Note 4 - Discontinued Operations (Details Textual) - Transport Financial Services [Member] - Discontinued Operations, Disposed of by Sale [Member] - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Jul. 08, 2020
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net			$ 103,300
Disposal Group Including Discontinued Operation Accounts Notes And Loans Receivable Gross			108,700
Disposal Group, Including Discontinued Operation, Allowance			$ 5,400
Cash Provided by (Used in) Operating Activities, Discontinued Operations	$ 0	$ 0

Represents the disposal group, including discontinued operation accounts notes and loans receivable, gross.

No definition available.

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Namespace Prefix:	cvlg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance on accounts receivable, attributable to disposal group held for sale or disposed of, classified as current.

+ References

No definition available.

+ Details

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Namespace Prefix:	cvlg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3521-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

+ Details

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

- Definition

Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759

+ Details

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

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: