Loss Contingency, Domicile of Litigation	United States District Court for the Western District of Washington
Arizona Owner-operator Class Actions [Member] | Arizona owner operator class action 1 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Leonel Garza (1)	[3]
Loss Contingency, Name of Defendant	Swift Transportation Co., Inc.
Loss Contingency, Lawsuit Filing Date	January 30, 2004
Loss Contingency, Domicile of Litigation	Arizona Supreme Court
Arizona Owner-operator Class Actions [Member] | Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The putative class alleges that the Company improperly compensated owner-operators (later expanding the class to include employee drivers) using the contracted and industry standard remuneration based upon dispatched miles, instead of using a method of calculating mileage that the plaintiffs allege would be more accurate.
Loss Contingency, Opinion of Counsel	The original trial court's decision was to deny class certification of the owner-operators, which was reversed and reinstated several times by various courts prior to 2016. The class is currently certified, based on an appellate court's decision from July 2016. The Company filed a petition for review with the Arizona Supreme Court in August 2016, which was denied in January 2017. The matter will now proceed in the Maricopa County Superior Court. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
Ninth Circuit Owner-operator Misclassification Class Actions [Member] | Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The putative class alleges that the Company misclassified owner-operators as independent contractors in violation of the FLSA and various state laws, and that such owner-operators should be considered employees. The lawsuit also raises certain related issues with respect to the lease agreements that certain owner-operators have entered into with IEL.
Loss Contingency, Opinion of Counsel	For several years, the parties have been arguing over the proper venue in which to proceed. The plaintiffs argue that they signed contracts of employment, thus exempting them from arbitration under the Federal Arbitration Act, and claim that their case should be heard in court by a judge. The Company takes the position that these individuals signed independent contractor agreements and therefore can properly be required to submit their claims to arbitration. In January 2017, the district court issued an order finding that the plaintiffs had signed contracts of employment and thus the case could properly proceed in court. The Company has appealed this decision to the Ninth Circuit and will seek to stay the district court case, pending resolution of the appeal. The Company intends to vigorously defend against any proceedings. The final disposition of the matter and impact to the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
Ninth Circuit Owner-operator Misclassification Class Actions [Member] | Owner-Operator Matters [Member] | Ninth circuit owner operator misclassification class action 1 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Joseph Sheer, Virginia Van Dusen, Jose Motolinia, Vickii Schwalm, Peter Wood (1)	[3]
Loss Contingency, Name of Defendant	Swift Transportation Co., Inc., Interstate Equipment Leasing, Inc., Jerry Moyes, and Chad Killebrew
Loss Contingency, Lawsuit Filing Date	December 22, 2009
Loss Contingency, Domicile of Litigation	Unites States District Court of Arizona and Ninth Circuit Court of Appeals
Utah Collective and Individual Arbitration [Member]
Loss Contingencies [Line Items]
Loss Contingency, Opinion of Counsel	In June 2016, mediation commenced, but there was ultimately no settlement of the matter. In October 2016, the arbitrator ruled that approximately 1,300 Central Refrigerated Service, Inc. drivers were misclassified as independent contractors, and should have been compensated as employees. The arbitrator ruled that damages could be assessed in a collective proceeding and declined to decertify the collective proceeding. Based on the October 2016 arbitration ruling, the Company increased its accrual related to this matter. A damages trial is scheduled for April 2017. No trial date on the claimants' damages has been set by the arbitrator. The Company and the Central Parties dispute the arbitrator's rulings to date and intend to continue to vigorously defend against the plaintiffs' claims in both the collective action and individual proceedings. The likelihood that a loss has been incurred is probable.
Utah Collective and Individual Arbitration [Member] | Owner-Operator Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiffs allege that the Central Parties (defined below) misclassified owner-operator drivers as independent contractors and were therefore liable to these drivers for minimum wages and other employee benefits under the FLSA. The complaint also alleges a federal forced labor claim under U.S.C. §1589 and §1595, as well as fraud and other state-law claims.
Utah Collective and Individual Arbitration [Member] | Owner-Operator Matters [Member] | Utah Collective And Individual Arbitration 1 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Gabriel Ciluffo, Kevin Shire, and Bryan Ratterree (1)(2)	[3],[4]
Loss Contingency, Name of Defendant	Central Refrigerated Service, Inc., Central Leasing, Inc., Jon Isaacson, and Jerry Moyes (the "Central Parties"), as well as Swift Transportation Company
Loss Contingency, Lawsuit Filing Date	June 1, 2012
Loss Contingency, Domicile of Litigation	American Arbitration Association
Loss Contingency, Number of Plaintiffs | plaintiff	325
Indiana Fair Credit Reporting Act Class Actions [Member] | Indiana Fair Credit Reporting Act Class Action Litigation [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Melvin Banks (1)	[5]
Loss Contingency, Name of Defendant	Central Refrigerated Service, Inc.
Loss Contingency, Lawsuit Filing Date	March 18, 2015
Loss Contingency, Domicile of Litigation	United States District Court for the District of Arizona
Indiana Fair Credit Reporting Act Class Actions [Member] | Employee Hiring Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiff alleges that Central Refrigerated Service, Inc. violated the Fair Credit Reporting Act by failing to provide job applicants with adverse action notices and copies of their consumer reports and statements of rights.
Loss Contingency, Opinion of Counsel	The first phase of discovery, regarding potential for identifying and certifying a class of affected job applicants, has been completed. The parties are currently completing a class certification briefing and the Company filed a Motion for Summary Judgment. The Company retains all of its defenses against liability and damages. Additionally, the Company intends to vigorously defend against the merits of the claims and to challenge certification. The final disposition of the matter and the impact on the Company cannot be determined at this time. The likelihood that a loss has been incurred is remote.
California Class and Collective Action for Pre-employment Physical Testing Actions [Member] | California Class and Collective Action for Pre-Employment Physical Testing [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff	Robin Anderson (1)	[5]
Loss Contingency, Name of Defendant	Central Refrigerated Service, Inc., Workwell Systems, Inc., and Swift Transportation Company
Loss Contingency, Lawsuit Filing Date	October 6, 2014
Loss Contingency, Domicile of Litigation	United States District Court for the Central District of California
California Class and Collective Action for Pre-employment Physical Testing Actions [Member] | Employee Hiring Practices Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency, Allegations	The plaintiff alleges that pre-employment tests of physical strength administered by a third party on behalf of Central Refrigerated Service, Inc. had an unlawfully discriminatory impact on female applicants and applicants over the age of 40. The suit seeks damages under Title VII of the Civil Rights Act of 1964, the age Discrimination Act, and parallel California state law provisions, including the California Fair Employment and Housing Act.
Loss Contingency, Opinion of Counsel	Litigation is at a very preliminary stage and no trial date has been set. There is no information available regarding the number of potential members of the putative class or collective actions. The Company intends to vigorously defend against the merits of the plaintiff's claims and to oppose certification of any class of plaintiffs. The final disposition of this case and the financial impact cannot be determined at this time. The likelihood that a loss has been incurred is remote.
[1]	Individually and on behalf of all others similarly situated.
[2]	Peck PAGA complaint.
[3]	Individually and on behalf of all others similarly situated.
[4]	In addition to the collective arbitration that is pending before the American Arbitration Association ("AAA"), the named plaintiffs, along with approximately 325 other owner-operators, have initiated a series of individual, bilateral proceedings against the Central Parties with the AAA. Discovery is commencing in these individual cases, which are pending before various separate arbitrators. A sample of these cases will be litigated and proceed to hearing, while the remaining cases will be stayed. Trials for the sample cases are expected to occur in the second quarter of 2017.
[5]	Individually and on behalf of all others similarly situated.

Common Stock (Details)

Common Stock (Details)	12 Months Ended
	Dec. 31, 2016
Class A Common Stock [Member]
Class of Stock [Line Items]
Common Stock, Voting Rights	Holders of Class A common stock are entitled to one vote per share
Class B Common Stock [Member]
Class of Stock [Line Items]
Common Stock, Voting Rights	holders of Class B common stock are entitled to two votes per share

Common Stock (Share Repurchase

Common Stock (Share Repurchase Programs) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Shares	7,383,000	4,176,000	0
Amount	$ 117,119,000	$ 70,000,000	$ 0
Amount remaining	62,881,000
Repurchase Program authorized September 24, 2015 [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 100,000
Shares	2,221,000	4,176,000
Amount	$ 30,000,000	$ 70,000,000
Amount remaining	0
Repurchase Program authorized February 22, 2016 [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 150,000
Shares	5,162,000	0
Amount	$ 87,119,000	$ 0
Amount remaining	$ 62,881,000

Common Stock Common Stock (Rela

Common Stock Common Stock (Related Party Transactions) (Details) - USD ($) $ / shares in Units, $ in Millions

Nov. 18, 2016

May 18, 2016

Apr. 20, 2016

Oct. 30, 2015

Dec. 31, 2016

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Aug. 02, 2016

Jul. 20, 2016

May 24, 2014

Conversion of Stock [Line Items]

trading window

3 days

Share Price

$ 24.36

$ 13.82

Common Stock, Conversion Basis

one-for-one

One-for-one

One-for-one

Cactus VPF Contract [Member]

Conversion of Stock [Line Items]

Related Party Transaction, Description of Transaction

Under the Cactus VPF contract, Cactus Holding I was required to deliver to Citigroup Global Markets Inc. ("CGMI") a variable amount of stock or cash

Related Party Transaction, Amounts of Transaction

$ 48.3

Cactus VPF Contract [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

3,300,000

Amended M Capital I VPF Contract [Member]

Conversion of Stock [Line Items]

Related Party Transaction, Description of Transaction

Under the Amended M Capital II VPF contract, M Capital II was required to deliver to Citibank N.A. a variable amount of stock or cash

Related Party Transaction, Amounts of Transaction

$ 18.5

trading window

3 days

Amended M Capital I VPF Contract [Member] | Class A Common Stock [Member]

Conversion of Stock [Line Items]

Shares collateralized

2,000,000

Amended M Capital I VPF Contract [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

13,700,000

Shares collateralized

34,300,000

Amended M Capital II VPF Contract [Member]

Conversion of Stock [Line Items]

Related Party Transaction, Description of Transaction

shares of Class A common stock. The new VPF required M Capital II to deliver a variable amount of Class A common stock, up to a maximum of approximately

Shares collateralized

12,300,000

Amended M Capital II VPF Contract [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

12,300,000

Amended Cactus I VPF Contract [Member]

Conversion of Stock [Line Items]

Related Party Transaction, Description of Transaction

On November 18, 2016, the maturity dates of the M Capital II VPFs were extended to December 5, 2017 through January 3, 2018, and the maturity dates of the Cactus Holding I VPFs were extended to December 5, 2017 through December 7, 2017.

shares of Class A common stock. The new VPF required Cactus Holding I to deliver a variable amount of Class A common stock, up to a maximum of approximately

Additional shares collateralized

0

Shares collateralized

7,000,000

Amended Cactus I VPF Contract [Member] | Class A Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

7,000,000

Previous M Capital VPF Contract [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

4,100,000

Number of Additional Securities Pledged

1,900,000

Previous M Capital VPF Contract [Member] | Class A Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

2,000,000

1,900,000

Conversion of Stock, Shares Converted

6,600,000

Shares sold by Moyes Affiliates

4,800,000

Stock Issued During Period, Shares, Conversion of Convertible Securities

1,100,000

Previous M Capital VPF Contract [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

5,100,000

12,000,000

2,200,000

6,800,000

National Hockey League Agreement [Member]

Conversion of Stock [Line Items]

Related Party Transaction, Description of Transaction

On April 20, 2016, Mr. Moyes entered into a settlement agreement with the National Hockey League ("NHL") relating to a previously disclosed lawsuit between the NHL and Mr. Moyes. As part of the settlement agreement, certain of Mr. Moyes’ adult children entered into a Non-Recourse Guaranty and Pledge Agreement with the NHL pursuant to which they guaranteed certain obligations of Mr. Moyes and certain Moyes Affiliates to the NHL. The guarantor’s obligations are collateralized by

National Hockey League Agreement [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Number Securities Pledged

2,000,000

Maximum [Member] | Amended M Capital II VPF Contract [Member]

Conversion of Stock [Line Items]

Shares collateralized

12,300,000

Maximum [Member] | Amended Cactus I VPF Contract [Member]

Conversion of Stock [Line Items]

Shares collateralized

7,000,000

Common Stock [Member]

Conversion of Stock [Line Items]

Stock Issued During Period, Shares, Conversion of Convertible Securities

0

Common Stock [Member] | Class A Common Stock [Member]

Conversion of Stock [Line Items]

Stock Issued During Period, Shares, Conversion of Convertible Securities

1,250,000

1,450,000

Common Stock [Member] | Class B Common Stock [Member]

Conversion of Stock [Line Items]

Stock Issued During Period, Shares, Conversion of Convertible Securities

(1,250,000)

(1,450,000)

Stock Plans (Stock Based Compen

Stock Plans (Stock Based Compensation Expense) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6,017		$ 6,525	$ 5,396
Income tax benefit	1,841		2,453	1,926
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,550		1,333	3,007
RSUs and restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	4,467		3,939	1,600
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 0	[1]	$ 1,253	$ 789
[1]	Targets for the performance units granted in 2014 and 2015 are not expected to be achieved.

Stock Plans (Compensation Costs

Stock Plans (Compensation Costs Not Yet Recognized) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Share Compensation Expense, Stock options	$ 682
Weighted Average Period	1 year 4 months 6 days
RSUs and restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Share Compensation Expense, Award	$ 7,979
Weighted Average Period	1 year 3 months 21 days
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Share Compensation Expense, Award	$ 478
Weighted Average Period	2 years

Stock Plans (Summary Of Activit

Stock Plans (Summary Of Activity Related To Stock Options) (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Shares Under Option
Stock options outstanding		3,224,253
Granted		195,999
Exercised		(1,253,152)	(665,531)	(1,100,998)
Expired		(11,119)
Forfeited		(37,818)
Stock options outstanding		2,118,163	3,224,253
Aggregate number of stock options expected to vest at a future date		234,300
Exercisable		1,849,432
Weighted Average Exercise Price
Stock options outstanding		$ 11.01
Granted		15.51
Exercised		10.56
Expired		13.46
Forfeited		18.87
Stock options outstanding		13.42	$ 11.01
Aggregate number of stock options expected to vest at a future date		20.93
Exercisable		$ 12.32
Weighted Average Remaining Contractual Term
Stock options outstanding		4 years 2 months 9 days	4 years 14 days
Aggregate number of stock options expected to vest at a future date		8 years 6 months 12 days
Exercisable		3 years 6 months 22 days
Aggregate Intrinsic Value
Stock options outstanding	[1]	$ 9,051
Stock options outstanding	[1]	23,175	$ 9,051
Aggregate number of stock options expected to vest at a future date	[1]	803
Exercisable	[1]	$ 22,269
Share Price		$ 24.36	$ 13.82
[1]	The aggregate intrinsic value was computed using the closing share price on December 31, 2016 of $24.36 and on December 31, 2015 of $13.82, as applicable.

Stock Plans (Weighted Average A

Stock Plans (Weighted Average Assumptions) (Detail) - $ / shares		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Dividend yield	[1]	0.00%	0.00%	0.00%
Risk-free rate of return	[2]	1.23%	1.41%	1.28%
Expected volatility	[3]	40.33%	37.22%	40.00%
Expected term (in years)	[4]	4 years 11 months 12 days	5 years 9 months 18 days	5 years 9 months 18 days
Weighted average fair value of stock options granted		$ 6.39	$ 6.96	$ 6.79
[1]	The dividend yield assumption is based on anticipated dividend payouts.
[2]	The risk-free interest rate assumption is based on the United States Treasury yield curve at the grant date with maturity dates approximately equal to the expected life at the grant date.
[3]	The Company estimates the expected volatility and expected option life assumption consistent with ASC Topic 718, Compensation – Stock Compensation. Beginning in 2016, we used our internal historical prices over the expected term of the options to determine our expected volatility. Prior to that, expected volatility was based upon an analysis of historical prices of similar market capitalized trucking group participants within the Dow Jones Total United States Market Index over the expected term of the options. The Company chose a daily measurement interval for historical volatility as it believes this better depicts the nature of employee option exercise decisions being based on shorter-term trends in the price of the underlying shares, rather than on monthly price movements.
[4]	As a result of the inability to predict the expected future employee exercise behavior, the Company estimated the expected term of the options using a simplified method based on contractual and vesting terms of the options. The Company uses historical data to estimate pre-vesting option forfeitures and records stock-based compensation expense only for those awards that are expected to vest.

Stock Plans (Summary Of Exercis

Stock Plans (Summary Of Exercise Of Stock Options) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of stock options exercised	1,253,152	665,531	1,100,998
Intrinsic value of stock options exercised	$ 14,266	$ 9,695	$ 15,830
Cash received upon exercise of stock options	13,237	6,953	11,488
Income tax benefit	$ 2,575	$ 2,147	$ 3,730

Stock Plans (Status of Nonveste

Stock Plans (Status of Nonvested Stock Options) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Shares
Granted	195,999
Weighted Average Fair Value
Granted	$ 6.39	$ 6.96	$ 6.79
Stock options
Shares
Nonvested	503,740
Granted	195,999
Vested	(393,190)
Forfeited	(37,818)
Nonvested	268,731	503,740
Weighted Average Fair Value
Nonvested at January 1, 2016	$ 6.92
Granted	6.39
Vested	6.09
Forfeited	6.82
Nonvested at December 31, 2016	$ 6.22	$ 6.92
Total fair value of shares vested	$ 2.4	$ 3.2	$ 3.2

Stock Plans (Restricted Stock A

Stock Plans (Restricted Stock Award Grant) (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	195,999
RSUs and restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	332,385
2014 Plan [Member] | RSUs and restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	332,385	228,873	221,070
Director [Member] | 2014 Plan [Member] | Restricted stock shares granted to the Board
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	32,235	16,601	17,102
Management [Member] | 2014 Plan [Member] | RSUs and restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards granted	300,150	212,272	203,968

Stock Plans Stock Plans (Rollfo

Stock Plans Stock Plans (Rollforward of Nonvested Restricted Stock Awards) (Details) - $ / shares		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Shares
Granted		195,999
Weighted Average Fair Value
Granted		$ 6.39		$ 6.96	$ 6.79
RSUs and restricted stock
Shares
Nonvested		418,281
Granted		332,385
Vested	[1]	(210,102)
Forfeited		(27,242)
Nonvested		513,322	[2]	418,281
Weighted Average Fair Value
Nonvested at January 1, 2016		$ 22.54
Granted		15.54
Vested	[1]	21.36
Forfeited		21.14
Nonvested at December 31, 2016		$ 18.55	[2]	$ 22.54
Director [Member] | Restricted Stock [Member]
Shares
Vested	[1]	(19,221)
Nonvested	[2]	32,235
[1]	Includes 19,221 shares of restricted stock previously issued to Board members, and vested during 2016.
[2]	Includes 32,235 shares of restricted stock previously issued to Board members, but not yet vested as of December 31, 2016.

Stock Plans (Rollforward of Non

Stock Plans (Rollforward of Nonvested Performance Shares) (Details) - $ / shares		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Shares
Granted		195,999
Weighted Average Fair Value
Granted		$ 6.39	$ 6.96	$ 6.79
Performance units
Shares
Nonvested		215,333
Granted		91,492
Vested	[1]	(96,650)
Forfeited		(5,005)
Nonvested		205,170	215,333
Weighted Average Fair Value
Nonvested at January 1, 2016		$ 18.99
Granted		15.51
Vested	[1]	13.36
Forfeited		24
Nonvested at December 31, 2016		$ 19.97	$ 18.99
Requisite service period for performance shares		3 years
[1]	The performance period for the performance units granted in May 2014 ended on December 31, 2016. The Board is not expected to approve the final vesting of these awards subsequent to December 31, 2016, based on the results of the three-year performance period, but final decision is still pending as of the filing date of this Annual Report on Form 10-K.

Stock Plans (Narrative) (Detail

Stock Plans (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, vesting period	3 years
Maximum purchasing power of common stock for an employee during offering period	$ 6,250
Maximum purchasing power of common stock for an employee during a calendar year	$ 25,000
Maximum percent of total voting power or value of all classes of common stock which restricts from participation of ESPP	5.00%
2012 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	2,000,000
Employment period for eligibility of employees participation	90 days
Percentage of payroll deductions from employees compensation	15.00%
Percentage of fair market value of the purchase price	95.00%
Number of shares purchased by the employees	77,462
Weighted-average fair value of the shares purchased	$ 17.29
Number of additional shares authorized for issuance	1,700,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term for the options granted	10 years	10 years
Vesting rights rate	33.00%	33.30%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, vesting period	3 years
Non-transferable period for selling shares	4 years
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period for performance shares	3 years
Class A Common Stock [Member] | 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance			12,000,000
Number of shares remaining available	4,300,000

Weighted Average Shares Outs103

Weighted Average Shares Outstanding (Calculation Of Basic And Diluted Earnings Per Share Attributable To Stockholders) (Detail) - shares shares in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Basic weighted average common shares outstanding		134,139	142,018	141,431
Dilutive effect of stock options		1,355	1,650	2,044
Diluted weighted average common shares outstanding		135,494	143,668	143,475
Anti-dilutive shares excluded from diluted earnings per share	[1]	156	354	162
[1]	Shares were excluded from the dilutive-effect calculation because the outstanding options' exercise prices were greater than the average market price of the Company's common shares during the period.

Fair Value Measurement (Carryin

Fair Value Measurement (Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Detail) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Financial Assets:
Restricted investments, Carrying Value	[1]	$ 22,717	$ 23,215
Restricted investments, Estimated Fair Value	[1]	22,688	23,190
Financial Liabilities:
2015 Agreement: New Term Loan A, Carrying Value		501,805	679,177
Accounts receivable securitization, Carrying Value		279,285	223,927
Revolving line of credit, Carrying Value	[2]	130,000	200,000
Debt Issuance Costs, Net		3,222	4,264
2015 Agreement, Term Loan A [Member]
Financial Liabilities:
2015 Agreement: New Term Loan A, Carrying Value	[3],[4]	492,912	668,055
2015 Agreement: New Term Loan A, Estimated Fair Value	[4]	494,250	669,750
Debt Issuance Costs, Net		1,338	1,695
2015 RSA [Member]
Financial Liabilities:
Accounts receivable securitization, Carrying Value	[5]	279,285	223,927
Accounts receivable securitization, Estimated Fair Value	[5]	280,000	225,000
Debt Issuance Costs, Net		700	1,100
2015 Agreement, Credit Facility [Member]
Financial Liabilities:
Revolving line of credit, Carrying Value		130,000	200,000
Revolving line of credit, Estimated Fair Value		$ 130,000	$ 200,000
[1]	Restricted investments are included in "Restricted investments, held to maturity, amortized cost."
[2]	The Company also had outstanding letters of credit under the New Revolver, primarily related to workers' compensation and self-insurance liabilities of $97.0 million at December 31, 2016 and $95.0 million at December 31, 2015.
[3]	Refer to Note 21 for information regarding the fair value of debt.
[4]	The New Term Loan A is included in "Current portion of long-term debt" and "Long-term debt, less current portion." Carrying value is net of $1.3 million and $1.7 million DLCs as of December 31, 2016 and 2015, respectively.
[5]	Carrying value is net of $0.7 million and $1.1 million DLCs as of December 31, 2016 and 2015, respectively.

Fair Value Measurement - Recurr

Fair Value Measurement - Recurring Basis (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Assets, Fair Value Disclosure, Recurring	$ 0	$ 0
Liabilities, Fair Value Disclosure, Recurring	$ 0	$ 0

Fair Value Measurement - Nonrec

Fair Value Measurement - Nonrecurring basis (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 19, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, Fair Value Disclosure, Nonrecurring		$ 0	$ 0
Notes receivable						$ (2,300,000)
Non-cash impairments of non-operating assets		0	(1,480,000)	$ 0
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	[1]		0
Non-cash impairments of non-operating assets	[1]		(1,480,000)
Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 1 Inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	[1]		0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	[1]		0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	[1]		$ 0
Software | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[2]	0
Non-cash impairments of non-operating assets	[2]	(520,000)
Software | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 1 Inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[2]	0
Software | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[2]	0
Software | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[2]	0
Equipment | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[3]	1,963,000			$ 2,200,000
Non-cash impairments of non-operating assets	[3]	(250,000)
Equipment | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 1 Inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[3]	0
Equipment | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[3]	0
Equipment | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements at Reporting Date Using Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[3]	$ 1,963,000
[1]	In September 2013, the Company agreed to advance up to $2.3 million, pursuant to an unsecured promissory note, to an independent fleet contractor that transported freight on Swift's behalf. In March 2015, management became aware that the independent contractor violated various covenants outlined in the unsecured promissory note, which created an event of default that made the principal and accrued interest immediately due and payable. As a result of this event of default, as well as an overall decline in the independent contractor's financial condition, management re-evaluated the fair value of the unsecured promissory note. At March 31, 2015, management determined that the remaining balance due from the independent contractor to the Company was not collectible, which resulted in a $1.5 million pre-tax adjustment that was recorded in "Non-cash impairments of non-operating assets" in the Company's consolidated income statements.
[2]	During the three months ended December 31, 2016, certain operations software related to the Company's logistics business was determined to be fully impaired based on a significant decrease in the expected useful life of the software. This resulted in a pre-tax impairment loss of $0.5 million, which was recorded in "Impairments" within operating income in the consolidated income statement.
[3]	During the three months ended December 31, 2016, management reassessed the fair value of certain IEL tractors, which had a total book value of $2.2 million, determining that there was a pre-tax impairment loss of $0.3 million. The impairment loss was recorded in "Impairments" within operating income in the consolidated income statement.

Related Party Transactions (Sch

Related Party Transactions (Schedule Of Services Received And Provided By Company) (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Receivable		$ 193,000	$ 91,000
Payable		23,000	78,000
Thermo King
Related Party Transaction [Line Items]
Receivable		0	4,000
Payable		22,000	46,000
Central Freight Lines, Inc. [Member]
Related Party Transaction [Line Items]
Receivable		118,000	3,000
Payable		1,000	3,000
SME Industries [Member]
Related Party Transaction [Line Items]
Receivable		72,000	79,000
Payable		0	0
Other Affiliated Entities [Member]
Related Party Transaction [Line Items]
Receivable		3,000	5,000
Payable		0	29,000
Common Market Trading LLC [Member]
Related Party Transaction [Line Items]
Received by Swift		0	63,000
Freight Services [Member]
Related Party Transaction [Line Items]
Provided by Swift		914,000	1,219,000	$ 224,000
Received by Swift		26,000	25,000	24,000
Freight Services [Member] | Thermo King
Related Party Transaction [Line Items]
Provided by Swift	[1]	1,000	4,000	0
Received by Swift	[1]	0	0	0
Freight Services [Member] | Central Freight Lines, Inc. [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	83,000	237,000	25,000
Received by Swift	[2]	26,000	25,000	24,000
Freight Services [Member] | SME Industries [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	830,000	978,000	185,000
Received by Swift	[2]	0	0	0
Freight Services [Member] | Other Affiliated Entities [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	0	0	14,000
Received by Swift	[2]	0	0	0
Facility and Equipment Leases [Member]
Related Party Transaction [Line Items]
Provided by Swift		1,173,000	1,122,000	863,000
Received by Swift		372,000	436,000	628,000
Facility and Equipment Leases [Member] | Thermo King
Related Party Transaction [Line Items]
Provided by Swift	[1]	0	12,000	0
Received by Swift	[1]	0	0	0
Facility and Equipment Leases [Member] | Central Freight Lines, Inc. [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	1,154,000	1,090,000	843,000
Received by Swift	[2]	372,000	435,000	400,000
Facility and Equipment Leases [Member] | Other Affiliated Entities [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	19,000	20,000	20,000
Received by Swift	[2]	0	1,000	228,000
Other Services [Member]
Related Party Transaction [Line Items]
Provided by Swift		104,000	144,000	392,000
Received by Swift		1,151,000	1,293,000	956,000
Other Services [Member] | Thermo King
Related Party Transaction [Line Items]
Provided by Swift	[1]	0	1,000	0
Received by Swift	[1]	633,000	518,000	184,000
Other Services [Member] | Central Freight Lines, Inc. [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	24,000	142,000	388,000
Received by Swift	[2]	0	0	0
Other Services [Member] | Swift Aircraft Management [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	0	0	0
Received by Swift	[2]	501,000	636,000	699,000
Other Services [Member] | SME Industries [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	69,000	0	0
Received by Swift	[2]	0	0	0
Other Services [Member] | Other Affiliated Entities [Member]
Related Party Transaction [Line Items]
Provided by Swift	[2]	11,000	1,000	4,000
Received by Swift	[2]	$ 17,000	$ 139,000	$ 73,000
[1]	Thermo King West, Inc. and Thermo King Chesapeake, Inc. are owned by William Riley III, a member of Swift's Board. Transactions associated with the Thermo King affiliated entities primarily consist of parts and equipment purchases by Swift. Swift also provided freight services, equipment leasing, and other services to the Thermo King affiliated entities.
[2]	Entities affiliated with majority shareholder, Board member, and (prior to December 31, 2016) Chief Executive Officer, Jerry Moyes include Central Freight Lines, SME Industries, Swift Aircraft Management, Compensi Services, Common Market Trading, LLC, and Southwest Premier Properties. Transactions with these entities that are controlled by and/or are otherwise affiliated with Jerry Moyes, include freight services, facility leases, equipment leases, and other services. •Freight Services Provided by Swift — The rates the Company charges for freight services to each of these companies for transportation services are market rates, which are comparable to rates charged to third-party customers. These transportation services provided to affiliates provide the Company with an additional source of operating revenue at its normal freight rates.•Freight Services Received by Swift — Transportation services received from Central Freight represent LTL freight services rendered to haul parts and equipment to Company shop locations.•Other Services Provided by Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services.•Other Services Received by Swift — Executive air transport, fuel storage, event fees, equipment purchases, miscellaneous repair services, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company.In 2015, the Company purchased bulk diesel fuel totaling $63 thousand, from Common Market Trading LLC, which is also included in other services received by Swift from other affiliates. Common Market Trading LLC was initially owned by both Jerry Moyes and his brother, Ronald Moyes, but wholly owned by Ronald Moyes as of October 20, 2015. The Company purchased no bulk diesel fuel from Common Market Trading LLC in 2016.

Jerry Moyes' Retirement (Detail

Jerry Moyes' Retirement (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
		Sep. 30, 2016	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities, Initiation Date		Sep. 8, 2016
Restructuring and Related Activities, Completion Date		Dec. 31, 2019
Monthly consulting fee		$ 200
Restructuring Charges		7,100
Other Restructuring Costs		$ 300
Restructuring and Related Cost, Caption that Includes Restructuring Charges		Salaries, wages, and employee benefits
Rollforward of accrued liability for the consulting fees [Abstract]
Balance at December 31, 2015			$ 0
Additions to accrual		$ 6,800	6,837
Less: payments			(162)
Balance at December 31, 2016	[1]		$ 6,675
[1]	The balance is included in "Other liabilities" (noncurrent) and "Accrued liabilities" (current) in the consolidated balance sheet, based on the timing of the expected payment. The $0.3 million impact of the equity award modification is excluded from the accrual balance because it is classified as "Additional paid-in capital" in the consolidated balance sheet.

Information by Segment (Summary

Information by Segment (Summary Of Financial Information By Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Operating revenue	$ 1,038,614	$ 1,013,226	$ 1,011,854	$ 967,823	$ 1,089,801	$ 1,064,973	$ 1,059,404	$ 1,015,144	$ 4,031,517	$ 4,229,322	$ 4,298,724
Operating income (loss)	$ 75,471	$ 39,853	$ 74,205	$ 52,483	$ 121,707	$ 74,921	$ 98,476	$ 75,000	242,012	370,104	370,070
Depreciation and amortization of property and equipment									267,134	251,735	221,122
Truckload [Member]
Segment Reporting Information [Line Items]
Operating revenue									2,048,049	2,204,114	2,301,010
Operating income (loss)									181,781	257,007	258,072
Depreciation and amortization of property and equipment									125,611	121,144	113,875
Dedicated [Member]
Segment Reporting Information [Line Items]
Operating revenue									971,246	927,657	892,078
Operating income (loss)									108,481	82,735	75,794
Depreciation and amortization of property and equipment									68,090	62,221	53,682
Swift Refrigerated [Member]
Segment Reporting Information [Line Items]
Operating revenue									341,280	380,251	417,980
Operating income (loss)									(12,844)	17,080	14,035
Depreciation and amortization of property and equipment									16,737	16,160	12,510
Intermodal [Member]
Segment Reporting Information [Line Items]
Operating revenue									360,157	390,572	401,577
Operating income (loss)									(547)	4,128	8,298
Depreciation and amortization of property and equipment									11,839	13,723	10,875
Subtotal [Member]
Segment Reporting Information [Line Items]
Operating revenue									3,720,732	3,902,594	4,012,645
Operating income (loss)									276,871	360,950	356,199
Depreciation and amortization of property and equipment									222,277	213,248	190,942
Non-reportable segment [Member]
Segment Reporting Information [Line Items]
Operating revenue									386,349	407,781	342,969
Operating income (loss)									(34,859)	9,154	13,871
Depreciation and amortization of property and equipment									44,857	38,487	30,180
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenue									$ (75,564)	$ (81,053)	$ (56,890)

Information by Geography (Narra

Information by Geography (Narrative) (Detail) - Segment	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting [Abstract]
Number of Reportable Segments	4
Percentage of foreign operations total revenue	5.00%	5.00%	5.00%
Long lived assets of foreign operations	5.00%	5.00%

Information by Segment, Geog111

Information by Segment, Geography, and Customer Concentration Information by Customer Concentration (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	10.00%
Sales Revenue, Net [Member] | Major Customer And Its Subsidiaries [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	14.00%	12.00%	11.00%

Quarterly Result of Operatio112

Quarterly Result of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Selected Quarterly Financial Information [Abstract]
Operating Revenue	$ 1,038,614	$ 1,013,226	$ 1,011,854	$ 967,823	$ 1,089,801	$ 1,064,973	$ 1,059,404	$ 1,015,144	$ 4,031,517	$ 4,229,322	$ 4,298,724
Operating income	75,471	39,853	74,205	52,483	121,707	74,921	98,476	75,000	242,012	370,104	370,070
Net income	$ 50,442	$ 24,024	$ 42,896	$ 31,905	$ 72,502	$ 36,281	$ 50,954	$ 37,840	$ 149,267	$ 197,577	$ 161,152
Basic earnings per share	$ 0.38	$ 0.18	$ 0.32	$ 0.23	$ 0.52	$ 0.25	$ 0.36	$ 0.27	$ 1.11	$ 1.39	$ 1.14
Diluted earnings per share	$ 0.38	$ 0.18	$ 0.32	$ 0.23	$ 0.51	$ 0.25	$ 0.35	$ 0.26	$ 1.10	$ 1.38	$ 1.12