$KNX
Knight-Swift Transportation Holdings Inc. Stock $knx

$knx Overview Financials Valuation SEC Filings Company Website

2020 Form 10-K Financial Statement

#000149269121000016 Filed on February 25, 2021

Income Statement

Concept	2020	2019 Q4	2018 Q4
Revenue	$4.674B	$1.197B	$1.395B
YoY Change	-3.51%	-14.19%	2.59%
Cost Of Revenue	$1.628B	$473.6M	$560.3M
YoY Change	-16.13%	-15.47%	-3.28%
Gross Profit	$3.046B	$723.2M	$834.3M
YoY Change	4.92%	-13.32%	6.93%
Gross Profit Margin	65.16%	60.43%	59.82%
Selling, General & Admin	$1.782B	$433.1M	$473.4M
YoY Change	-1.57%	-8.51%	-3.74%
% of Gross Profit	58.52%	59.89%	56.74%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$506.7M	$120.1M	$110.9M
YoY Change	9.44%	8.3%	8.83%
% of Gross Profit	16.64%	16.61%	13.29%
Operating Expenses	$12.30M	$617.3M	$624.8M
YoY Change	-99.72%	-1.2%	-1.79%
Operating Profit	$564.4M	$67.58M	$151.9M
YoY Change	32.05%	-55.53%	-66.07%
Interest Expense	$17.31M	-$6.300M	-$7.700M
YoY Change	-41.19%	-18.18%	26.23%
% of Operating Profit	3.07%	-9.32%	-5.07%
Other Income/Expense, Net	-$4.127M	-$400.0K	$3.500M
YoY Change	-69.34%	-111.43%	400.0%
Pretax Income	$560.3M	$92.90M	$202.5M
YoY Change	35.35%	-54.12%	46.32%
Income Tax	$149.7M	$25.30M	$50.60M
% Of Pretax Income	26.71%	27.23%	24.99%
Net Earnings	$410.0M	$67.44M	$151.7M
YoY Change	32.6%	-55.54%	-66.11%
Net Earnings / Revenue	8.77%	5.64%	10.88%
Basic Earnings Per Share	$2.42	$0.40	$0.87
Diluted Earnings Per Share	$2.40	$0.39	$0.86
COMMON SHARES
Basic Shares Outstanding	169.7M shares	170.6M shares	174.5M shares
Diluted Shares Outstanding	170.5M shares

Balance Sheet

Concept	2020	2019 Q4	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$156.7M	$159.7M	$82.50M
YoY Change	-1.88%	93.58%	7.7%
Cash & Equivalents	$156.7M	$159.7M	$82.49M
Short-Term Investments
Other Short-Term Assets	$185.2M	$27.85M	$29.71M
YoY Change	-4.93%	-6.25%	-21.02%
Inventory
Prepaid Expenses		$62.16M	$67.01M
Receivables	$554.2M	$518.5M	$601.2M
Other Receivables	$27.20M	$17.10M	$7.000M
Total Short-Term Assets	$923.4M	$890.0M	$907.2M
YoY Change	3.75%	-1.9%	-1.73%
LONG-TERM ASSETS
Property, Plant & Equipment	$3.106B	$2.851B	$2.613B
YoY Change	2.84%	9.1%	9.59%
Goodwill		$2.919B	$2.919B
YoY Change		-0.01%	1.08%
Intangibles		$1.379B	$1.421B
YoY Change		-2.92%	-1.39%
Long-Term Investments
YoY Change
Other Assets	$126.5M	$73.11M	$51.72M
YoY Change	73.05%	41.35%	9.48%
Total Long-Term Assets	$7.545B	$7.392B	$7.005B
YoY Change	2.07%	5.53%	3.62%
TOTAL ASSETS
Total Short-Term Assets	$923.4M	$890.0M	$907.2M
Total Long-Term Assets	$7.545B	$7.392B	$7.005B
Total Assets	$8.468B	$8.282B	$7.912B
YoY Change	2.25%	4.67%	2.97%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$101.0M	$99.19M	$117.9M
YoY Change	1.81%	-15.85%	-1.66%
Accrued Expenses	$297.3M	$175.2M	$151.5M
YoY Change	-18.64%	15.66%	-18.71%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$52.60M	$364.8M	$421.0K
YoY Change	-86.07%	86556.77%	1303.33%
Total Short-Term Liabilities	$839.7M	$993.0M	$614.6M
YoY Change	-15.44%	61.58%	0.82%
LONG-TERM LIABILITIES
Long-Term Debt	$647.2M	$0.00	$364.6M
YoY Change	19.61%	-100.0%	-0.05%
Other Long-Term Liabilities	$293.2M	$14.46M	$23.29M
YoY Change	-4.65%	-37.95%	-11.76%
Total Long-Term Liabilities	$940.4M	$14.46M	$387.9M
YoY Change	10.82%	-96.27%	-0.84%
TOTAL LIABILITIES
Total Short-Term Liabilities	$839.7M	$993.0M	$614.6M
Total Long-Term Liabilities	$940.4M	$14.46M	$387.9M
Total Liabilities	$2.598B	$2.613B	$2.449B
YoY Change	-0.66%	6.71%	0.25%
SHAREHOLDERS EQUITY
Retained Earnings		$1.395B	$1.217B
YoY Change		14.68%	19.68%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$5.870B	$5.666B	$5.461B
YoY Change
Total Liabilities & Shareholders Equity	$8.468B	$8.282B	$7.912B
YoY Change	2.25%	4.67%	2.97%

Cashflow Statement

Concept	2020	2019 Q4	2018 Q4
OPERATING ACTIVITIES
Net Income	$410.0M	$67.44M	$151.7M
YoY Change	32.6%	-55.54%	-66.11%
Depreciation, Depletion And Amortization	$506.7M	$120.1M	$110.9M
YoY Change	9.44%	8.3%	8.83%
Cash From Operating Activities	$919.6M	$227.2M	$301.4M
YoY Change	9.53%	-24.62%	61.78%
INVESTING ACTIVITIES
Capital Expenditures	-$521.1M	-$194.0M	-$253.3M
YoY Change	-37.22%	-23.41%	-14.22%
Acquisitions	$46.81M
YoY Change	2383.34%
Other Investing Activities	$42.32M	$78.80M	$73.50M
YoY Change	887.86%	7.21%	34.37%
Cash From Investing Activities	-$480.7M	-$115.3M	-$179.8M
YoY Change	-17.64%	-35.87%	-25.27%
FINANCING ACTIVITIES
Cash Dividend Paid	$54.62M
YoY Change	31.85%
Common Stock Issuance & Retirement, Net	$179.6M
YoY Change	106.68%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$443.9M	-45.40M	-131.9M
YoY Change	140.41%	-65.58%	-2588.68%
NET CHANGE
Cash From Operating Activities	$919.6M	227.2M	301.4M
Cash From Investing Activities	-$480.7M	-115.3M	-179.8M
Cash From Financing Activities	-$443.9M	-45.40M	-131.9M
Net Change In Cash	-$4.951M	66.50M	-10.30M
YoY Change	-106.95%	-745.63%	-78.98%
FREE CASH FLOW
Cash From Operating Activities	$919.6M	$227.2M	$301.4M
Capital Expenditures	-$521.1M	-$194.0M	-$253.3M
Free Cash Flow	$1.441B	$421.2M	$554.7M
YoY Change	-13.71%	-24.07%	15.18%

Facts In Submission

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CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001492691
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-35007
CY2020	dei	Entity Registrant Name EntityRegistrantName	Knight-Swift Transportation Holdings Inc.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	20-5589597
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	20002 North 19th Avenue
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Phoenix
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	AZ
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	85027
CY2020	dei	City Area Code CityAreaCode	602
CY2020	dei	Local Phone Number LocalPhoneNumber	269-2000
CY2020	dei	Security12b Title Security12bTitle	Common Stock $0.01 Par Value
CY2020	dei	Trading Symbol TradingSymbol	KNX
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
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CY2018	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	61626000	USD
CY2020	us-gaap	Costs And Expenses CostsAndExpenses	4109425000	USD
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	4416512000	USD
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	4775023000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	564438000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	427438000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	569043000	USD
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	1928000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	3834000	USD
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	3200000	USD
CY2020	us-gaap	Interest Expense InterestExpense	17309000	USD
CY2019	us-gaap	Interest Expense InterestExpense	29433000	USD
CY2018	us-gaap	Interest Expense InterestExpense	30170000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-17005000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	11254000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	12137000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	9965000	USD
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-4127000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-13462000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	560311000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	413976000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	552038000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	149676000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	103798000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	131389000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	410635000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	310178000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	420649000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	633000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	972000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	1385000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	410002000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	309206000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	419264000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.42
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.80
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.37
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.40
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.80
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.36
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.32
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	169711000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	171541000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	177018000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	170549000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172142000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	177999000	shares
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5240370000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	10950000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	774000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1823000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	179318000	USD
CY2018	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	2550000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Stock Options Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	11488000	USD
CY2018	us-gaap	Dividends Dividends	42642000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	419264000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	2253000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	1385000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Other AdjustmentsToAdditionalPaidInCapitalOther	-1873000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5462719000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	654000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Stock Options Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	19639000	USD
CY2020	us-gaap	Dividends Dividends	54661000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	10478000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	531000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2298000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	86892000	USD
CY2019	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	2330000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Stock Options Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	13375000	USD
CY2019	us-gaap	Dividends Dividends	41400000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	309206000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	972000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5668303000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	10013000	USD
CY2020	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	515000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2220000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	179585000	USD
CY2020	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	4510000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	410002000	USD
CY2020	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	529000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	633000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5872040000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	410635000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	310178000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	420649000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	506670000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	462958000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	430089000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	9706000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	32935000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	36236000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	5335000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	3486000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	2798000	USD
CY2020	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-46214000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-30731000	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-62469000	USD
CY2020	us-gaap	Amortization Of Leased Asset AmortizationOfLeasedAsset	80891000	USD
CY2019	us-gaap	Amortization Of Leased Asset AmortizationOfLeasedAsset	120769000	USD
CY2018	us-gaap	Amortization Of Leased Asset AmortizationOfLeasedAsset	0	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-43682000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-24156000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-4617000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	75521000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-70106000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	9375000	USD
CY2020	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-14123000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	10069000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-48171000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	7500000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-13180000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-18033000	USD
CY2020	knx	Increase Decreasein Accrued Liabilitiesand Other Liabilities IncreaseDecreaseinAccruedLiabilitiesandOtherLiabilities	-31210000	USD
CY2019	knx	Increase Decreasein Accrued Liabilitiesand Other Liabilities IncreaseDecreaseinAccruedLiabilitiesandOtherLiabilities	-919000	USD
CY2018	knx	Increase Decreasein Accrued Liabilitiesand Other Liabilities IncreaseDecreaseinAccruedLiabilitiesandOtherLiabilities	-14367000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-83675000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-121737000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	0	USD
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	4707000	USD
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-3950000	USD
CY2018	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-8805000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	919645000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	839594000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	881977000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Held To Maturity Securities ProceedsFromSaleAndMaturityOfHeldToMaturitySecurities	13675000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Held To Maturity Securities ProceedsFromSaleAndMaturityOfHeldToMaturitySecurities	22695000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Held To Maturity Securities ProceedsFromSaleAndMaturityOfHeldToMaturitySecurities	26970000	USD
CY2020	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	16936000	USD
CY2019	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	14302000	USD
CY2018	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	22156000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	133230000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	260140000	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	225821000	USD
CY2020	us-gaap	Payments To Acquire Machinery And Equipment PaymentsToAcquireMachineryAndEquipment	521067000	USD
CY2019	us-gaap	Payments To Acquire Machinery And Equipment PaymentsToAcquireMachineryAndEquipment	829977000	USD
CY2018	us-gaap	Payments To Acquire Machinery And Equipment PaymentsToAcquireMachineryAndEquipment	755997000	USD
CY2020	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	483000	USD
CY2019	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	16093000	USD
CY2018	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	30322000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	46811000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1885000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	101693000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	42320000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4284000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-10085000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-480712000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-583706000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-647292000	USD
CY2020	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	148910000	USD
CY2019	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	115642000	USD
CY2018	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	46630000	USD
CY2020	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	-69000000	USD
CY2019	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	84000000	USD
CY2018	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	70000000	USD
CY2020	us-gaap	Proceeds From Accounts Receivable Securitization ProceedsFromAccountsReceivableSecuritization	61000000	USD
CY2019	us-gaap	Proceeds From Accounts Receivable Securitization ProceedsFromAccountsReceivableSecuritization	150000000	USD
CY2018	us-gaap	Proceeds From Accounts Receivable Securitization ProceedsFromAccountsReceivableSecuritization	70000000	USD
CY2020	us-gaap	Repayments Of Accounts Receivable Securitization RepaymentsOfAccountsReceivableSecuritization	52000000	USD
CY2019	us-gaap	Repayments Of Accounts Receivable Securitization RepaymentsOfAccountsReceivableSecuritization	185000000	USD
CY2018	us-gaap	Repayments Of Accounts Receivable Securitization RepaymentsOfAccountsReceivableSecuritization	135000000	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	12748000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	13307000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	13547000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	179585000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	86892000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	179318000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	54620000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	41425000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	42770000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-13517000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2984000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-5271000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-443884000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-184636000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-255442000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-4951000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	71252000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-20757000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	202228000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	130976000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	151733000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	197277000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	202228000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	130976000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	17396000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	28916000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	28723000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	80006000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	78658000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	16106000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	651000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	6748000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	11931000	USD
CY2020	knx	Equipment Sales Receivables EquipmentSalesReceivables	223000	USD
CY2019	knx	Equipment Sales Receivables EquipmentSalesReceivables	1333000	USD
CY2018	knx	Equipment Sales Receivables EquipmentSalesReceivables	5565000	USD
CY2020	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	16200000	USD
CY2019	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	0	USD
CY2018	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	12406000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	9803000	USD
CY2018	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	137097000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2018	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	156699000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	159722000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	82486000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	39328000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	41331000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	46888000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	1250000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	1175000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	1602000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	197277000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	202228000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	130976000	USD
CY2020Q4	knx	Numberof Tractors In Fleet NumberofTractorsInFleet	18448	Vehicle
CY2020Q4	knx	Number Of Tractors Driven By Company Drivers NumberOfTractorsDrivenByCompanyDrivers	16379	Vehicle
CY2020Q4	knx	Number Of Owner Operator Tractors NumberOfOwnerOperatorTractors	2069	Vehicle
CY2020Q4	knx	Number Of Trailers In Fleet NumberOfTrailersInFleet	57722	Vehicle
CY2020Q4	knx	Number Of Intermodal Tractors NumberOfIntermodalTractors	577	Vehicle
CY2020Q4	knx	Number Of Intermodal Containers NumberOfIntermodalContainers	10604	Vehicle
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	Segment
CY2020	us-gaap	Operating Expenses OperatingExpenses	12300000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:3pt;text-align:justify"><span style="color:#00467e;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates —</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%"> </span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of the consolidated financial statements, in accordance with GAAP, requires management to make estimates and assumptions about future events that affect the amounts reported in the Company's consolidated financial statements and accompanying notes. On an ongoing basis, management evaluates and periodically adjusts its estimates and assumptions, based on historical experience, the impact of the current economic environment, and other key factors. Volatile energy markets, as well as changes in consumer spending have increased the inherent uncertainty in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Significant items subject to such estimates and assumptions include: </span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">carrying amount of property and equipment; </span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">carrying amount of goodwill and intangible assets;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">leases;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">estimates of claims accruals;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">contingent obligations;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">calculation of stock-based compensation;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">valuation allowance for deferred income tax assets;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">valuation allowances for receivables;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">valuation allowances for inventories; and</span></div><div style="margin-bottom:12pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">valuation of financial instruments.</span></div>
CY2020	knx	Percentage Of Income Tax Positions Likely To Be Realized PercentageOfIncomeTaxPositionsLikelyToBeRealized	0.50
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	9001000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	2000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	8000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	8995000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	8912000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	4000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	1000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	8915000	USD
CY2020	knx	Short Term Investment Contractual Maturity ShortTermInvestmentContractualMaturity	P1Y
CY2020Q4	us-gaap	Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions	16	Securities
CY2019Q4	us-gaap	Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions	7	Securities
CY2020	knx	Swft Durationof Securitiesin Unrealized Loss Position SWFT_DurationofSecuritiesinUnrealizedLossPosition	P12M
CY2019	us-gaap	Other Than Temporary Impairment Losses Investments Heldtomaturity Securities OtherThanTemporaryImpairmentLossesInvestmentsHeldtomaturitySecurities	0	USD
CY2018	us-gaap	Other Than Temporary Impairment Losses Investments Heldtomaturity Securities OtherThanTemporaryImpairmentLossesInvestmentsHeldtomaturitySecurities	0	USD
CY2020	us-gaap	Other Than Temporary Impairment Losses Investments Heldtomaturity Securities OtherThanTemporaryImpairmentLossesInvestmentsHeldtomaturitySecurities	0	USD
CY2020Q4	us-gaap	Notes And Loans Receivable Net Current NotesAndLoansReceivableNetCurrent	2846000	USD
CY2020Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	77562000	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	30878000	USD
CY2020Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	600572000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	536725000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	22093000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	18178000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	578479000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	518547000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	10325000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	15331000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	602000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	503000	USD
CY2020Q4	us-gaap	Accounts And Notes Receivable Net AccountsAndNotesReceivableNet	9723000	USD
CY2019Q4	us-gaap	Accounts And Notes Receivable Net AccountsAndNotesReceivableNet	14828000	USD
CY2019Q4	us-gaap	Notes And Loans Receivable Net Current NotesAndLoansReceivableNetCurrent	4163000	USD
CY2020Q4	us-gaap	Notes And Loans Receivable Net Noncurrent NotesAndLoansReceivableNetNoncurrent	6877000	USD
CY2019Q4	us-gaap	Notes And Loans Receivable Net Noncurrent NotesAndLoansReceivableNetNoncurrent	10665000	USD
CY2020	knx	Period Assetsare Expected To Be Sold PeriodAssetsareExpectedToBeSold	P12M
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	2918992000	USD
CY2018Q4	us-gaap	Goodwill Gross GoodwillGross	2919176000	USD
CY2017Q4	us-gaap	Goodwill Gross GoodwillGross	2887867000	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-11000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-232000	USD
CY2018	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-17000	USD
CY2020Q4	us-gaap	Goodwill Gross GoodwillGross	2922964000	USD
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	2918992000	USD
CY2018Q4	us-gaap	Goodwill Gross GoodwillGross	2919176000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	2922964000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	2918992000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	894597000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	839516000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	145852000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	99957000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	748745000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	739559000	USD
CY2020Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	640500000	USD
CY2019Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	639900000	USD
CY2019Q4	knx	Accrued Payrolland Purchased Transportation AccruedPayrollandPurchasedTransportation	110065000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1389245000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1379459000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	45895000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	42876000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	42584000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	45900000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	45800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	45200000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	45200000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	45100000	USD
CY2020Q4	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	114835000	USD
CY2019Q4	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	70534000	USD
CY2020Q4	knx	Accrued Purchased Transportation AccruedPurchasedTransportation	46053000	USD
CY2019Q4	knx	Accrued Purchased Transportation AccruedPurchasedTransportation	39531000	USD
CY2020Q4	knx	Accrued Payrolland Purchased Transportation AccruedPayrollandPurchasedTransportation	160888000	USD
CY2020	knx	Defined Contribution Plan Eligible Agefor Employee DefinedContributionPlanEligibleAgeforEmployee	P18Y
CY2020	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.030
CY2020	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Amount DefinedContributionPlanMaximumAnnualContributionsPerEmployeeAmount	2000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	13600000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	8800000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	8700000	USD
CY2020Q4	us-gaap	Postemployment Benefits Liability Current And Noncurrent PostemploymentBenefitsLiabilityCurrentAndNoncurrent	12800000	USD
CY2019Q4	us-gaap	Postemployment Benefits Liability Current And Noncurrent PostemploymentBenefitsLiabilityCurrentAndNoncurrent	9100000	USD
CY2020Q4	us-gaap	Accrued Professional Fees Current And Noncurrent AccruedProfessionalFeesCurrentAndNoncurrent	20206000	USD
CY2019Q4	us-gaap	Accrued Professional Fees Current And Noncurrent AccruedProfessionalFeesCurrentAndNoncurrent	121312000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	68688000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	53910000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	88894000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	175222000	USD
CY2020	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Claims accruals were comprised of the following: </span></div><div style="margin-bottom:6pt;margin-top:6pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.707%"><tr><td style="width:1.0%"/><td style="width:70.894%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.536%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.533%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.537%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="border-left:1pt solid #00467e;border-top:1pt solid #00467e;padding:0 1pt"/><td colspan="9" style="border-right:1pt solid #00467e;border-top:1pt solid #00467e;padding:2px 1pt;text-align:center;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7pt;font-weight:700;line-height:100%">December 31,</span></td></tr><tr><td colspan="3" style="border-left:1pt solid #00467e;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;border-right:1pt solid #00467e;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7pt;font-weight:700;line-height:100%">2019</span></td></tr><tr><td colspan="3" style="border-left:1pt solid #00467e;padding:0 1pt"/><td colspan="9" style="border-right:1pt solid #00467e;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7pt;font-weight:700;line-height:100%">(In thousands)</span></td></tr><tr><td colspan="3" style="background-color:#e0e0e0;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Auto reserves</span></td><td style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#e0e0e0;padding:2px 0;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">231,875 </span></td><td style="background-color:#e0e0e0;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#e0e0e0;padding:0 1pt"/><td style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#e0e0e0;padding:2px 0;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">224,541 </span></td><td style="background-color:#e0e0e0;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Workers’ compensation reserves</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">94,609 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">108,035 </span></td><td style="background-color:#ffffff;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#e0e0e0;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Independent contractor claims reserves</span></td><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">7,152 </span></td><td style="background-color:#e0e0e0;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#e0e0e0;padding:0 1pt"/><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">8,044 </span></td><td style="background-color:#e0e0e0;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Cargo damage reserves</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">2,494 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">2,818 </span></td><td style="background-color:#ffffff;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#e0e0e0;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Employee medical reserves</span></td><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">13,612 </span></td><td style="background-color:#e0e0e0;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#e0e0e0;padding:0 1pt"/><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">4,279 </span></td><td style="background-color:#e0e0e0;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="display:none"/><td colspan="3" style="display:none"/><td colspan="3" style="display:none"/><td colspan="3" style="display:none"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-left:1pt solid #00467e;padding:2px 1pt 2px 12.25pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Claims accruals</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">349,742 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">347,717 </span></td><td style="background-color:#ffffff;border-right:1pt solid #00467e;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#e0e0e0;border-left:1pt solid #00467e;padding:2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Less: current portion of claims accruals</span></td><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(174,928)</span></td><td style="background-color:#e0e0e0;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#e0e0e0;padding:0 1pt"/><td colspan="2" style="background-color:#e0e0e0;padding:2px 0 2px 1pt;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">(150,805)</span></td><td style="background-color:#e0e0e0;border-right:1pt solid #00467e;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-left:1pt solid #00467e;padding:2px 1pt 2px 12.25pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Claims accruals, less current portion</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">174,814 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:middle"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:100%">196,912 </span></td><td style="background-color:#ffffff;border-right:1pt solid #00467e;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:middle"/></tr><tr style="height:3pt"><td colspan="3" style="border-bottom:1pt solid #00467e;border-left:1pt solid #00467e;padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #00467e;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #00467e;padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #00467e;border-right:1pt solid #00467e;border-top:3pt double #000000;padding:0 1pt"/></tr></table></div>
CY2020Q4	us-gaap	Accrued Insurance Current And Noncurrent AccruedInsuranceCurrentAndNoncurrent	349742000	USD
CY2019Q4	us-gaap	Accrued Insurance Current And Noncurrent AccruedInsuranceCurrentAndNoncurrent	347717000	USD
CY2020Q4	us-gaap	Accrued Insurance Current AccruedInsuranceCurrent	174928000	USD
CY2019Q4	us-gaap	Accrued Insurance Current AccruedInsuranceCurrent	150805000	USD
CY2020Q4	us-gaap	Accrued Insurance Noncurrent AccruedInsuranceNoncurrent	174814000	USD
CY2019Q4	us-gaap	Accrued Insurance Noncurrent AccruedInsuranceNoncurrent	196912000	USD
CY2019	knx	Excesscoveragelayer Excesscoveragelayer	5000000.0	USD
CY2019	knx	Excessofexcesscoveragelayer Excessofexcesscoveragelayer	5000000.0	USD
CY2020Q4	knx	Self Insurance Retention SelfInsuranceRetention	10000000.0	USD
CY2020	knx	Cargo Insurancepertruckortrailer CargoInsurancepertruckortrailer	1000000.0	USD
CY2020	knx	Cargoinsuranceperoccurrence Cargoinsuranceperoccurrence	10000000.0	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	80060000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	50703000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	44357000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	19153000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	16616000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	22300000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	4248000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	5526000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	3124000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	103461000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	72845000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	69781000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	29640000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	28618000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	59508000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7292000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3712000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1639000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	9283000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-1377000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	461000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	46215000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	30953000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	61608000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	149676000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	103798000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	131389000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	117665000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	86935000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	117478000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	22423000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	17803000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	19256000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	452000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Contingencies Other IncomeTaxReconciliationTaxContingenciesOther	9588000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Contingencies Other IncomeTaxReconciliationTaxContingenciesOther	-940000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Contingencies Other IncomeTaxReconciliationTaxContingenciesOther	-5797000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	149676000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	103798000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	131389000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	81426000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	80019000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	5727000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	5478000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	7712000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	5769000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	17941000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	32284000	USD
CY2020Q4	knx	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Operating Lease Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOperatingLeaseLiabilities	29278000	USD
CY2019Q4	knx	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Operating Lease Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOperatingLeaseLiabilities	44231000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	10687000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	8762000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	152771000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	948262000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	176543000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	152771000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	176543000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	586349000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	550521000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	12629000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	11168000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	334618000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	345555000	USD
CY2020Q4	knx	Deferred Tax Liabilities Operating Lease Right Of Use Assets DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets	28259000	USD
CY2019Q4	knx	Deferred Tax Liabilities Operating Lease Right Of Use Assets DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets	41018000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	6857000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	0	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	968712000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	815941000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	771719000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	82100000	USD
CY2020	us-gaap	Foreign Earnings Repatriated ForeignEarningsRepatriated	23000000.0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4083000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	7423000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	7096000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	38000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1056000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1133000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3378000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	729000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2950000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4083000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	7423000	USD
CY2020Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	300000	USD
CY2019Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	400000	USD
CY2020	us-gaap	Debt Instrument Collateral Fee DebtInstrumentCollateralFee	3500000	USD
CY2019	us-gaap	Debt Instrument Collateral Fee DebtInstrumentCollateralFee	7200000	USD
CY2018	us-gaap	Debt Instrument Collateral Fee DebtInstrumentCollateralFee	8100000	USD
CY2020Q4	us-gaap	Unsecured Debt UnsecuredDebt	298907000	USD
CY2019Q4	us-gaap	Unsecured Debt UnsecuredDebt	364825000	USD
CY2020Q4	us-gaap	Unsecured Debt Current UnsecuredDebtCurrent	0	USD
CY2019Q4	us-gaap	Unsecured Debt Current UnsecuredDebtCurrent	364825000	USD
CY2020Q4	us-gaap	Unsecured Long Term Debt UnsecuredLongTermDebt	298907000	USD
CY2019Q4	us-gaap	Unsecured Long Term Debt UnsecuredLongTermDebt	0	USD
CY2020Q4	us-gaap	Unsecured Debt UnsecuredDebt	298907000	USD
CY2019Q4	us-gaap	Unsecured Debt UnsecuredDebt	364825000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	508907000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	643825000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	80456000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	120201000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	6544000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2897000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	360000	USD
CY2020	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	86640000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	360000	USD
CY2019	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	122738000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	16638000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	19878000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2896000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3048000	USD
CY2020	knx	Totalfinanceleasecost Totalfinanceleasecost	19534000	USD
CY2019	knx	Totalfinanceleasecost Totalfinanceleasecost	22926000	USD
CY2020	us-gaap	Lease Cost LeaseCost	106174000	USD
CY2019	us-gaap	Lease Cost LeaseCost	145664000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	49986000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	56699000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	31632000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	32894000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	18589000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	21542000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	7024000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	64121000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3491000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	3487000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	22810000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	23708000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	133532000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	202451000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	16184000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	11625000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	117348000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	190826000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	47496000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	52583000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	69852000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	138243000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	83675000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	121737000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	2896000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	3048000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	83910000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	115642000	USD
CY2020	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	45698000	USD
CY2019	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	46858000	USD
CY2020	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	1691000	USD
CY2019	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	2169000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Rolling Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextRollingTwelveMonths	41602000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	28596000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	15418000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	3103000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	587000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	373000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	89679000	USD
CY2020Q4	us-gaap	Accrued Professional Fees Current And Noncurrent AccruedProfessionalFeesCurrentAndNoncurrent	20200000	USD
CY2019Q4	us-gaap	Accrued Professional Fees Current And Noncurrent AccruedProfessionalFeesCurrentAndNoncurrent	121300000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	179585000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	86892000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	26594000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	16038000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12387000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4949000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3344000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3097000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	56342000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P2Y3M18D
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	868535	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	772522	shares
CY2019	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	221000	USD
CY2018	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	1685000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	618067	shares
CY2020Q4	us-gaap	Share Price SharePrice	41.82
CY2019Q4	us-gaap	Share Price SharePrice	35.84
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	382254	shares
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	443288	shares
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	533226	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	4929000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	5183000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	11745000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	10199000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	10478000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	10815000	USD
CY2020	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	1029000	USD
CY2020	knx	Maximum Amount For Which Common Stock Can Be Purchased By Employees During Period MaximumAmountForWhichCommonStockCanBePurchasedByEmployeesDuringPeriod	6250	USD
CY2020	knx	Maximum Amount For Which Common Stock Can Be Purchased By Employees In Any Calendar Year MaximumAmountForWhichCommonStockCanBePurchasedByEmployeesInAnyCalendarYear	25000	USD
CY2020	knx	Purchase Of Common Stock Under Employee Stock Purchase Plan PurchaseOfCommonStockUnderEmployeeStockPurchasePlan	0.05
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	169711000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	171541000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	177018000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	838000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	601000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	981000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	170549000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172142000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	177999000	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	63000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	603000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	47000	shares
CY2019	knx	Percentage Of Depreciation PercentageOfDepreciation	1.000
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	8915000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	9001000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	8995000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	8912000	USD
CY2020Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	77562000	USD
CY2020Q4	us-gaap	Equity Method Investments Fair Value Disclosure EquityMethodInvestmentsFairValueDisclosure	77562000	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	30878000	USD
CY2019Q4	us-gaap	Equity Method Investments Fair Value Disclosure EquityMethodInvestmentsFairValueDisclosure	30878000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	18675000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	18675000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	8722000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	8722000	USD
CY2020Q4	us-gaap	Long Term Line Of Credit LongTermLineOfCredit	210000000	USD
CY2020Q4	us-gaap	Long Term Line Of Credit LongTermLineOfCredit	210000000	USD
CY2019Q4	us-gaap	Long Term Line Of Credit LongTermLineOfCredit	279000000	USD
CY2019Q4	us-gaap	Long Term Line Of Credit LongTermLineOfCredit	279000000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	16200000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	16200000	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2020Q4	us-gaap	Accounts Receivable Related Parties Current AccountsReceivableRelatedPartiesCurrent	135000	USD
CY2020Q4	us-gaap	Accounts Payable Related Parties Current AccountsPayableRelatedPartiesCurrent	51000	USD
CY2019Q4	us-gaap	Accounts Receivable Related Parties Current AccountsReceivableRelatedPartiesCurrent	2889000	USD
CY2019Q4	us-gaap	Accounts Payable Related Parties Current AccountsPayableRelatedPartiesCurrent	2000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	Segment
CY2020	us-gaap	Revenues Revenues	4673863000	USD
CY2020	knx	Percentageof Revenue PercentageofRevenue	1.000
CY2019	us-gaap	Revenues Revenues	4843950000	USD
CY2019	knx	Percentageof Revenue PercentageofRevenue	1.000
CY2018	us-gaap	Revenues Revenues	5344066000	USD
CY2018	knx	Percentageof Revenue PercentageofRevenue	1.000
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	564438000	USD
CY2020	knx	Percentage Of Operating Income PercentageOfOperatingIncome	1.000
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	427438000	USD
CY2019	knx	Percentage Of Operating Income PercentageOfOperatingIncome	1.000
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	569043000	USD
CY2018	knx	Percentage Of Operating Income PercentageOfOperatingIncome	1.000
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	460775000	USD
CY2020	knx	Percentage Of Depreciation PercentageOfDepreciation	1.000
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	420082000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	387505000	USD
CY2018	knx	Percentage Of Depreciation PercentageOfDepreciation	1.000
CY2019	knx	Percentages Of Foreign Operations Consolidated Revenue PercentagesOfForeignOperationsConsolidatedRevenue	0.050
CY2020	knx	Percentages Of Foreign Operations Consolidated Revenue PercentagesOfForeignOperationsConsolidatedRevenue	0.050
CY2018	knx	Percentages Of Foreign Operations Consolidated Revenue PercentagesOfForeignOperationsConsolidatedRevenue	0.050
CY2019Q4	knx	Longlivedassetsofforeignoperations Longlivedassetsofforeignoperations	0.050
CY2020Q4	knx	Longlivedassetsofforeignoperations Longlivedassetsofforeignoperations	0.050
CY2020	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	0.100
CY2018	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	0.100
CY2019	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	0.100

Files In Submission

Name	View Source	Status
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0001492691-21-000016-index.html	Edgar Link	pending
0001492691-21-000016.txt	Edgar Link	pending
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$KNX
Knight-Swift Transportation Holdings Inc. Stock $knx

2020 Form 10-K Financial Statement

#000149269121000016 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$KNX Knight-Swift Transportation Holdings Inc. Stock $knx

2020 Form 10-K Financial Statement

#000149269121000016 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$KNX
Knight-Swift Transportation Holdings Inc. Stock $knx