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_Note6DerivativeInstrumentsDetailsLineItems
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=56946850&loc=SL5624163-113959

+ Details

Name:	us-gaap_CashFlowHedgeDerivativeInstrumentAssetsAtFairValue
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=56946850&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=56946850&loc=SL5624177-113959

+ Details

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

- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

+ Details

Name:	us-gaap_GainLossOnCashFlowHedgeIneffectivenessNet
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_ExpiredOrSoldContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_FuelHedgeContractsFor2015FuelRequirementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_FuelHedgeContractsFor2016FuelRequirementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cvti_FuelHedgeContractsFor2017FuelRequirementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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 6 - Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Note 6 - Derivative Instruments (Details) [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	$ 21.8
Derivative, Collateral, Right to Reclaim Cash, Net	2.9		5.0
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(3.4)
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net	(0.1)
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	(8.3)
Hedge Contracts Ineffectiveness [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative, Additional Fuel Expense	(0.3)
Gallons of Diesel [Member] \| Maximum [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Underlying, Derivative Volume (in Dollars per US Gallon)	1.97	3.08
Gallons of Diesel [Member] \| Minimum [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Underlying, Derivative Volume (in Dollars per US Gallon)	1.44
Minimum [Member] \| Gallons of Diesel [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Underlying, Derivative Volume (in Dollars per US Gallon)		2.85
Fuel Hedge Contracts for 2015 Fuel Requirements [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative, Nonmonetary Notional Amount, Volume (in US Gallons)	9,500,000
Percent of Projected Fuel Requirements	22.90%
Fuel Hedge Contracts for 2016 Fuel Requirements [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative, Nonmonetary Notional Amount, Volume (in US Gallons)	12,100,000
Percent of Projected Fuel Requirements	21.90%
Fuel Hedge Contracts for 2017 Fuel Requirements [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative, Nonmonetary Notional Amount, Volume (in US Gallons)	7,600,000
Percent of Projected Fuel Requirements	13.70%
Expired or Sold contracts [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(3.4)
Additional Fuel Expense, no Longer Deemed to be Effective [Member]
Note 6 - Derivative Instruments (Details) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 0.3