Knight-Swift Transportation (KNX) 10-Q 4 Aug 21 2021 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Jul. 28, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	001-35007
Entity Registrant Name	Knight-Swift Transportation Holdings Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-5589597
Entity Address, Address Line One	2002 West Wahalla Lane
Entity Address, City or Town	Phoenix
Entity Address, State or Province	AZ
Entity Address, Postal Zip Code	85027
City Area Code	602
Local Phone Number	269-2000
Title of 12(b) Security	Common Stock $0.01 Par Value
Trading Symbol	KNX
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		165,975,952
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001492691
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) shares in Thousands, $ in Thousands		Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents		$ 179,032	$ 156,699
Cash and cash equivalents – restricted	[1]	51,637	39,328
Restricted investments, held-to-maturity, amortized cost	[2]	8,589	9,001
Trade receivables, net of allowance for doubtful accounts of $22,157 and $22,093, respectively		648,435	578,479
Contract balance – revenue in transit		20,913	14,560
Prepaid expenses		58,722	71,649
Assets held for sale		17,599	29,756
Income tax receivable		29,369	2,903
Other current assets		60,581	20,988
Total current assets		1,074,877	923,363
Gross property and equipment		4,401,293	4,223,348
Less: accumulated depreciation and amortization		(1,389,477)	(1,230,696)
Property and equipment, net		3,011,816	2,992,652
Operating lease right-of-use-assets		91,258	113,296
Goodwill		2,971,023	2,922,964
Intangible assets, net		1,403,483	1,389,245
Other long-term assets		130,002	126,482
Total assets		8,682,459	8,468,002
Current liabilities:
Accounts payable		151,704	101,001
Accrued payroll and purchased transportation		191,906	160,888
Accrued liabilities		87,637	88,894
Claims accruals – current portion		169,093	174,928
Finance lease liabilities and long-term debt – current portion		72,423	52,583
Operating lease liabilities – current portion		32,785	47,496
Accounts receivable securitization – current portion		0	213,918
Total current liabilities		705,548	839,708
Revolving line of credit		55,000	210,000
Long-term debt – less current portion		299,219	298,907
Finance lease liabilities – less current portion		165,644	138,243
Operating lease liabilities – less current portion		60,958	69,852
Accounts receivable securitization – less current portion		278,372	0
Claims accruals – less current portion		168,152	174,814
Deferred tax liabilities		806,398	815,941
Other long-term liabilities		45,115	48,497
Total liabilities		2,584,406	2,595,962
Commitments and contingencies (Notes 3, 9, and 10)
Stockholders’ equity:
Preferred stock, par value $0.01 per share; 10,000 shares authorized; none issued		$ 0	$ 0
Parenthetical - Preferred stock, par value (in dollars per share)		$ 0.01	$ 0.01
Parenthetical - Preferred stock, shares authorized (in shares)		10,000	10,000
Parenthetical - Preferred stock, shares issued (in shares)		0	0
Common stock, par value $0.01 per share; 500,000 shares authorized; 165,711 and 166,553 shares issued and outstanding as of June 30, 2021 and December 31, 2020, respectively.		$ 1,657	$ 1,665
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized (in shares)		500,000	500,000
Common stock, shares issued (in shares)		165,711	166,553
Common stock, shares outstanding (in shares)		165,711	166,553
Additional paid-in capital		$ 4,325,915	$ 4,301,424
Retained earnings		1,757,689	1,566,759
Total Knight-Swift stockholders' equity		6,085,261	5,869,848
Noncontrolling interest		12,792	2,192
Total stockholders’ equity		6,098,053	5,872,040
Total liabilities and stockholders’ equity		$ 8,682,459	$ 8,468,002
Common Class A [Member]
Stockholders’ equity:
Common stock, shares outstanding (in shares)		165,711	166,553
Total stockholders’ equity		$ 1,657	$ 1,665
[1]	Reflects cash and cash equivalents that are primarily restricted for claims payments.
[2]	Refer to Note 4 for the differences between the carrying amounts and estimated fair values of the Company's restricted investments, held-to-maturity.

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Total revenue	$ 1,315,701	$ 1,060,698	$ 2,538,715	$ 2,185,496
Operating expenses:
Salaries, wages, and benefits	377,613	365,311	747,983	720,144
Fuel	126,055	86,381	244,291	208,236
Operations and maintenance	71,313	66,067	139,383	134,471
Insurance and claims	58,776	45,302	114,419	99,582
Operating taxes and licenses	21,717	20,883	43,765	43,052
Communications	4,635	4,902	9,672	9,776
Depreciation and amortization of property and equipment	123,606	114,601	243,521	224,822
Amortization of intangibles	11,984	11,474	23,733	22,948
Rental expense	13,399	22,372	30,263	47,747
Purchased transportation	304,157	200,107	562,387	425,383
Impairments	0	353	0	1,255
Miscellaneous operating expenses	11,331	20,778	25,924	43,794
Total operating expenses	1,124,586	958,531	2,185,341	1,981,210
Operating income	191,115	102,167	353,374	204,286
Other income (expenses):
Interest income	270	437	564	1,269
Interest expense	(3,307)	(4,021)	(6,793)	(10,128)
Other income, net	16,840	8,499	32,945	1,992
Total other income (expenses), net	13,803	4,915	26,716	(6,867)
Income before income taxes	204,918	107,082	380,090	197,419
Income tax expense	51,783	26,815	97,112	51,369
Net income	153,135	80,267	282,978	146,050
Net income attributable to noncontrolling interest	(331)	(78)	(384)	(435)
Net income attributable to Knight-Swift	$ 152,804	$ 80,189	$ 282,594	$ 145,615
Earnings per share:
Basic (in dollars per share)	$ 0.92	$ 0.47	$ 1.70	$ 0.86
Diluted (in dollars per share)	0.92	0.47	1.69	0.85
Dividends declared per share: (in dollars per share)	$ 0.10	$ 0.08	$ 0.18	$ 0.16
Weighted average shares outstanding:
Basic (in shares)	165,577	169,948	165,751	170,283
Diluted (in shares)	166,585	170,624	166,750	170,958
Revenue, excluding trucking fuel surcharge [Member]
Total revenue	$ 1,212,872	$ 997,597	$ 2,345,977	$ 2,024,692
Trucking fuel surcharge revenue [Member]
Total revenue	$ 102,829	$ 63,101	$ 192,738	$ 160,804

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Statement of Cash Flows [Abstract]
Net income	$ 282,978	$ 146,050
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment, and intangibles	267,254	247,770
Gain on sale of property and equipment	(25,592)	(4,724)
Impairments	0	1,255
Deferred income taxes	(9,541)	23,112
Non-cash lease expense	26,743	46,493
Non-cash adjustment to fair value of convertible note	12,631	0
Other adjustments to reconcile net income to net cash provided by operating activities	9,347	19,229
Increase (decrease) in cash resulting from changes in:
Trade receivables	(70,067)	(11,440)
Income tax receivable	(26,466)	11,124
Accounts payable	28,935	8,417
Accrued liabilities and claims accrual	6,512	(75,069)
Operating lease liabilities	(28,311)	(48,243)
Other assets and liabilities	10,343	19,386
Net cash provided by operating activities	459,504	383,360
Cash flows from investing activities:
Proceeds from maturities of held-to-maturity investments	2,850	6,950
Purchases of held-to-maturity investments	(2,555)	(7,852)
Proceeds from sale of property and equipment, including assets held for sale	127,068	64,463
Purchases of property and equipment	(247,549)	(259,641)
Expenditures on assets held for sale	(765)	(418)
Net cash, restricted cash, and equivalents invested in acquisitions	(63,305)	(46,811)
Investment in convertible note	25,000	0
Other cash flows from investing activities	12,340	(9,757)
Net cash used in investing activities	(196,916)	(253,066)
Cash flows from financing activities:
Repayment of finance leases and long-term debt	(50,428)	(31,893)
Repayments on revolving lines of credit, net	(155,000)	(44,000)
Borrowings under accounts receivable securitization	80,000	0
Repayment of accounts receivable securitization	(15,000)	(40,000)
Proceeds from common stock issued	5,302	9,892
Repurchases of the Company's common stock	(53,661)	(34,630)
Dividends paid	(30,332)	(27,673)
Other cash flows from financing activities	(8,679)	(5,467)
Net cash used in financing activities	(227,798)	(173,771)
Net increase (decrease) in cash, restricted cash, and equivalents	34,790	(43,477)
Cash, restricted cash, and equivalents at beginning of period	197,277	202,228
Cash, restricted cash, and equivalents at end of period	232,067	158,751
Cash paid during the period for:
Interest	5,719	10,455
Income taxes	133,284	3,632
Other Significant Noncash Transactions [Line Items]
Equipment acquired included in accounts payable	8,063	27,463
Contingent consideration associated with acquisition	5,000	18,245
Right-of-use assets obtained in exchange for operating lease liabilities	4,146	1,633
Property and equipment obtained in exchange for finance lease liabilities reclassified from operating lease liabilities	55,370	0
Financing provided to independent contractors for equipment sold [Member]
Other Significant Noncash Transactions [Line Items]
Other non-cash investing and financing activities	776	2,553
Transfers from property and equipment to assets held for sale [Member]
Other Significant Noncash Transactions [Line Items]
Other non-cash investing and financing activities	51,310	37,779
Noncontrolling Interest Associated With Acquisition
Other Significant Noncash Transactions [Line Items]
Other non-cash investing and financing activities	10,281	0
Property and equipment obtained in exchange for finance lease liabilities from operating lease liabilities
Other Significant Noncash Transactions [Line Items]
Property and equipment obtained in exchange for finance lease liabilities reclassified from operating lease liabilities	42,298	48,659
Warehousing Co [Member]
Other Significant Noncash Transactions [Line Items]
Right-of-use assets obtained in exchange for operating lease liabilities		$ 12,356
Eleos [Member]
Other Significant Noncash Transactions [Line Items]
Right-of-use assets obtained in exchange for operating lease liabilities	$ 560

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) Reconciliation of Cash, Restricted Cash, and Cash Equivalents - USD ($) $ in Thousands		Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Statement of Cash Flows [Abstract]
Cash and cash equivalents		$ 179,032	$ 156,699	$ 117,760	$ 159,722
Cash and cash equivalents – restricted	[1]	51,637	39,328	39,583	41,331
Other long-term assets	[1]	1,398	1,250	1,408	1,175
Cash, restricted cash, and equivalents		$ 232,067	$ 197,277	$ 158,751	$ 202,228
[1]	Reflects cash and cash equivalents that are primarily restricted for claims payments.

Condensed Consolidated Statem_4

Condensed Consolidated Statement Of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total Knight-Swift Equity [Member]	Noncontrolling Interest [Member]	Common Class A [Member]
Beginning balance, shares at Dec. 31, 2019						170,688
Beginning balance, value at Dec. 31, 2019	$ 5,668,303	$ 4,269,043	$ 1,395,465	$ 5,666,215	$ 2,088	$ 1,707
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued to employees (Shares)						567
Common stock issued to employees	8,314	8,309		8,314		$ 5
Common stock issued to the Board (Shares)						13
Common stock issued to the Board	515	515		515		$ 0
Common stock issued under ESPP (Shares)						33
Common stock issued under ESPP	1,063	1,063		1,063		$ 0
Company shares repurchased (Shares)						(1,139)
Company shares repurchased	(34,630)		(34,619)	(34,630)		$ (11)
Shares withheld – RSU settlement	(4,500)		(4,500)	(4,500)
Employee stock-based compensation expense	$ 8,363	8,363		8,363
Dividends declared per share: (in dollars per share)	$ 0.16
Cash dividends paid and dividends accrued	$ (27,495)		(27,495)	(27,495)
Net income attributable to Knight-Swift	145,615		145,615	145,615
Distribution to noncontrolling interest	(394)				(394)
Net income attributable to noncontrolling interest	435				435
Ending balance, shares at Jun. 30, 2020						170,162
Ending balance, value at Jun. 30, 2020	5,765,589	4,287,293	1,474,466	5,763,460	2,129	$ 1,701
Beginning balance, shares at Mar. 31, 2020						169,776
Beginning balance, value at Mar. 31, 2020	5,690,324	4,275,834	1,410,527	5,688,059	2,265	$ 1,698
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued to employees (Shares)						356
Common stock issued to employees	5,603	5,600		5,603		$ 3
Common stock issued to the Board (Shares)						13
Common stock issued to the Board	515	515		515		$ 0
Common stock issued under ESPP (Shares)						17
Common stock issued under ESPP	517	517		517		$ 0
Shares withheld – RSU settlement	(2,529)		(2,529)	(2,529)
Employee stock-based compensation expense	$ 4,827	4,827		4,827
Dividends declared per share: (in dollars per share)	$ 0.08
Cash dividends paid and dividends accrued	$ (13,721)		(13,721)	(13,721)
Net income attributable to Knight-Swift	80,189		80,189	80,189
Distribution to noncontrolling interest	(214)				(214)
Net income attributable to noncontrolling interest	78				78
Ending balance, shares at Jun. 30, 2020						170,162
Ending balance, value at Jun. 30, 2020	$ 5,765,589	4,287,293	1,474,466	5,763,460	2,129	$ 1,701
Beginning balance, shares at Dec. 31, 2020	166,553					166,553
Beginning balance, value at Dec. 31, 2020	$ 5,872,040	4,301,424	1,566,759	5,869,848	2,192	$ 1,665
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued to employees (Shares)						418
Common stock issued to employees	3,396	3,391		3,396		$ 5
Common stock issued to the Board (Shares)						12
Common stock issued to the Board	575	575		575		$ 0
Common stock issued under ESPP (Shares)						31
Common stock issued under ESPP	1,331	1,331		1,331		$ 0
Company shares repurchased (Shares)						(1,303)
Company shares repurchased	(53,661)		(53,648)	(53,661)		$ (13)
Shares withheld – RSU settlement	(7,947)		(7,947)	(7,947)
Employee stock-based compensation expense	$ 19,194	19,194		19,194
Dividends declared per share: (in dollars per share)	$ 0.18
Cash dividends paid and dividends accrued	$ (30,069)		(30,069)	(30,069)
Net income attributable to Knight-Swift	282,594		282,594	282,594
Investment in noncontrolling interest	10,281				10,281
Distribution to noncontrolling interest	(65)				(65)
Net income attributable to noncontrolling interest	$ 384				384
Ending balance, shares at Jun. 30, 2021	165,711					165,711
Ending balance, value at Jun. 30, 2021	$ 6,098,053	4,325,915	1,757,689	6,085,261	12,792	$ 1,657
Beginning balance, shares at Mar. 31, 2021						165,488
Beginning balance, value at Mar. 31, 2021	5,949,338	4,309,792	1,625,397	5,936,844	12,494	$ 1,655
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued to employees (Shares)						198
Common stock issued to employees	1,387	1,385		1,387		$ 2
Common stock issued to the Board (Shares)						12
Common stock issued to the Board	575	575		575		$ 0
Common stock issued under ESPP (Shares)						13
Common stock issued under ESPP	631	631		631		$ 0
Shares withheld – RSU settlement	(3,788)		(3,788)	(3,788)
Employee stock-based compensation expense	$ 13,532	13,532		13,532
Dividends declared per share: (in dollars per share)	$ 0.10
Cash dividends paid and dividends accrued	$ (16,724)		(16,724)	(16,724)
Net income attributable to Knight-Swift	152,804		152,804	152,804
Distribution to noncontrolling interest	(33)				(33)
Net income attributable to noncontrolling interest	$ 331				331
Ending balance, shares at Jun. 30, 2021	165,711					165,711
Ending balance, value at Jun. 30, 2021	$ 6,098,053	$ 4,325,915	$ 1,757,689	$ 6,085,261	$ 12,792	$ 1,657

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited)(Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Receivables [Abstract]
Parenthetical - allowance for doubtful accounts	$ 22,157	$ 22,093

Introduction and Basis of Prese

Introduction and Basis of Presentation	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Introduction and Basis of Presentation	Introduction and Basis of Presentation Certain acronyms and terms used throughout this Quarterly Report are specific to the Company, commonly used in the trucking industry, or are otherwise frequently used throughout this document. Definitions for these acronyms and terms are provided in the "Glossary of Terms," available in the front of this document. Description of Business Knight-Swift is a transportation solutions provider, headquartered in Phoenix, Arizona. During the first half of 2021, the Company operated an average of 18,129 tractors (comprised of 16,225 company tractors and 1,904 independent contractor tractors) and 60,382 trailers within the Trucking segment. Additionally, the Company operated an average of 605 tractors and 10,844 containers in the Intermodal segment. As of June 30, 2021 , the Company's three reportable segments are Trucking, Logistics, and Intermodal. Basis of Presentation The condensed consolidated financial statements and footnotes included in this Quarterly Report include the accounts of Knight-Swift Transportation Holdings Inc. and its subsidiaries and should be read in conjunction with the consolidated financial statements and footnotes included in Knight-Swift's 2020 Annual Report. In management's opinion, these condensed consolidated financial statements were prepared in accordance with GAAP and include all adjustments necessary (consisting of normal recurring adjustments) for the fair statement of the periods presented. With respect to transactional/durational data, references to years pertain to calendar years. Similarly, references to quarters pertain to calendar quarters. Seasonality In the transportation industry, results of operations generally follow a seasonal pattern. Freight volumes in the first quarter are typically lower due to less consumer demand, customers reducing shipments following the holiday season, and inclement weather. At the same time, operating expenses generally increase, and tractor productivity of the Company's fleet, independent contractors, and third-party carriers decreases during the winter months due to decreased fuel efficiency, increased cold weather-related equipment maintenance and repairs, and increased insurance claims and costs attributed to higher accident frequency from harsh weather. These factors typically lead to lower operating profitability, as compared to other parts of the year. Additionally, beginning in the latter half of the third quarter and continuing into the fourth quarter, the Company typically experiences surges pertaining to holiday shopping trends toward delivery of gifts purchased over the Internet, as well as the length of the holiday season (consumer shopping days between Thanksgiving and Christmas). However, cyclical changes in the trucking industry, including imbalances in supply and demand, can override the seasonality faced in the industry. Impact of COVID-19 The Company continues to operate its business through the COVID-19 pandemic, including recent variants, and has taken additional precautions to ensure the safety of its employees, customers, vendors, and the communities in which it operates. There are various uncertainties that have arisen from the COVID-19 pandemic. While management is continuing to monitor the impact of the pandemic on Knight-Swift, including its employees, customers, independent contractors, stockholders, and other business partners and stakeholders, it is difficult to predict the impact that the pandemic will have on future results of its operations, financial position, and liquidity. This has caused some uncertainties around various accounting estimates. Due to these uncertainties, the Company's accounting estimates may change, as management's assessment of the impacts of the COVID-19 pandemic continues to evolve.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	6 Months Ended
	Jun. 30, 2021
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting PronouncementsThere have been no ASUs issued since the filing date of the 2020 annual report that may have a material impact on the Company.

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2021
Business Combinations [Abstract]
Acquisition	Acquisitions AAA Cooper Transportation Acquisition On July 5, 2021, the Company acquired 100% of Dothan, Alabama-based AAA Cooper Transportation and an affiliated entity ("ACT"). ACT is a leading less-than-truckload ("LTL") carrier that also offers dedicated contract carriage and ancillary services. The total purchase price consideration of $1.31 billion included $1.30 billion in cash and $10.0 million in Knight-Swift shares issued to the sellers at closing. Additionally, the Company assumed $36.7 million in debt, net of cash. Cash was funded from the 2021 Term Loan, as well as existing Knight-Swift liquidity. ACT was an S corporation for tax purposes, and the transaction included an election under Internal Revenue Code Section 338(h)(10). The Stock Purchase Agreement contains customary representations, warranties, and covenants. The results of ACT will be included in our consolidated results beginning in the third quarter of 2021. The Company has not completed the initial accounting for this transaction as it is still in the preliminary stages of assessing the fair value of the underlying tangible and intangible assets. On July 6, 2021, Knight-Swift entered into the $1.2 billion 2021 Term Loan with Bank of America, N.A. The 2021 Term Loan is incremental to, and is separate from, the 2017 Debt Agreement. The 2021 Term Loan was fully funded on July 6, 2021 and there are no scheduled principal payments prior to maturity in October 2022. The interest rate applicable to the 2021 Term Loan is subject to a leverage-based grid and equals the BSBY rate (Bloomberg Short-term Bank Yield index) plus 1.000% at closing. The 2021 Term Loan contains similar terms to the 2017 Debt Agreement, including the financial covenants, usual and customary events of default for a facility of this nature, and certain usual and customary restrictions and covenants. UTXL Enterprises, Inc. On June 1, 2021, pursuant to a stock purchase agreement (the "SPA") the Company, through a wholly owned subsidiary, acquired 100.0% of the equity interests of UTXL Enterprises, Inc. (“UTXL”), a premier third-party logistics company which specializes in over-the-road full truckload and multi-stop loads. The total purchase price consideration of $37.2 million, including cash on hand and net working capital adjustments, consisted of $32.2 million in cash to the sellers at closing, which was funded through cash-on-hand and borrowing on the Revolver on the transaction date. At closing $2.25 million of the cash consideration was placed in escrow to secure certain of the sellers' indemnification obligations and remains subject to further adjustments. The purchase price also included contingent consideration consisting of two additional annual payments of up to $2.5 million each (or $5.0 million in total), representing the maximum possible annual deferred payments to the sellers based on UTXL’s operating ratio and revenue growth targets for each of the twelve-month periods ending May 31, 2022 and May 31, 2023. For income tax purposes, the sale of UTXL's equity interests to the Company is intended to be treated as a sale and purchase of assets. Accordingly, the book and tax basis of the acquired assets and liabilities are the same as of the purchase date. The SPA contains customary representations, warranties, covenants, and indemnification provisions. The goodwill recognized represents expected synergies from combining the operations of UTXL with the Company, including enhanced service offerings, as well as other intangible assets that did not meet the criteria for separate recognition. The goodwill is expected to be deductible for tax purposes. The purchase price allocation for the acquisition is preliminary and has been allocated based on estimated fair values of the assets acquired and liabilities assumed at the acquisition date, pending the completion of the valuation of acquired tangible assets, an independent valuation of certain acquired intangible assets, assessment of lease agreements, assessment of certain liabilities, the calculation of deferred taxes based upon the underlying tax basis of assets acquired and liabilities assumed, and assessment of other tax related items. As the Company obtains more information, the preliminary purchase price allocation disclosed below is subject to change. Any future adjustments to the preliminary purchase price allocation, including changes within identifiable intangible assets or estimation uncertainty impacted by market conditions, may impact future net earnings. The purchase price allocation adjustments can be made through the end of the measurement period, which is not to exceed one year from the acquisition date. June 1, 2021 Opening Balance Sheet as Reported at June 30, 2021 Fair value of the consideration transferred $ 37,230 Cash and cash equivalents 8,206 Trade receivables and other current assets 9,451 Property and equipment 54 Identifiable intangible assets 1 22,121 Total assets 39,832 Accounts payable (14,183) Accrued payroll and payroll-related expenses (247) Accrued liabilities (69) Claims accruals – current portion (418) Total liabilities (14,917) Goodwill $ 12,315 1 Includes $19.2 million in customer relationships, $0.3 million in noncompete agreements, and a $2.6 million trade name. Eleos Acquisition On February 1, 2021, pursuant to a membership interest purchase agreement ("MIPA"), the Company, through a wholly owned subsidiary, acquired 79.44% of the issued and outstanding membership interests of Eleos Technologies, LLC ("Eleos"), a Greenville, South Carolina based software provider, specializing in mobile driving platforms, which complement the Company's suite of services. The total purchase price consideration, including cash on hand and net working capital adjustments, consisted of $41.5 million in cash to the sellers at closing, which was funded through cash-on-hand and borrowing on the Revolver on the transaction date. At closing, $4.1 million of the cash consideration was placed in escrow to secure certain of the sellers' indemnification obligations and other items. The MIPA included that both the buyer and sellers would file an election under the Internal Revenue Code Section 754 to adjust the tax basis of the Company's assets and liabilities, with respect to the buyer's purchase of the equity. The MIPA contains customary representations, warranties, covenants, and indemnification provisions for transactions of this nature. The goodwill recognized represents expected synergies from combining the operations of Eleos with the Company, including enhanced service offerings, as well as other intangible assets that did not meet the criteria for separate recognition. The goodwill is expected to be deductible for tax purposes. The purchase price allocation for the acquisition is preliminary and has been allocated based on estimated fair values of the assets acquired and liabilities assumed at the acquisition date, pending the completion of the valuation of acquired tangible assets, an independent valuation of certain acquired intangible assets, assessment of lease agreements, assessment of certain liabilities, the calculation of deferred taxes based upon the underlying tax basis of assets acquired and liabilities assumed, and assessment of other tax related items. As the Company obtains more information, the preliminary purchase price allocation disclosed below is subject to change. Any future adjustments to the preliminary purchase price allocation, including changes within identifiable intangible assets or estimation uncertainty impacted by market conditions, may impact future net earnings. The purchase price allocation adjustments can be made through the end of the measurement period, which is not to exceed one year from the acquisition date. The following table summarizes the fair value of the consideration transferred as of the acquisition date: February 1, 2021 Opening Balance Sheet as Reported at June 30, 2021 Fair value of the consideration transferred $ 41,518 Cash and cash equivalents 2,237 Trade and other receivables 545 Prepaid expenses and other assets 47 Operating lease right-of-use assets 560 Identifiable intangible assets 1 15,850 Total assets 19,239 Accounts payable (156) Accrued payroll and payroll-related expenses (605) Accrued liabilities (1,391) Operating lease liabilities – current and noncurrent portions (560) Other long-term liabilities (475) Total liabilities (3,187) Noncontrolling interest (10,281) Total stockholders' equity (10,281) Goodwill $ 35,747 1 Includes $8.8 million in customer relationships, $0.2 million in noncompete agreements, $3.5 million in internally-developed software, and a $3.4 million trade name. Warehousing Co. Information about the accounting treatment for the acquisition of Warehousing Co., including the details of the transaction, determination of the total fair value consideration, allocation of the purchase price at the end of the measurement period are included in the Company’s Quarterly Report for the quarter ended March 31, 2021. As of June 30, 2021 and December 31, 2020, the remaining estimated contingent consideration was $16.2 million representing the fair value of the remaining annual deferred payments for the calendar year ending December 31, 2021 and the annualized six-month period ending June 30, 2022.

Investments

Investments	6 Months Ended
	Jun. 30, 2021
Schedule of Investments [Abstract]
Investments	Investments Restricted Investments, Held-to-Maturity The following tables present the cost or amortized cost, gross unrealized gains and temporary losses, and estimated fair value of the Company's restricted investments, held-to-maturity: June 30, 2021 Gross Unrealized Cost or Amortized Gains Temporary Estimated Fair Value (In thousands) US corporate securities $ 8,589 $ — $ (3) $ 8,586 Restricted investments, held-to-maturity $ 8,589 $ — $ (3) $ 8,586 December 31, 2020 Gross Unrealized Cost or Amortized Gains Temporary Estimated Fair Value (In thousands) US corporate securities $ 9,001 $ 2 $ (8) $ 8,995 Restricted investments, held-to-maturity $ 9,001 $ 2 $ (8) $ 8,995 As of June 30, 2021, the contractual maturities of the restricted investments, held-to-maturity, were one year or less. There were fourteen securities and sixteen securities that were in an unrealized loss position for less than twelve months as of June 30, 2021 and December 31, 2020, respectively. The Company did not recognize any impairment losses related to its held-to-maturity investments during the quarter or year-to-date periods ended June 30, 2021 or 2020. Embark Convertible Note During the second quarter of 2021, the Company invested $25.0 million in Embark in exchange for a convertible note. The convertible note accrues simple interest on the unpaid principal balance at a rate of 10.0% and is payable on demand any time after April 16, 2022, unless earlier converted into shares of Embark's common stock. The amount outstanding on the convertible note is automatically converted into a number of shares of Embark's common stock upon either the closing of a qualified financing or upon a public event, subject to discounted conversion pricing per share based on a valuation of Embark. On June 22, 2021, Embark and Northern Genesis Acquisition Corp II ("NGA"), a publicly-traded special purpose acquisition company ("SPAC"), entered into a definitive business combination agreement that will result in Embark becoming a publicly listed company. Completion of the transaction is expected to occur in the fourth quarter of 2021 and is subject to approval of NGA stockholders and the satisfaction or waiver of certain other customary closing conditions. Based on the valuation of this public event, the Company estimated that the fair value of this investment was $37.6 million and recognized a $12.6 million gain on the convertible note during the quarter ended June 30, 2021. Refer to Note 15 for additional information regarding fair value measurements of the Company's investments.

Assets Held for Sale

Assets Held for Sale	6 Months Ended
	Jun. 30, 2021
Property, Plant and Equipment [Abstract]
Assets Held For Sale	Assets Held for Sale The Company expects to sell its assets held for sale, which primarily consist of revenue equipment, within the next twelve months. Revenue equipment held for sale totaled $17.6 million and $29.8 million as of June 30, 2021 and December 31, 2020, respectively. Net gains on disposals, including disposals of property and equipment classified as assets held for sale, reported in "Miscellaneous operating expenses" in the condensed consolidated statements of comprehensive income, were: • $15.1 million and $1.7 million for the quarter-to-date periods ended June 30, 2021 and 2020, respectively. The increase in net gains on disposals was primarily due to a stronger market for used revenue equipment during the quarter-to-date period ended June 30, 2021, as compared to the same period in 2020. • $25.6 million and $4.7 million for the year-to-date periods ended June 30, 2021 and 2020, respectively. The increase in net gains on disposals was primarily due to a stronger market for used revenue equipment during the year-to-date period ended June 30, 2021, as compared to the same period in 2020. The Company did not recognize impairment losses related to assets held for sale during the quarters and year-to-date periods ended June 30, 2021. The Company recognized impairment losses related to assets held for sale of $0.4 million during the quarter and year-to-date periods ended June 30, 2020.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	6 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill The changes in the carrying amount of goodwill were as follows: (In thousands) Goodwill, balance at December 31, 2020 $ 2,922,964 Adjustments relating to deferred tax assets (3) Acquisitions 1 48,062 Goodwill, balance at June 30, 2021 $ 2,971,023 1 The goodwill associated with the Eleos and UTXL acquisitions referenced in Note 3 was allocated to the non-reportable and logistics segments, respectively, and is net of purchase price accounting adjustments. The Company did not record any goodwill impairments during the quarter or year-to-date periods ended June 30, 2021 or 2020. Other Intangible Assets Other intangible asset balances were as follows: June 30, 2021 December 31, (In thousands) Definite-lived intangible assets 1 Gross carrying amount $ 929,910 $ 894,597 Accumulated amortization (169,585) (145,852) Definite-lived intangible assets, net 760,325 748,745 Indefinite-lived trade names: Gross carrying amount 643,158 640,500 Intangible assets, net $ 1,403,483 $ 1,389,245 1 The major categories of the Company's definite-lived intangible assets include customer relationships, non-compete agreements, internally-developed software, trade names, and others. Identifiable intangible assets subject to amortization have been recorded at fair value. Intangible assets related to acquisitions other than the 2017 Merger are amortized over a weighted-average amortization period of 17.5 years. The Company's customer relationship intangible assets related to the 2017 Merger are being amortized over a weighted average amortization period of 19.9 years.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Effective Tax Rate — The quarter-to-date June 30, 2021 and June 30, 2020 effective tax rates were 25.3% and 25.0%, respectively. The year-to-date June 30, 2021 and June 30, 2020 effective tax rates were 25.5% and 26.0%, respectively. Valuation Allowance — 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 believes that it is more likely than not that the results of future operations will generate sufficient taxable income to realize the deferred tax assets. Unrecognized Tax Benefits — Management believes it is reasonably possible that a decrease of up to $0.7 million in unrecognized tax benefits relating to federal deductions may be necessary within the next twelve months. Interest and Penalties — Accrued interest and penalties related to unrecognized tax benefits were approximately $0.4 million and $0.3 million as of June 30, 2021 and December 31, 2020, respectively. Tax Examinations — Certain of the Company's subsidiaries are currently under examination by various state jurisdictions for tax years ranging from 2013 to 2019 . 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 2015 remain subject to examination.

Accounts Receivable Securitizat

Accounts Receivable Securitization	6 Months Ended
	Jun. 30, 2021
Transfers and Servicing [Abstract]
Accounts Receivable Securitization	Accounts Receivable Securitization On April 23, 2021, the Company entered into the Fifth Amendment to the Amended and Restated Receivables Sales Agreement ("2021 RSA") which further amended the 2018 RSA. The 2021 RSA is a secured borrowing that is collateralized by the Company's eligible receivables, for which the Company is the servicing agent. The Company's receivable originator subsidiaries sell, on a revolving basis, undivided interests in all of their eligible accounts receivable to Swift Receivables Company II, LLC ("SRCII") who in turn sells a variable percentage ownership in those receivables to the various purchasers. The Company's eligible receivables are included in "Trade receivables, net of allowance for doubtful accounts" in the condensed consolidated balance sheets. As of June 30, 2021, the Company's eligible receivables generally have high credit quality, as determined by the obligor's corporate credit rating. The 2021 RSA is subject to fees, various affirmative and negative covenants, representations and warranties, and default and termination provisions customary for facilities of this type. The Company was in compliance with these covenants as of June 30, 2021. 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. The following table summarizes the key terms of the 2021 RSA and 2018 RSA (dollars in thousands): 2021 RSA 2018 RSA Effective date April 23, 2021 July 11, 2018 Final maturity date April 23, 2024 July 9, 2021 Borrowing capacity $400,000 $325,000 Accordion option 1 $100,000 $175,000 Unused commitment fee rate 2 20 to 40 basis points 20 to 40 basis points Program fees on outstanding balances 3 4 one-month LIBOR + 82.5 basis points one-month LIBOR + 80 to 100 basis points 1 The accordion option increases the maximum borrowing capacity, subject to participation of the purchasers. 2 The 2021 RSA and 2018 RSA commitment fees rate are based on the percentage of the maximum borrowing capacity utilized. 3 Only the rate for the 2018 RSA program fee is subject to the Company's consolidated total net leverage ratio. 4 As identified within the 2021 RSA, the lender can trigger an amendment by identifying and deciding upon a replacement for LIBOR. Availability under the 2021 RSA and 2018 RSA is calculated as follows: 2021 RSA 2018 RSA June 30, 2021 December 31, 2020 (In thousands) Borrowing base, based on eligible receivables $ 400,000 $ 302,700 Less: outstanding borrowings 1 (279,000) (214,000) Less: outstanding letters of credit (65,281) (67,281) Availability under accounts receivable securitization facilities $ 55,719 $ 21,419 1 As of June 30, 2021, outstanding borrowings are included in "Accounts receivable securitization – less current portion" in the condensed consolidated balance sheets and are offset by $0.6 million of deferred loan costs. As of December 31, 2020, outstanding borrowings are included in "Accounts receivable securitization – current portion" in the condensed consolidated balance sheets and are offset by $0.1 million of deferred loan costs . Interest accrued on the aggregate principal balance at a rate of 0.9% and 1.0% as of June 30, 2021 and December 31, 2020, respectively. Program fees and unused commitment fees are recorded in "Interest expense" in the condensed consolidated statements of comprehensive income. The Company incurred accounts receivable securitization program fees of $0.8 million and $0.7 million during the quarter-to-date June 30, 2021 and 2020 periods, respectively. The Company incurred accounts receivable securitization program fees of $1.4 million and $2.1 million during the year-to-date June 30, 2021 and 2020 periods, respectively.

Commitments

Commitments	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments	Commitments Purchase Commitments As of June 30, 2021, the Company had outstanding commitments to purchase revenue equipment of $509.2 million in the remainder of 2021 ($317.3 million of which were tractor commitments) and none thereafter. These purchases may be financed through any combination of operating leases, finance leases, debt, proceeds from sales of existing equipment, and cash flows from operations. As of June 30, 2021, the Company had outstanding commitments to purchase facilities and non-revenue equipment of $36.9 million in the remainder of 2021, $4.6 million in the two-year period 2022 through 2023, $0.8 million in the two-year period 2024 through 2025, and none thereafter. Factors such as costs and opportunities for future terminal expansions may change the amount of such expenditures. As of June 30, 2021, the Company had outstanding commitments for fuel purchases of $14.5 million in the remainder of 2021, and none thereafter. TRP Commitments Since 2003, Knight has entered into partnership agreements with entities that make privately-negotiated equity investments. In these agreements, Knight committed to invest in return for an ownership percentage. During the first quarter of 2021, Knight increased its commitment to invest in TRP Capital Partners V, LP by $10.0 million to $30.0 million, with $26.3 million outstanding as of June 30, 2021. There were no other material changes related to the previously disclosed TRP commitments during the quarter ended June 30, 2021. Embark Commitment On June 23, 2021, the Company entered into a stock subscription agreement with Embark to purchase $25.0 million of Embark's common stock, with $25.0 million outstanding as of June 30, 2021.

Contingencies and Legal Proceed

Contingencies and Legal Proceedings	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Legal Proceedings	Contingencies and Legal Proceedings 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. The Company has made accruals with respect to its legal matters where appropriate, which are included in "Accrued liabilities" in the condensed consolidated balance sheets. The Company has recorded an aggregate accrual of approximately $23.9 million, relating to the Company's outstanding legal proceedings as of June 30, 2021. Based on management's present knowledge of the facts and (in certain cases) advice of outside counsel, management does not believe that loss contingencies arising from pending matters are likely to have a material adverse effect on the Company's overall financial position, operating results, or cash flows after taking into account any existing accruals. However, actual outcomes could be material to the Company's financial position, operating results, or cash flows for any particular period. EMPLOYEE COMPENSATION AND PAY PRACTICES MATTERS CRST Expedited The plaintiff alleges tortious interference with contract and unjust enrichment related to non-competition agreements entered into with certain of its drivers. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in CRST Expedited, Inc. Swift Transportation Co. of Arizona LLC. March 20, 2017 United States District Court for the Northern District of Iowa Recent Developments and Current Status In July 2019, a jury issued an adverse verdict in this lawsuit. The court issued a decision granting in part and denying in part certain motions related to the jury’s verdict. Both parties have appealed the court’s decision. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021. California Wage, Meal, and Rest 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 Recent Developments and Current Status In April 2019, the parties reached settlement of this matter. In January 2020, the court granted final approval of the settlement. Two objectors appealed the court’s decision granting final approval of the settlement. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021. INDEPENDENT CONTRACTOR MATTERS Ninth Circuit Independent Contractor Misclassification Class Action The putative class alleges that Swift misclassified independent contractors as independent contractors, instead of employees, in violation of the Fair Labor Standards Act and various state laws. The lawsuit also raises certain related issues with respect to the lease agreements that certain independent contractors have entered into with Interstate Equipment Leasing, LLC. The putative class seeks unpaid wages, liquidated damages, interest, other costs, and attorneys' fees. 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 In January 2020, the court granted final approval of the settlement in this matter. In March 2020, the Company paid the settlement amount approved by the court. As of June 30, 2021, the Company has accrued for anticipated costs associated with finalizing this matter. 1 Individually and on behalf of all others similarly situated. Other Environmental The Company's tractors and trailers are involved in motor vehicle accidents, experience damage, mechanical failures and cargo issues as an incidental part of its normal ordinary 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 June 30, 2021, the Company's estimate for its total legal liability for all such clean-up and remediation costs was approximately $0.5 million in the aggregate for all current and prior year claims. Self Insurance Automobile Liability, General Liability, and Excess Liability — Effective November 1, 2020, the Company has $100.0 million in excess auto liability ("AL") coverage. Effective November 1, 2019, the Company had $130.0 million in excess auto liability ("AL") coverage. For prior years, Swift and Knight separately maintained varying excess AL and general liability limits. During prior policy periods, Swift AL claims were subject to a $10.0 million self-insured retention ("SIR") per occurrence and Knight AL claims were subject to a $1.0 million to $3.0 million SIR per occurrence. Additionally, Knight carried a $2.5 million aggregate deductible for any loss or losses within the $5.0 million excess of $5.0 million layer of coverage. Effective March 1, 2020, Knight and Swift retain the same $10.0 million SIR per occurrence. Cargo Damage and Loss — The Company is insured against cargo damage and loss with liability limits of $2.0 million per truck or trailer with a $10.0 million limit per occurrence. Workers' Compensation and Employers' Liability — The Company is self-insured for workers' compensation coverage. Swift maintains statutory coverage limits, subject to a $5.0 million SIR for each accident or disease. Effective March 1, 2019, Knight maintains statutory coverage limits, subject to a $2.0 million SIR for each accident or disease.

Share Repurchase Plan

Share Repurchase Plan	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Share Repurchase Plan	Share Repurchase Plan On November 30, 2020, the Company announced that the Board approved the repurchase of up to $250.0 million worth of the Company's outstanding common stock (the "2020 Knight-Swift Share Repurchase Plan"). With the adoption of the 2020 Knight-Swift Share Repurchase Plan, the Company terminated the previous share repurchase plan, which had approximately $54.1 million of authorized purchases remaining upon termination. The following table presents the Company's repurchases of its common stock under the respective share repurchase plans, excluding advisory fees: Share Repurchase Plan Quarter-to-Date June 30, 2021 Year-to-Date June 30, 2021 Board Approval Date Authorized Amount Shares Amount Shares Amount (shares and dollars in thousands) November 24, 2020 1 $250,000 — $ — 1,303 $ 53,661 Quarter-to-Date June 30, 2020 Year-to-Date June 30, 2020 May 30, 2019 $250,000 — $ — 1,139 $ 34,630 1 $196.3 million and $250.0 million remained available under the 2020 Knight-Swift Share Repurchase Plan as of June 30, 2021 and December 31, 2020, respectively.

Weighted Average Shares Outstan

Weighted Average Shares Outstanding	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Weighted Average Shares Outstanding	Weighted Average Shares Outstanding Earnings per share, basic and diluted, as presented in the condensed consolidated statements of comprehensive income, are calculated by dividing net income attributable to Knight-Swift 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: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 (In thousands) Basic weighted average common shares outstanding 165,577 169,948 165,751 170,283 Dilutive effect of equity awards 1,008 676 999 675 Diluted weighted average common shares outstanding 166,585 170,624 166,750 170,958 Anti-dilutive shares excluded from diluted earnings per share 1 31 365 47 329 1 Shares were excluded from the dilutive-effect calculation because the outstanding awards' exercise prices were greater than the average market price of the Company's common stock for the periods presented.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The following table presents Knight-Swift's transactions with companies controlled by and/or affiliated with its related parties: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift (In thousands) Freight Services: Central Freight Lines 1 $ — $ — $ 1,020 $ — $ — $ — $ 7,836 $ — SME Industries 1 — — 28 — — — 28 — Total $ — $ — $ 1,048 $ — $ — $ — $ 7,864 $ — Facility and Equipment Leases: Central Freight Lines 1 $ — $ — $ 23 $ 93 $ — $ — $ 23 $ 185 Other Affiliates 1 — 88 4 36 — 145 9 109 Total $ — $ 88 $ 27 $ 129 $ — $ 145 $ 32 $ 294 Other Services: Central Freight Lines 1 $ — $ — $ — $ — $ — $ — $ 15 $ — DPF Mobile 1 — — — 19 — — — 31 Other Affiliates 1 7 9 10 — 13 18 19 — Total $ 7 $ 9 $ 10 $ 19 $ 13 $ 18 $ 34 $ 31 1 Entities affiliated with former Board member Jerry Moyes include Central Freight Lines, SME Industries, Compensi Services, and DPF Mobile. "Other affiliates" includes entities that are associated with various board members and executives and require approval by the Board prior to completing transactions. Transactions with these entities generally include freight services, facility and equipment leases, equipment sales, and other services. • Freight Services Provided by Knight-Swift — The Company charges each of these companies for transportation services. • Freight Services Received by Knight-Swift — Transportation services received from Central Freight Lines represent less-than-truckload freight services rendered to haul parts and equipment to Company shop locations. • Other Services Provided by Knight-Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services. • Other Services Received by Knight-Swift — Consulting fees, diesel particulate filter cleaning, sales of various parts and tractor accessories, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company. During the quarter ended September 30, 2020, the ownership percentage of Jerry Moyes and related affiliates fell below the threshold requiring related party disclosure. The amounts included in this Note 13 pertain to transactions that occurred prior to the date that the ownership percentage changed. Receivables and payables pertaining to related party transactions were: June 30, 2021 December 31, 2020 Receivable Payable Receivable Payable (In thousands) Central Freight Lines $ — $ — $ 133 $ — DPF Mobile — — — 41 Other Affiliates 1,792 20 2 10 Total $ 1,792 $ 20 $ 135 $ 51

Information by Segment and Geog

Information by Segment and Geography	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Information by Segment and Geography	Information by Segment and Geography Segment Information The Company has three reportable segments: Trucking, Logistics, and Intermodal, as well as the non-reportable segments, discussed below. Based on how economic factors affect the nature, amount, timing, and uncertainty of revenue or cash flows, the Company disaggregates revenues by reportable segment for the purposes of applying the ASC Topic 606 guidance. The Company's twenty-two operating segments are structured around the types of transportation service offerings provided to our customers, as well as the equipment utilized. In addition, the operating segments may be further distinguished by the Company’s respective brands. The Company aggregated these various operating segments into the three reportable segments discussed below based on similarities with both their qualitative and economic characteristics. Trucking The Trucking reportable segment is comprised of nine trucking operating segments that provide similar transportation services to our customers utilizing similar transportation equipment over both irregular (one-way movement) and/or dedicated routes. The Trucking reportable segment consists of irregular route and dedicated, refrigerated, expedited, flatbed, and cross-border operations. Logistics The Logistics reportable segment is comprised of six logistics operating segments that provide similar transportation services to our customers and primarily consist of brokerage and other freight management services utilizing third-party transportation providers and their equipment. Intermodal The Intermodal reportable segment is comprised of two intermodal operating segments that provide similar transportation services to our customers. These transportation services include arranging the movement of customers' freight through third-party intermodal rail services on the Company’s trailing equipment (trailers on flat cars and rail containers), as well as drayage services to transport loads between the railheads and customer locations. Non-reportable The non-reportable segments include five operating segments that consist of support services provided to the Company's customers and independent contractors (including repair and maintenance shop services, equipment leasing, warranty services, and insurance), trailer parts manufacturing, warehousing, and certain driving academy activities, as well as certain corporate expenses (such as legal settlements and accruals, certain impairments, and amortization of intangibles related to the 2017 Merger and various acquisitions). Intersegment Eliminations Certain operating segments provide transportation and related services for other affiliates outside of their segments. For certain operating segments, such services are billed at cost, and no profit is earned. For the other operating segments, revenues for such services are based on negotiated rates, 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 Knight-Swift's consolidated results. The following tables present the Company's financial information by segment: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Revenue: (In thousands) Trucking $ 985,858 $ 879,369 $ 1,948,805 $ 1,798,430 Logistics 166,737 70,104 285,624 149,302 Intermodal 115,378 82,820 222,444 177,551 Subtotal $ 1,267,973 $ 1,032,293 $ 2,456,873 $ 2,125,283 Non-reportable segments 66,795 45,289 117,464 91,531 Intersegment eliminations (19,067) (16,884) (35,622) (31,318) Total revenue $ 1,315,701 $ 1,060,698 $ 2,538,715 $ 2,185,496 Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Operating income (loss): (In thousands) Trucking $ 168,457 $ 107,788 $ 326,940 $ 215,122 Logistics 14,356 3,038 21,933 6,757 Intermodal 5,812 (4,475) 9,269 (7,212) Subtotal $ 188,625 $ 106,351 $ 358,142 $ 214,667 Non-reportable segments 2,490 (4,184) (4,768) (10,381) Operating income $ 191,115 $ 102,167 $ 353,374 $ 204,286 Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Depreciation and amortization of property and equipment: (In thousands) Trucking $ 105,206 $ 97,555 $ 207,091 $ 191,103 Logistics 289 207 497 414 Intermodal 3,940 3,606 7,758 7,094 Subtotal $ 109,435 $ 101,368 $ 215,346 $ 198,611 Non-reportable segments 14,171 13,233 28,175 26,211 Depreciation and amortization of property and equipment $ 123,606 $ 114,601 $ 243,521 $ 224,822 Geographical Information In the aggregate, total revenue from the Company's foreign operations was less than 5.0% of consolidated total revenue for the quarter and year-to-date periods ended June 30, 2021 and 2020. Additionally, long-lived assets on the Company's foreign subsidiary balance sheets were less than 5.0% of consolidated total assets as of June 30, 2021 and December 31, 2020.

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 30, 2021
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 June 30, 2021 and December 31, 2020, the amounts that will actually be realized or paid at settlement or maturity of the instruments in the future could be significantly different. The estimated fair values of the Company's financial instruments 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 management'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, Held-to-Maturity — The estimated fair value of the Company's restricted investments, held-to-maturity, is based on quoted prices in active markets that are readily and regularly obtainable. See Note 4 for additional disclosures regarding restricted investments, held-to-maturity. Convertible Notes — The estimated fair value of the Company's convertible note is based on probability weighted discounted cash flow analysis of the corresponding pay-off/redemption. Equity Method Investments — The estimated fair value of the Company's equity method investments are privately negotiated investments. The carrying amount of these investments approximates the fair value. Equity Securities — The estimated fair value of the Company's investments in equity securities is based on quoted prices in active markets that are readily and regularly obtainable. Debt Instruments and Leases — For notes payable under the Revolver and the 2017 Term Loan, fair value approximates the carrying value due to the variable interest rate. The carrying values of the 2021 RSA and 2018 RSA approximate fair value, as the underlying receivables are short-term in nature and only eligible receivables (such as those with high credit ratings) are qualified to secure the borrowed amounts. For finance and operating lease liabilities, the carrying value approximates the fair value, as the Company's finance and operating lease liabilities are structured to amortize in a manner similar to the depreciation of the underlying assets. Contingent Consideration — The estimated fair value of the Company's contingent consideration owed to sellers is calculated using applicable models and inputs for each acquiree. Other — Cash and cash equivalents, restricted cash, net accounts receivable, income tax refund receivable, and accounts payable represent financial instruments for which the carrying amount approximates fair value, as they are short-term in nature. These instruments are accordingly excluded from the disclosures below. All remaining balance sheet amounts excluded from the 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 major categories of financial assets and liabilities: June 30, 2021 December 31, 2020 Carrying Estimated Carrying Estimated (In thousands) Financial Assets: Restricted investments, held-to-maturity 1 $ 8,589 $ 8,586 $ 9,001 $ 8,995 Equity method investments 2 81,237 81,237 77,562 77,562 Investments in equity securities 3 19,707 19,707 18,675 18,675 Convertible note 4 37,631 37,631 — — Financial Liabilities: 2017 Term Loan, due October 2022 5 $ 299,219 $ 300,000 $ 298,907 $ 300,000 2018 RSA, due July 2021 6 — — 213,918 214,000 2021 RSA, due April 2024 7 278,372 279,000 — — Revolver, due October 2022 55,000 55,000 210,000 210,000 Contingent consideration associated with acquisitions 8 21,200 21,200 16,200 16,200 1 Refer to Note 4 for the differences between the carrying amounts and estimated fair values of the Company's restricted investments, held-to-maturity. 2 Net equity method investment balances included in "Other long-term assets" in the condensed consolidated balance sheets. 3 The investments are carried at fair value and are included in "Other long-term assets" on the condensed consolidated balance sheets. 4 The loan is carried at fair value and is included in "Other current assets" in the condensed consolidated balance sheets. 5 The carrying amount of the 2017 Term Loan is included in "Finance lease liabilities and long-term debt – less current portion," on the condensed consolidated balance sheets and is net of $0.8 million and $1.1 million in deferred loan costs as of June 30, 2021 and December 31, 2020, respectively. 6 The carrying amount of the 2018 RSA is included in " Accounts receivable securitization – current portion ," on the condensed consolidated balance sheets and is net of $0.1 million in deferred loan costs as of December 31, 2020 . 7 The carrying amount of the 2021 RSA is included in " Accounts receivable securitization – less current portion ," on the condensed consolidated balance sheets and is net of $0.6 million in deferred loan costs as of June 30, 2021 . 8 The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets. Recurring Fair Value Measurements (Assets) — The following table depicts the level in the fair value hierarchy of the inputs used to estimate the fair value of assets measured on a recurring basis as of June 30, 2021 and December 31, 2020 : Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Unrealized Gain Position (In thousands) As of June 30, 2021 Convertible note 1 $ 37,631 $ — $ — $ 37,631 $ 12,631 Investments in equity securities 2 $ 19,707 $ 19,707 $ — $ — $ 8,126 As of December 31, 2020 Investments in equity securities 3 $ 18,675 $ 18,675 $ — $ — $ 3,553 1 The Company recognized $12.6 million of unrealized gains on the convertible note for the quarter and year-to-date periods ended June 30, 2021, which is included within "Other income, net" within the condensed consolidated statement of comprehensive income. The fair value of the note was determined using a discounted cash flow analysis based on the probability of exit event options and exit event dates. 2 Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2021, the Company recognized $1.5 million in net losses on these investments in equity securities, consisting of $2.3 million in unrealized losses and $0.8 million in realized gains. • During the year-to-date period ended June 30, 2021, the Company recognized $8.9 million in gains on these investments in equity securities, consisting of $4.6 million in unrealized gains and $4.3 million in realized gains. 3 Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2020, the Company recognized $7.6 million in unrealized gains on these investments in equity securities. • During the year-to-date period ended June 30, 2020, the Company recognized $2.5 million in unrealized gains on these investments in equity securities. Recurring Fair Value Measurements (Liabilities) — The following table depicts the level in the fair value hierarchy of the inputs used to estimate the fair value of liabilities measured on a recurring basis as of June 30, 2021 and December 31, 2020: Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Gain (Loss) (In thousands) As of June 30, 2021 Contingent consideration associated with acquisitions 1 $ 21,200 $ — $ — $ 21,200 $ — As of December 31, 2020 Contingent consideration associated with acquisition 2 $ 16,200 $ — $ — $ 16,200 $ (6,730) 1 The Company did not recognize any gains (losses) during the quarter or year-to-date periods ended June 30, 2021 related to the revaluation of these liabilities. Refer to Note 3 for information regarding the components of these liabilities. 2 During the fourth quarter of 2020, the Company increased the estimated fair value of the remaining contingent consideration representing the final two annual payments, resulting in a $6.7 million fair value adjustment of the deferred earnout, which was recorded in “Miscellaneous operating expenses” in the consolidated statement of comprehensive income. The Company did not recognize any losses during the quarter and year-to-date periods ended June 30, 2020. Nonrecurring Fair Value Measurements (Assets) — As of June 30, 2021, the Company had no major categories of assets estimated at fair value that were measured on a nonrecurring basis. The following table depicts the level in the fair value hierarchy of the inputs used to estimate fair value of assets measured on a nonrecurring basis as of December 31, 2020: Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Loss (In thousands) As of December 31, 2020 Equipment 1 5,851 — 5,851 — (5,335) 1 Reflects the non-cash impairment of certain alternative fuel technology (within the non-reportable segments) and certain revenue equipment held for sale (within the Trucking segment). The Company recognized $0.4 million and $1.3 million of impairments during the quarter and year-to-date periods ended June 30, 2020. Nonrecurring Fair Value Measurements (Liabilities) — As of June 30, 2021 and December 31, 2020, the Company had no major categories of liabilities estimated at fair value that were measured on a nonrecurring basis.

Introduction and Basis of Pre_2

Introduction and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	In management's opinion, these condensed consolidated financial statements were prepared in accordance with GAAP and include all adjustments necessary (consisting of normal recurring adjustments) for the fair statement of the periods presented.

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2021
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	June 1, 2021 Opening Balance Sheet as Reported at June 30, 2021 Fair value of the consideration transferred $ 37,230 Cash and cash equivalents 8,206 Trade receivables and other current assets 9,451 Property and equipment 54 Identifiable intangible assets 1 22,121 Total assets 39,832 Accounts payable (14,183) Accrued payroll and payroll-related expenses (247) Accrued liabilities (69) Claims accruals – current portion (418) Total liabilities (14,917) Goodwill $ 12,315 1 Includes $19.2 million in customer relationships, $0.3 million in noncompete agreements, and a $2.6 million trade name. The following table summarizes the fair value of the consideration transferred as of the acquisition date: February 1, 2021 Opening Balance Sheet as Reported at June 30, 2021 Fair value of the consideration transferred $ 41,518 Cash and cash equivalents 2,237 Trade and other receivables 545 Prepaid expenses and other assets 47 Operating lease right-of-use assets 560 Identifiable intangible assets 1 15,850 Total assets 19,239 Accounts payable (156) Accrued payroll and payroll-related expenses (605) Accrued liabilities (1,391) Operating lease liabilities – current and noncurrent portions (560) Other long-term liabilities (475) Total liabilities (3,187) Noncontrolling interest (10,281) Total stockholders' equity (10,281) Goodwill $ 35,747 1 Includes $8.8 million in customer relationships, $0.2 million in noncompete agreements, $3.5 million in internally-developed software, and a $3.4 million trade name.

Restricted Investments, Held-to

Restricted Investments, Held-to-Maturity (Tables)	6 Months Ended
	Jun. 30, 2021
Schedule of Investments [Abstract]
Schedule of Restricted Investments, Held-to-Maturity	The following tables present the cost or amortized cost, gross unrealized gains and temporary losses, and estimated fair value of the Company's restricted investments, held-to-maturity: June 30, 2021 Gross Unrealized Cost or Amortized Gains Temporary Estimated Fair Value (In thousands) US corporate securities $ 8,589 $ — $ (3) $ 8,586 Restricted investments, held-to-maturity $ 8,589 $ — $ (3) $ 8,586 December 31, 2020 Gross Unrealized Cost or Amortized Gains Temporary Estimated Fair Value (In thousands) US corporate securities $ 9,001 $ 2 $ (8) $ 8,995 Restricted investments, held-to-maturity $ 9,001 $ 2 $ (8) $ 8,995

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The changes in the carrying amount of goodwill were as follows: (In thousands) Goodwill, balance at December 31, 2020 $ 2,922,964 Adjustments relating to deferred tax assets (3) Acquisitions 1 48,062 Goodwill, balance at June 30, 2021 $ 2,971,023
Schedule of Intangible Assets, net	Other intangible asset balances were as follows: June 30, 2021 December 31, (In thousands) Definite-lived intangible assets 1 Gross carrying amount $ 929,910 $ 894,597 Accumulated amortization (169,585) (145,852) Definite-lived intangible assets, net 760,325 748,745 Indefinite-lived trade names: Gross carrying amount 643,158 640,500 Intangible assets, net $ 1,403,483 $ 1,389,245

Accounts Receivable Securitiz_2

Accounts Receivable Securitization (Tables)	6 Months Ended
	Jun. 30, 2021
Transfers and Servicing [Abstract]
Schedule of Servicing Liabilities at Fair Value [Table Text Block]	The following table summarizes the key terms of the 2021 RSA and 2018 RSA (dollars in thousands): 2021 RSA 2018 RSA Effective date April 23, 2021 July 11, 2018 Final maturity date April 23, 2024 July 9, 2021 Borrowing capacity $400,000 $325,000 Accordion option 1 $100,000 $175,000 Unused commitment fee rate 2 20 to 40 basis points 20 to 40 basis points Program fees on outstanding balances 3 4 one-month LIBOR + 82.5 basis points one-month LIBOR + 80 to 100 basis points 1 The accordion option increases the maximum borrowing capacity, subject to participation of the purchasers. 2 The 2021 RSA and 2018 RSA commitment fees rate are based on the percentage of the maximum borrowing capacity utilized. 3 Only the rate for the 2018 RSA program fee is subject to the Company's consolidated total net leverage ratio. 4 As identified within the 2021 RSA, the lender can trigger an amendment by identifying and deciding upon a replacement for LIBOR. Availability under the 2021 RSA and 2018 RSA is calculated as follows: 2021 RSA 2018 RSA June 30, 2021 December 31, 2020 (In thousands) Borrowing base, based on eligible receivables $ 400,000 $ 302,700 Less: outstanding borrowings 1 (279,000) (214,000) Less: outstanding letters of credit (65,281) (67,281) Availability under accounts receivable securitization facilities $ 55,719 $ 21,419 1 As of June 30, 2021, outstanding borrowings are included in "Accounts receivable securitization – less current portion" in the condensed consolidated balance sheets and are offset by $0.6 million of deferred loan costs. As of December 31, 2020, outstanding borrowings are included in "Accounts receivable securitization – current portion" in the condensed consolidated balance sheets and are offset by $0.1 million of deferred loan costs . Interest accrued on the aggregate principal balance at a rate of 0.9% and 1.0% as of June 30, 2021 and December 31, 2020, respectively.

Contingencies and Legal Proce_2

Contingencies and Legal Proceedings (Tables)	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Loss Contingencies by Contingency	EMPLOYEE COMPENSATION AND PAY PRACTICES MATTERS CRST Expedited The plaintiff alleges tortious interference with contract and unjust enrichment related to non-competition agreements entered into with certain of its drivers. Plaintiff(s) Defendant(s) Date instituted Court or agency currently pending in CRST Expedited, Inc. Swift Transportation Co. of Arizona LLC. March 20, 2017 United States District Court for the Northern District of Iowa Recent Developments and Current Status In July 2019, a jury issued an adverse verdict in this lawsuit. The court issued a decision granting in part and denying in part certain motions related to the jury’s verdict. Both parties have appealed the court’s decision. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021. California Wage, Meal, and Rest 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 Recent Developments and Current Status In April 2019, the parties reached settlement of this matter. In January 2020, the court granted final approval of the settlement. Two objectors appealed the court’s decision granting final approval of the settlement. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021. INDEPENDENT CONTRACTOR MATTERS Ninth Circuit Independent Contractor Misclassification Class Action The putative class alleges that Swift misclassified independent contractors as independent contractors, instead of employees, in violation of the Fair Labor Standards Act and various state laws. The lawsuit also raises certain related issues with respect to the lease agreements that certain independent contractors have entered into with Interstate Equipment Leasing, LLC. The putative class seeks unpaid wages, liquidated damages, interest, other costs, and attorneys' fees. 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 In January 2020, the court granted final approval of the settlement in this matter. In March 2020, the Company paid the settlement amount approved by the court. As of June 30, 2021, the Company has accrued for anticipated costs associated with finalizing this matter. 1 Individually and on behalf of all others similarly situated.

Share Repurchase Plan (Tables)

Share Repurchase Plan (Tables)	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Schedule of Share Repurchases	The following table presents the Company's repurchases of its common stock under the respective share repurchase plans, excluding advisory fees: Share Repurchase Plan Quarter-to-Date June 30, 2021 Year-to-Date June 30, 2021 Board Approval Date Authorized Amount Shares Amount Shares Amount (shares and dollars in thousands) November 24, 2020 1 $250,000 — $ — 1,303 $ 53,661 Quarter-to-Date June 30, 2020 Year-to-Date June 30, 2020 May 30, 2019 $250,000 — $ — 1,139 $ 34,630 1 $196.3 million and $250.0 million remained available under the 2020 Knight-Swift Share Repurchase Plan as of June 30, 2021 and December 31, 2020, respectively.

Weighted Average Shares Outst_2

Weighted Average Shares Outstanding (Tables)	6 Months Ended
	Jun. 30, 2021
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: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 (In thousands) Basic weighted average common shares outstanding 165,577 169,948 165,751 170,283 Dilutive effect of equity awards 1,008 676 999 675 Diluted weighted average common shares outstanding 166,585 170,624 166,750 170,958 Anti-dilutive shares excluded from diluted earnings per share 1 31 365 47 329 1 Shares were excluded from the dilutive-effect calculation because the outstanding awards' exercise prices were greater than the average market price of the Company's common stock for the periods presented.

Related Party Transactions (Tab

Related Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	The following table presents Knight-Swift's transactions with companies controlled by and/or affiliated with its related parties: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift Provided by Knight-Swift Received by Knight-Swift (In thousands) Freight Services: Central Freight Lines 1 $ — $ — $ 1,020 $ — $ — $ — $ 7,836 $ — SME Industries 1 — — 28 — — — 28 — Total $ — $ — $ 1,048 $ — $ — $ — $ 7,864 $ — Facility and Equipment Leases: Central Freight Lines 1 $ — $ — $ 23 $ 93 $ — $ — $ 23 $ 185 Other Affiliates 1 — 88 4 36 — 145 9 109 Total $ — $ 88 $ 27 $ 129 $ — $ 145 $ 32 $ 294 Other Services: Central Freight Lines 1 $ — $ — $ — $ — $ — $ — $ 15 $ — DPF Mobile 1 — — — 19 — — — 31 Other Affiliates 1 7 9 10 — 13 18 19 — Total $ 7 $ 9 $ 10 $ 19 $ 13 $ 18 $ 34 $ 31 1 Entities affiliated with former Board member Jerry Moyes include Central Freight Lines, SME Industries, Compensi Services, and DPF Mobile. "Other affiliates" includes entities that are associated with various board members and executives and require approval by the Board prior to completing transactions. Transactions with these entities generally include freight services, facility and equipment leases, equipment sales, and other services. • Freight Services Provided by Knight-Swift — The Company charges each of these companies for transportation services. • Freight Services Received by Knight-Swift — Transportation services received from Central Freight Lines represent less-than-truckload freight services rendered to haul parts and equipment to Company shop locations. • Other Services Provided by Knight-Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services. • Other Services Received by Knight-Swift — Consulting fees, diesel particulate filter cleaning, sales of various parts and tractor accessories, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company. During the quarter ended September 30, 2020, the ownership percentage of Jerry Moyes and related affiliates fell below the threshold requiring related party disclosure. The amounts included in this Note 13 pertain to transactions that occurred prior to the date that the ownership percentage changed. Receivables and payables pertaining to related party transactions were: June 30, 2021 December 31, 2020 Receivable Payable Receivable Payable (In thousands) Central Freight Lines $ — $ — $ 133 $ — DPF Mobile — — — 41 Other Affiliates 1,792 20 2 10 Total $ 1,792 $ 20 $ 135 $ 51

Information by Segment and Ge_2

Information by Segment and Geography (Tables)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Summary Of Financial Information By Segments	The following tables present the Company's financial information by segment: Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Revenue: (In thousands) Trucking $ 985,858 $ 879,369 $ 1,948,805 $ 1,798,430 Logistics 166,737 70,104 285,624 149,302 Intermodal 115,378 82,820 222,444 177,551 Subtotal $ 1,267,973 $ 1,032,293 $ 2,456,873 $ 2,125,283 Non-reportable segments 66,795 45,289 117,464 91,531 Intersegment eliminations (19,067) (16,884) (35,622) (31,318) Total revenue $ 1,315,701 $ 1,060,698 $ 2,538,715 $ 2,185,496 Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Operating income (loss): (In thousands) Trucking $ 168,457 $ 107,788 $ 326,940 $ 215,122 Logistics 14,356 3,038 21,933 6,757 Intermodal 5,812 (4,475) 9,269 (7,212) Subtotal $ 188,625 $ 106,351 $ 358,142 $ 214,667 Non-reportable segments 2,490 (4,184) (4,768) (10,381) Operating income $ 191,115 $ 102,167 $ 353,374 $ 204,286 Quarter-to-Date June 30, Year-to-Date June 30, 2021 2020 2021 2020 Depreciation and amortization of property and equipment: (In thousands) Trucking $ 105,206 $ 97,555 $ 207,091 $ 191,103 Logistics 289 207 497 414 Intermodal 3,940 3,606 7,758 7,094 Subtotal $ 109,435 $ 101,368 $ 215,346 $ 198,611 Non-reportable segments 14,171 13,233 28,175 26,211 Depreciation and amortization of property and equipment $ 123,606 $ 114,601 $ 243,521 $ 224,822

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value by Balance Sheet Grouping	The following table presents the carrying amounts and estimated fair values of the Company's major categories of financial assets and liabilities: June 30, 2021 December 31, 2020 Carrying Estimated Carrying Estimated (In thousands) Financial Assets: Restricted investments, held-to-maturity 1 $ 8,589 $ 8,586 $ 9,001 $ 8,995 Equity method investments 2 81,237 81,237 77,562 77,562 Investments in equity securities 3 19,707 19,707 18,675 18,675 Convertible note 4 37,631 37,631 — — Financial Liabilities: 2017 Term Loan, due October 2022 5 $ 299,219 $ 300,000 $ 298,907 $ 300,000 2018 RSA, due July 2021 6 — — 213,918 214,000 2021 RSA, due April 2024 7 278,372 279,000 — — Revolver, due October 2022 55,000 55,000 210,000 210,000 Contingent consideration associated with acquisitions 8 21,200 21,200 16,200 16,200 1 Refer to Note 4 for the differences between the carrying amounts and estimated fair values of the Company's restricted investments, held-to-maturity. 2 Net equity method investment balances included in "Other long-term assets" in the condensed consolidated balance sheets. 3 The investments are carried at fair value and are included in "Other long-term assets" on the condensed consolidated balance sheets. 4 The loan is carried at fair value and is included in "Other current assets" in the condensed consolidated balance sheets. 5 The carrying amount of the 2017 Term Loan is included in "Finance lease liabilities and long-term debt – less current portion," on the condensed consolidated balance sheets and is net of $0.8 million and $1.1 million in deferred loan costs as of June 30, 2021 and December 31, 2020, respectively. 6 The carrying amount of the 2018 RSA is included in " Accounts receivable securitization – current portion ," on the condensed consolidated balance sheets and is net of $0.1 million in deferred loan costs as of December 31, 2020 . 7 The carrying amount of the 2021 RSA is included in " Accounts receivable securitization – less current portion ," on the condensed consolidated balance sheets and is net of $0.6 million in deferred loan costs as of June 30, 2021 . 8 The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets.
Recurring Fair Value Measurements (Assets)	The following table depicts the level in the fair value hierarchy of the inputs used to estimate the fair value of assets measured on a recurring basis as of June 30, 2021 and December 31, 2020 : Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Unrealized Gain Position (In thousands) As of June 30, 2021 Convertible note 1 $ 37,631 $ — $ — $ 37,631 $ 12,631 Investments in equity securities 2 $ 19,707 $ 19,707 $ — $ — $ 8,126 As of December 31, 2020 Investments in equity securities 3 $ 18,675 $ 18,675 $ — $ — $ 3,553 1 The Company recognized $12.6 million of unrealized gains on the convertible note for the quarter and year-to-date periods ended June 30, 2021, which is included within "Other income, net" within the condensed consolidated statement of comprehensive income. The fair value of the note was determined using a discounted cash flow analysis based on the probability of exit event options and exit event dates. 2 Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2021, the Company recognized $1.5 million in net losses on these investments in equity securities, consisting of $2.3 million in unrealized losses and $0.8 million in realized gains. • During the year-to-date period ended June 30, 2021, the Company recognized $8.9 million in gains on these investments in equity securities, consisting of $4.6 million in unrealized gains and $4.3 million in realized gains. 3 Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2020, the Company recognized $7.6 million in unrealized gains on these investments in equity securities. • During the year-to-date period ended June 30, 2020, the Company recognized $2.5 million in unrealized gains on these investments in equity securities.
Recurring Fair Value Measurements (Liabilities)	The following table depicts the level in the fair value hierarchy of the inputs used to estimate the fair value of liabilities measured on a recurring basis as of June 30, 2021 and December 31, 2020: Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Gain (Loss) (In thousands) As of June 30, 2021 Contingent consideration associated with acquisitions 1 $ 21,200 $ — $ — $ 21,200 $ — As of December 31, 2020 Contingent consideration associated with acquisition 2 $ 16,200 $ — $ — $ 16,200 $ (6,730) 1 The Company did not recognize any gains (losses) during the quarter or year-to-date periods ended June 30, 2021 related to the revaluation of these liabilities. Refer to Note 3 for information regarding the components of these liabilities. 2 During the fourth quarter of 2020, the Company increased the estimated fair value of the remaining contingent consideration representing the final two annual payments, resulting in a $6.7 million fair value adjustment of the deferred earnout, which was recorded in “Miscellaneous operating expenses” in the consolidated statement of comprehensive income. The Company did not recognize any losses during the quarter and year-to-date periods ended June 30, 2020.
Nonrecurring Fair Value Measurements (Assets)	The following table depicts the level in the fair value hierarchy of the inputs used to estimate fair value of assets measured on a nonrecurring basis as of December 31, 2020: Fair Value Measurements at Reporting Date Using: Estimated Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Loss (In thousands) As of December 31, 2020 Equipment 1 5,851 — 5,851 — (5,335)

Introduction and Description of

Introduction and Description of Business (Details)	6 Months Ended
	Jun. 30, 2021VehicleSegment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operational tractors in fleet	18,129
Number of company tractors	16,225
Number of independent contractor tractors	1,904
Number of trailers	60,382
Number of intermodal tractors	605
Number of intermodal containers	10,844
Number of reportable segments | Segment	3

Acquisitions - ACT (Details)

Acquisitions - ACT (Details) - Subsequent Event [Member] - USD ($) $ in Thousands	Jul. 06, 2021	Jul. 05, 2021
Business Acquisition [Line Items]
Subsequent Event, Date		Jul. 5, 2021
Fair value of the consideration transferred		$ 1,310,000
Business Combination, Consideration Transferred, Liabilities Incurred		$ 36,700
ACT
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
2021 Term Loan
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,200,000
Program fees on outstanding balances	BSBY rate (Bloomberg Short-term Bank Yield index)
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Cash paid for acquisition [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		$ 1,300,000
Equity transferred in acquisition
Business Acquisition [Line Items]
Fair value of the consideration transferred		$ 10,000

Acquisitions - UTXL (Details)

Acquisitions - UTXL (Details) - USD ($) $ in Thousands		Jun. 01, 2021	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability	[1]		$ 21,200	$ 16,200
UTXL [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Jun. 1, 2021
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Fair value of the consideration transferred		$ 37,230
Cash paid for acquisition [Member] | UTXL [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		32,200
Escrow For Sellers Indemnification Obligations [Member] | UTXL [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		2,250
Contingent consideration (annual payment) [Member] | UTXL [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability, Current		2,500
Contingent consideration (total payment) [Member] | UTXL [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability		$ 5,000
[1]	The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets.

Acquisitions - Allocation of Pu

Acquisitions - Allocation of Purchase Consideration - UTXL (Details) - USD ($) $ in Thousands		Jun. 01, 2021	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill			$ 2,971,023	$ 2,922,964
UTXL [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		$ 37,230
Cash and cash equivalents		8,206
Trade receivables and other current assets		9,451
Property and equipment		54
Identifiable intangible assets 1	[1]	22,121
Total assets		39,832
Accounts payable		(14,183)
Accrued payroll and payroll-related expenses		(247)
Accrued liabilities		(69)
Claims accruals – current portion		(418)
Total liabilities		(14,917)
Goodwill		12,315
Trade name		2,600
Customer relationships [Member] | UTXL [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets		19,200
Noncompete agreements [Member] | UTXL [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets		$ 300
[1]	Includes $19.2 million in customer relationships, $0.3 million in noncompete agreements, and a $2.6 million trade name.

Acquisitions - Eleos (Details)

Acquisitions - Eleos (Details) - Eleos [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Feb. 01, 2021
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Feb. 1, 2021
Business Acquisition, Percentage of Voting Interests Acquired		79.44%
Fair value of the consideration transferred	$ 41,518	$ 41,500
Escrow For Sellers Indemnification Obligations [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		$ 4,100

Acquisitions - Allocation of _2

Acquisitions - Allocation of Purchase Consideration - Eleos (Details) - USD ($) $ in Thousands		Jun. 30, 2021	Feb. 01, 2021	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Noncontrolling interest				$ (10,281)
Goodwill		$ 2,971,023		2,971,023	$ 2,922,964
Eleos [Member]
Business Acquisition [Line Items]
Fair value of the consideration transferred		41,518	$ 41,500
Cash and cash equivalents		2,237		2,237
Trade and other receivables		545		545
Prepaid expenses and other assets		47		47
Operating lease right-of-use assets		560		560
Identifiable intangible assets 1	[1]	15,850		15,850
Total assets		19,239		19,239
Accounts payable		(156)		(156)
Accrued payroll and payroll-related expenses		(605)		(605)
Accrued liabilities		(1,391)		(1,391)
Operating lease liabilities – current and noncurrent portions		(560)		(560)
Other long-term liabilities		(475)		(475)
Total liabilities		(3,187)		(3,187)
Noncontrolling interest		(10,281)
Total stockholders' equity		(10,281)		(10,281)
Goodwill		35,747		35,747
Eleos [Member] | Customer relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets		8,800		8,800
Eleos [Member] | Noncompete agreements [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets		200		200
Eleos [Member] | Internally developed software [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets		3,500		3,500
Eleos [Member] | Trade Names
Business Acquisition [Line Items]
Finite-lived intangible assets		$ 3,400		$ 3,400
[1]	Includes $8.8 million in customer relationships, $0.2 million in noncompete agreements, $3.5 million in internally-developed software, and a $3.4 million trade name.

Acquisitions - Warehousing (Det

Acquisitions - Warehousing (Details) - USD ($) $ in Thousands		Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability	[1]	$ 21,200	$ 16,200
Warehousing Co [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability		$ 16,200	$ 16,200
[1]	The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets.

Restricted Investments, Held-_2

Restricted Investments, Held-to-Maturity (Details) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021USD ($)Securities	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)Securities	Jun. 30, 2020USD ($)	Dec. 31, 2020USD ($)Securities
Schedule of Investments [Line Items]
Cost or Amortized Cost	[1]	$ 8,589		$ 8,589		$ 9,001
Gross Unrealized Gains		0		0		2
Gross Unrealized Temporary Losses		(3)		(3)		(8)
Restricted investments, held-to-maturity 1	[1]	$ 8,586		$ 8,586		$ 8,995
Securities with unrealized losses for less than 12 months | Securities		14		14		16
Impairment losses		$ 0	$ 0	$ 0	$ 0
US corporate securities [Member]
Schedule of Investments [Line Items]
Cost or Amortized Cost		8,589		8,589		$ 9,001
Gross Unrealized Gains		0		0		2
Gross Unrealized Temporary Losses		(3)		(3)		(8)
Restricted investments, held-to-maturity 1		$ 8,586		$ 8,586		$ 8,995
Maximum [Member]
Schedule of Investments [Line Items]
Contractual maturities of fixed maturity securities				one year
Duration of securities in unrealized loss position				12 months
[1]	Refer to Note 4 for the differences between the carrying amounts and estimated fair values of the Company's restricted investments, held-to-maturity.

Embark Convertible Note (Detail

Embark Convertible Note (Details) - USD ($) $ in Thousands	Apr. 16, 2021	Jun. 30, 2021	[1]	Dec. 31, 2020
Schedule of Investments [Abstract]
Investment Owned, Face Amount	$ 25,000
Convertible Note Interest Rate	10.00%
Investment Owned, at Fair Value		$ 37,631		$ 0
[1]	The loan is carried at fair value and is included in "Other current assets" in the condensed consolidated balance sheets.

Assets Held For Sale (Details)

Assets Held For Sale (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Long Lived Assets Held-for-sale [Line Items]
Period Assets are Expected To Be Sold			12 months
Gain on disposal of assets held for sale			$ 25,592	$ 4,724
Equipment [Member]
Long Lived Assets Held-for-sale [Line Items]
Assets Held for Sale	$ 17,600		17,600		$ 29,800
Gain on disposal of assets held for sale	15,100	$ 1,700	25,600	4,700
Impairments	$ 0	$ 400	$ 0	$ 400

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets Summary of Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		$ 2,971,023		$ 2,971,023		$ 2,922,964
Adjustments relating to deferred tax assets				(3)
Acquisition	[1]			48,062
Goodwill impairments		$ 0	$ 0	$ 0	$ 0
[1]	The goodwill associated with the Eleos and UTXL acquisitions referenced in Note 3 was allocated to the non-reportable and logistics segments, respectively, and is net of purchase price accounting adjustments.

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets Intangible Asset Balances (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2021	Dec. 31, 2020
Definite-lived intangible assets 1
Gross carrying amount	[1]	$ 929,910	$ 894,597
Accumulated amortization		(169,585)	(145,852)
Definite-lived intangible assets, net		760,325	748,745
Indefinite-lived trade names:
Gross carrying amount		643,158	640,500
Intangible assets, net		$ 1,403,483	$ 1,389,245
Intangible Assets Other Than the 2017 Merger [Member]
Schedule of finite-lived intangible assets amortization expense [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		17 years 6 months
Intangible assets related to the 2017 Merger [Member] [Member]
Schedule of finite-lived intangible assets amortization expense [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		19 years 10 months 24 days
[1]	The major categories of the Company's definite-lived intangible assets include customer relationships, non-compete agreements, internally-developed software, trade names, and others.

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets Narrative (Details) $ in Millions	Jun. 30, 2021USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense, 2021	$ 24.4
Amortization expense, 2022	48.8
Amortization expense, 2023	48.2
Amortization expense, 2024	48.2
Amortization Expense, 2025	$ 48.1

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Income Tax Contingency [Line Items]
Effective tax rate	25.30%	25.00%	25.50%	26.00%
Deferred Tax Assets, Valuation Allowance	$ 0		$ 0
Decrease in Unrecognized Tax Benefits is Reasonably Possible	0.7		0.7
Accrued interest and penalties	$ 0.4		$ 0.4		$ 0.3
Year subject to examination			2015
State and Local Jurisdiction [Member] | Minimum [Member]
Income Tax Contingency [Line Items]
Year under income tax examination			2013
State and Local Jurisdiction [Member] | Maximum [Member]
Income Tax Contingency [Line Items]
Year under income tax examination			2019

Accounts Receivable Securitiz_3

Accounts Receivable Securitization (Details) - USD ($) $ in Thousands		Jun. 30, 2021	Apr. 23, 2021	Dec. 31, 2020	Jul. 11, 2018	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Servicing Liabilities at Fair Value [Line Items]
Program fees						$ 800	$ 700	$ 1,400	$ 2,100
2018 RSA [Member]
Servicing Liabilities at Fair Value [Line Items]
Effective date					Jul. 11, 2018
Final maturity date					Jul. 9, 2021
Receivables Sales Agreement, Borrowing Capacity					$ 325,000
Accordion Option Accounts Receivable Securitization	[1]				$ 175,000
Unused commitment fee rate					20 to 40 basis points
Program fees on outstanding balances	[2],[3]				one-month LIBOR + 80 to 100 basis points
Accounts receivable securitization – less current portion				$ 302,700
Accounts receivable securitization	[4]			(214,000)
Letters of Credit Outstanding, Amount				(67,281)
Availability under accounts receivable securitization facilities				21,419
Deferred loan costs				$ 100
Debt Instrument, Interest Rate During Period				1.00%
2021 RSA
Servicing Liabilities at Fair Value [Line Items]
Effective date			Apr. 23, 2021
Final maturity date			Apr. 23, 2024
Receivables Sales Agreement, Borrowing Capacity			$ 400,000
Accordion Option Accounts Receivable Securitization	[1]		$ 100,000
Unused commitment fee rate	[5]		20 to 40 basis points
Program fees on outstanding balances	[2]		one-month LIBOR + 82.5 basis points
Accounts receivable securitization – less current portion		$ 400,000				400,000		400,000
Accounts receivable securitization	[4]	(279,000)				(279,000)		(279,000)
Letters of Credit Outstanding, Amount		(65,281)				(65,281)		(65,281)
Availability under accounts receivable securitization facilities		55,719				55,719		55,719
Deferred loan costs		$ 600				$ 600		$ 600
Debt Instrument, Interest Rate During Period		0.90%
[1]	The accordion option increases the maximum borrowing capacity, subject to participation of the purchasers.
[2]	As identified within the 2021 RSA, the lender can trigger an amendment by identifying and deciding upon a replacement for LIBOR.
[3]	Only the rate for the 2018 RSA program fee is subject to the Company's consolidated total net leverage ratio.
[4]	As of June 30, 2021, outstanding borrowings are included in "Accounts receivable securitization – less current portion" in the condensed consolidated balance sheets and are offset by $0.6 million of deferred loan costs. As of December 31, 2020, outstanding borrowings are included in "Accounts receivable securitization – current portion" in the condensed consolidated balance sheets and are offset by $0.1 million of deferred loan costs . Interest accrued on the aggregate principal balance at a rate of 0.9% and 1.0% as of June 30, 2021 and December 31, 2020, respectively.
[5]	The 2021 RSA and 2018 RSA commitment fees rate are based on the percentage of the maximum borrowing capacity utilized.

Commitments (Details)

Commitments (Details) $ in Millions	Jun. 30, 2021USD ($)
Capital Addition Purchase Commitments Total Revenue Equipment [Member]
Long-term Purchase Commitment [Line Items]
Purchase Obligation, Future Minimum Payments, Remainder of Fiscal Year	$ 509.2
Purchase Obligation, Due in Second and Third Year	0
Purchase Obligation, Due in Fourth and Fifth Year	0
Purchase Obligation, Due after Fifth Year	0
Capital Addition Purchase Commitments of Tractors [Member]
Long-term Purchase Commitment [Line Items]
Purchase Obligation, Future Minimum Payments, Remainder of Fiscal Year	317.3
Capital Addition Purchase Commitments Non revenue equipment [Member]
Long-term Purchase Commitment [Line Items]
Purchase Obligation, Future Minimum Payments, Remainder of Fiscal Year	36.9
Purchase Obligation, Due in Second and Third Year	4.6
Purchase Obligation, Due in Fourth and Fifth Year	0.8
Purchase Obligation, Due after Fifth Year	0
Fuel Purchase Commitment [Member]
Long-term Purchase Commitment [Line Items]
Purchase Obligation, Future Minimum Payments, Remainder of Fiscal Year	14.5
Purchase Obligation, Due in Second and Third Year	0
Purchase Obligation, Due in Fourth and Fifth Year	0
Purchase Obligation, Due after Fifth Year	0
Transportation Resource Partners Capital Partners V [Member]
Long-term Purchase Commitment [Line Items]
Additional Amounts Committed To Invest	10
Amounts Committed To Invest	30
Remaining Investment Commitment	26.3
Embark
Long-term Purchase Commitment [Line Items]
Amounts Committed To Invest	25
Remaining Investment Commitment	$ 25

Legal Proceedings (Details)

Legal Proceedings (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Loss contingency accrual	$ 23.9
Accrual for Environmental Loss Contingencies, Gross	$ 0.5
Employee Compensation and Pay Practices Matters [Member] | CRST Expedited [Member]
Loss Contingencies [Line Items]
Loss contingency, allegations	The plaintiff alleges tortious interference with contract and unjust enrichment related to non-competition agreements entered into with certain of its drivers.
Loss contingency, name of plaintiffs	CRST Expedited, Inc.
Loss contingency, name of defendant	Swift Transportation Co. of Arizona LLC.
Lawsuit filing date	March 20, 2017
Loss contingency, domicile of litigation	United States District Court for the Northern District of Iowa
Loss contingency, opinion of counsel	In July 2019, a jury issued an adverse verdict in this lawsuit. The court issued a decision granting in part and denying in part certain motions related to the jury’s verdict. Both parties have appealed the court’s decision. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021.
Employee Compensation and Pay Practices Matters [Member] | California Wage, Meal, and Rest Class Action [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	In April 2019, the parties reached settlement of this matter. In January 2020, the court granted final approval of the settlement. Two objectors appealed the court’s decision granting final approval of the settlement. The likelihood that a loss has been incurred is probable and estimable, and the loss has accordingly been accrued as of June 30, 2021.
Employee Compensation and Pay Practices Matters [Member] | California Wage, Meal, and Rest Class Action [Member] | California Wage, Meal, and Rest Class Action 1 [Member]
Loss Contingencies [Line Items]
Loss contingency, name of plaintiffs	John Burnell 1	[1]
Loss contingency, name of defendant	Swift Transportation Co., Inc
Lawsuit filing date	March 22, 2010
Loss contingency, domicile of litigation	United States District Court for the Central District of California
Employee Compensation and Pay Practices Matters [Member] | California Wage, Meal, and Rest Class Action [Member] | California Wage, Meal, and Rest Class Action 2 [Member]
Loss Contingencies [Line Items]
Loss contingency, name of plaintiffs	James R. Rudsell 1	[1]
Loss contingency, name of defendant	Swift Transportation Co. of Arizona, LLC and Swift Transportation Company
Lawsuit filing date	April 5, 2012
Loss contingency, domicile of litigation	United States District Court for the Central District of California
Independent Contractor Matters [Member] | Ninth circuit owner operator misclassification class action 1 [Member]
Loss Contingencies [Line Items]
Loss contingency, allegations	The putative class alleges that Swift misclassified independent contractors as independent contractors, instead of employees, in violation of the Fair Labor Standards Act and various state laws. The lawsuit also raises certain related issues with respect to the lease agreements that certain independent contractors have entered into with Interstate Equipment Leasing, LLC. The putative class seeks unpaid wages, liquidated damages, interest, other costs, and attorneys' fees.
Loss contingency, name of plaintiffs	Joseph Sheer, Virginia Van Dusen, Jose Motolinia, Vickii Schwalm, Peter Wood 1	[1]
Loss contingency, name of defendant	Swift Transportation Co., Inc., Interstate Equipment Leasing, Inc., Jerry Moyes, and Chad Killebrew
Lawsuit filing date	December 22, 2009
Loss contingency, domicile of litigation	Unites States District Court of Arizona and Ninth Circuit Court of Appeals
Loss contingency, opinion of counsel	In January 2020, the court granted final approval of the settlement in this matter. In March 2020, the Company paid the settlement amount approved by the court. As of June 30, 2021, the Company has accrued for anticipated costs associated with finalizing this matter.
[1]	Individually and on behalf of all others similarly situated.

Contingencies and Legal Proce_3

Contingencies and Legal Proceedings Self Insurance (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)
Loss Contingencies [Line Items]
Self Insurance Retention	$ 10
Excess coverage layer	5
Excess of excess coverage layer	5
Cargo Insurance per truck or trailer	2
Cargo insurance per occurrence	10
Knight Transportation Company [Member]
Loss Contingencies [Line Items]
Insurance Aggregate Deductible Amount	2.5
Self Retention For Employee Medical Health	0.4
Knight Transportation Company [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Self Insurance Retention	1
Knight Transportation Company [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Self Insurance Retention	3
Swift Transportation Company [Member]
Loss Contingencies [Line Items]
Self Insurance Retention	10
Self Insurance Retention Workers Compensation Claims Per Occurrence	5
Self Retention For Employee Medical Health	0.5
Policy Period November 1, 2020 to October 31, 2021
Loss Contingencies [Line Items]
Self Insurance Aggregate Coverage	100
Policy Period November 1, 2019 to October 31, 2020 [Member]
Loss Contingencies [Line Items]
Self Insurance Aggregate Coverage	130
Policy Period, March 1, 2019 to March 1, 2020 [Member] | Knight Transportation Company [Member]
Loss Contingencies [Line Items]
Excess Personal Injury And Property Damage Liability Insurance	$ 2

Share Repurchase Plan (Details)

Share Repurchase Plan (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Nov. 24, 2020	May 30, 2019
Class of Stock [Line Items]
Company shares repurchased				$ 53,661	$ 34,630
Knight-Swift Share Repurchase Plan, May 31, 2019 [Member]
Class of Stock [Line Items]
Share repurchase plan, authorized amount, value								$ 250,000
Share repurchase, shares			0		1,139
Company shares repurchased			$ 0		$ 34,630
Share repurchase plan, remaining authorized amount, value							$ 54,100
Knight-Swift Share Repurchase Plan, November 24, 2020
Class of Stock [Line Items]
Share repurchase plan, authorized amount, value	[1]						$ 250,000
Share repurchase, shares	[1]	0		1,303
Company shares repurchased	[1]	$ 0		$ 53,661
Share repurchase plan, remaining authorized amount, value		$ 196,300		$ 196,300		$ 250,000
[1]	$196.3 million and $250.0 million remained available under the 2020 Knight-Swift Share Repurchase Plan as of June 30, 2021 and December 31, 2020, respectively.

Weighted Average Shares Outst_3

Weighted Average Shares Outstanding (Details) - shares shares in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Basic weighted average common shares outstanding		165,577	169,948	165,751	170,283
Dilutive effect of equity awards		1,008	676	999	675
Diluted weighted average common shares outstanding		166,585	170,624	166,750	170,958
Anti-dilutive shares excluded from diluted earnings per share	[1]	31	365	47	329
[1]	Shares were excluded from the dilutive-effect calculation because the outstanding awards' exercise prices were greater than the average market price of the Company's common stock for the periods presented.

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Receivable		$ 1,792		$ 1,792		$ 135
Payable		20		20		51
Freight Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift		0	$ 1,048	0	$ 7,864
Received by Knight-Swift		0	0	0	0
Facility and Equipment Leases [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift		0	27	0	32
Received by Knight-Swift		88	129	145	294
Other Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift		7	10	13	34
Received by Knight-Swift		9	19	18	31
Central Freight Lines, Inc. [Member]
Related Party Transaction [Line Items]
Receivable		0		0		133
Payable		0		0		0
Central Freight Lines, Inc. [Member] | Freight Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	1,020	0	7,836
Received by Knight-Swift	[1]	0	0	0	0
Central Freight Lines, Inc. [Member] | Facility and Equipment Leases [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	23	0	23
Received by Knight-Swift	[1]	0	93	0	185
Central Freight Lines, Inc. [Member] | Other Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	0	0	15
Received by Knight-Swift	[1]	0	0	0	0
SME Industries [Member] | Freight Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	28	0	28
Received by Knight-Swift	[1]	0	0	0	0
DPF Mobile [Member]
Related Party Transaction [Line Items]
Receivable		0		0		0
Payable		0		0		41
DPF Mobile [Member] | Other Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	0	0	0
Received by Knight-Swift	[1]	0	19	0	31
Other Affiliates [Member]
Related Party Transaction [Line Items]
Receivable		1,792		1,792		2
Payable		20		20		$ 10
Other Affiliates [Member] | Facility and Equipment Leases [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	0	4	0	9
Received by Knight-Swift	[1]	88	36	145	109
Other Affiliates [Member] | Other Services [Member]
Related Party Transaction [Line Items]
Provided by Knight-Swift	[1]	7	10	13	19
Received by Knight-Swift	[1]	$ 9	$ 0	$ 18	$ 0
[1]	Entities affiliated with former Board member Jerry Moyes include Central Freight Lines, SME Industries, Compensi Services, and DPF Mobile. "Other affiliates" includes entities that are associated with various board members and executives and require approval by the Board prior to completing transactions. Transactions with these entities generally include freight services, facility and equipment leases, equipment sales, and other services. • Freight Services Provided by Knight-Swift — The Company charges each of these companies for transportation services. • Freight Services Received by Knight-Swift — Transportation services received from Central Freight Lines represent less-than-truckload freight services rendered to haul parts and equipment to Company shop locations. • Other Services Provided by Knight-Swift — Other services provided by the Company to the identified related parties include equipment sales and miscellaneous services. • Other Services Received by Knight-Swift — Consulting fees, diesel particulate filter cleaning, sales of various parts and tractor accessories, and certain third-party payroll and employee benefits administration services from the identified related parties are included in other services received by the Company. During the quarter ended September 30, 2020, the ownership percentage of Jerry Moyes and related affiliates fell below the threshold requiring related party disclosure. The amounts included in this Note 13 pertain to transactions that occurred prior to the date that the ownership percentage changed.

Information by Segment and Ge_3

Information by Segment and Geography - Segment Financial Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)Segment	Jun. 30, 2020USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			3
Number of Operating Segments | Segment			22
Total revenue	$ 1,315,701	$ 1,060,698	$ 2,538,715	$ 2,185,496
Operating income (loss)	191,115	102,167	353,374	204,286
Depreciation and amortization of property and equipment	123,606	114,601	243,521	224,822
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	1,267,973	1,032,293	2,456,873	2,125,283
Operating income (loss)	188,625	106,351	358,142	214,667
Depreciation and amortization of property and equipment	109,435	101,368	$ 215,346	198,611
Operating Segments [Member] | Trucking [Member]
Segment Reporting Information [Line Items]
Description of products and services			The Trucking reportable segment is comprised of nine trucking operating segments that provide similar transportation services to our customers utilizing similar transportation equipment over both irregular (one-way movement) and/or dedicated routes. The Trucking reportable segment consists of irregular route and dedicated, refrigerated, expedited, flatbed, and cross-border operations.
Total revenue	985,858	879,369	$ 1,948,805	1,798,430
Operating income (loss)	168,457	107,788	326,940	215,122
Depreciation and amortization of property and equipment	105,206	97,555	$ 207,091	191,103
Operating Segments [Member] | Logistics [Member]
Segment Reporting Information [Line Items]
Description of products and services			The Logistics reportable segment is comprised of six logistics operating segments that provide similar transportation services to our customers and primarily consist of brokerage and other freight management services utilizing third-party transportation providers and their equipment.
Total revenue	166,737	70,104	$ 285,624	149,302
Operating income (loss)	14,356	3,038	21,933	6,757
Depreciation and amortization of property and equipment	289	207	$ 497	414
Operating Segments [Member] | Intermodal [Member]
Segment Reporting Information [Line Items]
Description of products and services			The Intermodal reportable segment is comprised of two intermodal operating segments that provide similar transportation services to our customers. These transportation services include arranging the movement of customers' freight through third-party intermodal rail services on the Company’s trailing equipment (trailers on flat cars and rail containers), as well as drayage services to transport loads between the railheads and customer locations.
Total revenue	115,378	82,820	$ 222,444	177,551
Operating income (loss)	5,812	(4,475)	9,269	(7,212)
Depreciation and amortization of property and equipment	3,940	3,606	$ 7,758	7,094
Non-reportable segments [Member]
Segment Reporting Information [Line Items]
Description of all other segments			The non-reportable segments include five operating segments that consist of support services provided to the Company's customers and independent contractors (including repair and maintenance shop services, equipment leasing, warranty services, and insurance), trailer parts manufacturing, warehousing, and certain driving academy activities, as well as certain corporate expenses (such as legal settlements and accruals, certain impairments, and amortization of intangibles related to the 2017 Merger and various acquisitions).
Total revenue	66,795	45,289	$ 117,464	91,531
Operating income (loss)	2,490	(4,184)	(4,768)	(10,381)
Depreciation and amortization of property and equipment	14,171	13,233	28,175	26,211
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenue	$ (19,067)	$ (16,884)	$ (35,622)	$ (31,318)

Information by Segment and Ge_4

Information by Segment and Geography - Narrative (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Segment Reporting [Abstract]
Percentages Of Foreign Operations Consolidated Revenue	5.00%	5.00%	5.00%	5.00%
Long lived assets of foreign operations	5.00%		5.00%		5.00%

Fair Value Measurement - Estima

Fair Value Measurement - Estimated Fair Values (Details) - USD ($) $ in Thousands		Jun. 30, 2021		Dec. 31, 2020
Financial Assets:
Restricted investments, held-to-maturity, amortized cost	[1]	$ 8,589		$ 9,001
Restricted investments, held-to-maturity 1	[1]	8,586		8,995
Equity method investments 2	[2]	81,237		77,562
Equity method investments (Estimated Fair Value)	[2]	81,237		77,562
Investments in equity securities	[3]	19,707		18,675
Convertible note 4		37,631	[4]	0
Financial Liabilities:
Accounts receivable securitization		278,372		0
Revolving line of credit		55,000		210,000
Business Combination, Contingent Consideration, Liability	[5]	21,200		16,200
2017 Term Loan
Financial Liabilities:
Term loan Carrying Value	[6]	299,219		298,907
Term loan, Fair Value	[6]	300,000		300,000
Deferred loan costs		800		1,100
2018 RSA [Member]
Financial Liabilities:
Accounts receivable securitization		0		213,918	[7]
RSA, Fair Value Disclosure		0		214,000	[7]
Deferred loan costs				100
2021 RSA
Financial Liabilities:
Accounts receivable securitization		278,372	[8]	0
RSA, Fair Value Disclosure		279,000	[8]	$ 0
Deferred loan costs		$ 600
[1]	Refer to Note 4 for the differences between the carrying amounts and estimated fair values of the Company's restricted investments, held-to-maturity.
[2]	Net equity method investment balances included in "Other long-term assets" in the condensed consolidated balance sheets.
[3]	The investments are carried at fair value and are included in "Other long-term assets" on the condensed consolidated balance sheets.
[4]	The loan is carried at fair value and is included in "Other current assets" in the condensed consolidated balance sheets.
[5]	The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets.
[6]	The carrying amount of the 2017 Term Loan is included in "Finance lease liabilities and long-term debt – less current portion," on the condensed consolidated balance sheets and is net of $0.8 million and $1.1 million in deferred loan costs as of June 30, 2021 and December 31, 2020, respectively.
[7]	The carrying amount of the 2018 RSA is included in " Accounts receivable securitization – current portion ," on the condensed consolidated balance sheets and is net of $0.1 million in deferred loan costs as of December 31, 2020 .
[8]	The carrying amount of the 2021 RSA is included in " Accounts receivable securitization – less current portion ," on the condensed consolidated balance sheets and is net of $0.6 million in deferred loan costs as of June 30, 2021 .

Fair Value Measurement - Recurr

Fair Value Measurement - Recurring and Nonrecurring Measurements (Details) - USD ($) $ in Thousands		3 Months Ended					6 Months Ended			12 Months Ended
		Jun. 30, 2021		Dec. 31, 2020		Jun. 30, 2020	Jun. 30, 2021		Jun. 30, 2020	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible note 4		$ 37,631	[1]	$ 0			$ 37,631	[1]		$ 0
Business Combination, Contingent Consideration, Liability	[2]	21,200		16,200			21,200			16,200
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible note 4	[3]	37,631					37,631
Gain (Loss) on Investments	[3]						12,631
Assets, Fair Value Disclosure		19,707	[4]	18,675	[5]		19,707	[4]		18,675	[5]
Fair Value, Option, Changes in Fair Value, Gain (Loss)							8,126	[4]		3,553	[5]
Debt and Equity Securities, Gain (Loss)		(1,500)					8,900
Debt and Equity Securities, Unrealized Gain (Loss)		(2,300)				$ 7,600	4,600		$ 2,500
Debt and Equity Securities, Realized Gain (Loss)		800					4,300
Business Combination, Contingent Consideration, Liability		21,200	[6]	16,200	[7]		21,200	[6]		16,200	[7]
Contingent Consideration Gain (Loss)		0		6,700		0	0	[6]	0	(6,730)	[7]
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible note 4	[3]	0					0
Assets, Fair Value Disclosure		19,707	[4]	18,675	[5]		19,707	[4]		18,675	[5]
Business Combination, Contingent Consideration, Liability		0	[6]	0	[7]		0	[6]		0	[7]
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible note 4	[3]	0					0
Assets, Fair Value Disclosure		0	[4]	0	[5]		0	[4]		0	[5]
Business Combination, Contingent Consideration, Liability		0	[6]	0	[7]		0	[6]		0	[7]
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible note 4	[3]	37,631					37,631
Assets, Fair Value Disclosure		0	[4]	0	[5]		0	[4]		0	[5]
Business Combination, Contingent Consideration, Liability		21,200	[6]	16,200	[7]		21,200	[6]		16,200	[7]
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		0					0
Financial and Nonfinancial Liabilities, Fair Value Disclosure		0		$ 0			0			0
Equipment [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[8]	5,851					5,851
Total Losses, Equipment						$ (400)			$ (1,300)	$ (5,335)	[8]
Equipment [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[8]	0					0
Equipment [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[8]	5,851					5,851
Equipment [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	[8]	$ 0					$ 0
[1]	The loan is carried at fair value and is included in "Other current assets" in the condensed consolidated balance sheets.
[2]	The carrying amount of the contingent consideration associated with acquisitions is included in both the "Accrued liabilities" and "Other long-term liabilities" line items on the condensed consolidated balance sheets.
[3]	The Company recognized $12.6 million of unrealized gains on the convertible note for the quarter and year-to-date periods ended June 30, 2021, which is included within "Other income, net" within the condensed consolidated statement of comprehensive income. The fair value of the note was determined using a discounted cash flow analysis based on the probability of exit event options and exit event dates.
[4]	Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2021, the Company recognized $1.5 million in net losses on these investments in equity securities, consisting of $2.3 million in unrealized losses and $0.8 million in realized gains.
[5]	3 Fair value activity from the investments in equity securities is recorded in "Other income, net" within the condensed consolidated statement of comprehensive income. • During the quarter ended June 30, 2020, the Company recognized $7.6 million in unrealized gains on these investments in equity securities. • During the year-to-date period ended June 30, 2020, the Company recognized $2.5 million in unrealized gains on these investments in equity securities.
[6]	The Company did not recognize any gains (losses) during the quarter or year-to-date periods ended June 30, 2021 related to the revaluation of these liabilities. Refer to Note 3 for information regarding the components of these liabilities.
[7]	During the fourth quarter of 2020, the Company increased the estimated fair value of the remaining contingent consideration representing the final two annual payments, resulting in a $6.7 million fair value adjustment of the deferred earnout, which was recorded in “Miscellaneous operating expenses” in the consolidated statement of comprehensive income. The Company did not recognize any losses during the quarter and year-to-date periods ended June 30, 2020
[8]	Reflects the non-cash impairment of certain alternative fuel technology (within the non-reportable segments) and certain revenue equipment held for sale (within the Trucking segment). The Company recognized $0.4 million and $1.3 million of impairments during the quarter and year-to-date periods ended June 30, 2020.