Note 5 - Fair Value Measurement and Fair Value of Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2012
Accounts Receivable, Net	5.7
Allowance for Notes, Loans and Financing Receivable	0.1
Accounts Receivable Retainage	0.3
Minimum [Member]
Advances Granted on Accounts Receivable	80.00%
Maximum [Member]
Advances Granted on Accounts Receivable	90.00%

The amounts related to factored receivables that are withheld until the related receivables are collected.

No definition available.

Name:	cvti_AccountsReceivableRetainage
Namespace Prefix:	cvti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of each purchased receivable's face value advanced to the customer.

+ References

No definition available.

+ Details

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

- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.9)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.5)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

For an unclassified balance sheet, the valuation allowance relating to a written agreement to receive money (at a specified future date(s), consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_AllowanceForNotesReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant