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v3.20.2

Note 4 - Segment Information (Details Textual) | 6 Months Ended
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Jun. 30, 2020
Number of Asset-based Operating Fleets Aggregated in a Segment | 4

X
- Definition The number of asset-based operating fleets that are aggregated in a segment because they have similar economic characteristics and meet the aggregation criteria. + References No definition available. + Details
Name: | cvlg_NumberOfAssetbasedOperatingFleetsAggregatedInASegment
Namespace Prefix: | cvlg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration