Represents the amount of the additional fuel expense related to the fuel hedge contracts.

No definition available.

Name:	cvti_DerivativeAdditionalFuelExpense
Namespace Prefix:	cvti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of right to receive cash collateral under master netting arrangements that has been offset against derivative liabilities.

+ References

No definition available.

+ Details

Name:	cvti_DerivativeCollateralRightToReclaimCashNet
Namespace Prefix:	cvti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	cvti_Note13DerivativeInstrumentsDetailsLineItems
Namespace Prefix:	cvti_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of estimated annual fuel requirements hedged for the remainder of the period.

+ References

No definition available.

+ Details

Name:	cvti_PercentOfProjectedFuelRequirements
Namespace Prefix:	cvti_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

Name:	us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

+ Details

Name:	us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

+ Details

Name:	us-gaap_DerivativeNumberOfInstrumentsHeld
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The net gain (loss) relating to components of the gain (loss) on the cash flow hedging instrument excluded from the assessment of cash flow hedge effectiveness. Recognized in earnings.

+ References

+ Details

Name:	us-gaap_GainLossFromComponentsExcludedFromAssessmentOfCashFlowHedgeEffectivenessNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract measured in volume but not the derivative contract itself.

+ References

No definition available.

+ Details

Name:	us-gaap_UnderlyingDerivativeVolume
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DerivativeByNatureAxis=cvti_GallonsOfDieselMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_AdditionalFuelExpenseNoLongerDeemedToBeEffectiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_AdditionalFuelExpenseUnfavorableIneffectivenessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_ExpiredOrSoldContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=cvti_FuelRequirements2015Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=cvti_FuelRequirements2016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=cvti_FuelRequirements2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=cvti_HedgeContractsIneffectivenessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 13 - Derivative Instruments (Details) (USD $)	12 Months Ended
Note 13 - Derivative Instruments (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 13 - Derivative Instruments (Details) [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	$ 22,700,000	$ 1,400,000
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(3,100,000)	600,000	3,100,000
Gain (Loss) from Components Excluded from Assessment of Cash Flow Hedge Effectiveness, Net	100,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	8,000,000
Derivative, Collateral, Right to Reclaim Cash, Net	5,000,000	0.0
Gallons of Diesel [Member] \| Fuel Requirements 2015 [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative, Number of Instruments Held	12,600,000
Gallons of Diesel [Member] \| Fuel Requirements 2016 [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative, Number of Instruments Held	12,100,000
Gallons of Diesel [Member] \| Fuel Requirements 2017 [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative, Number of Instruments Held	3,000,000
Gallons of Diesel [Member] \| Minimum [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Underlying, Derivative Volume (in Dollars per Item)	3.08	3.29
Gallons of Diesel [Member] \| Maximum [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Underlying, Derivative Volume (in Dollars per Item)	1.58	2.72
Fuel Requirements 2015 [Member] \| Gallons of Diesel [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Percent of Projected Fuel Requirements	23.00%
Fuel Requirements 2016 [Member] \| Gallons of Diesel [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Percent of Projected Fuel Requirements	22.00%
Fuel Requirements 2017 [Member] \| Gallons of Diesel [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Percent of Projected Fuel Requirements	5.00%
Hedge Contracts Ineffectiveness [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative, Additional Fuel Expense	1,400,000
Expired or Sold contracts [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(1,500,000)
Additional Fuel Expense, no Longer Deemed to be Effective [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(1,400,000)
Additional Fuel Expense, Unfavorable Ineffectiveness [Member]
Note 13 - Derivative Instruments (Details) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (200,000)