v2.4.1.9

Property and Equipment Estimated Useful Lives (Detail) | 12 Months Ended
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Dec. 31, 2014
Buildings and improvements | Minimum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 12 years
Buildings and improvements | Maximum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 40 years
Warehouse and office equipment | Minimum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 5 years
Warehouse and office equipment | Maximum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 7 years
Automobiles | Minimum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 3 years
Automobiles | Maximum |
Property Plant and Equipment Estimated Useful Lives [Line Items] |
Property, Plant and Equipment, Estimated Useful Lives | 5 years

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- Details
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Namespace Prefix: | crv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_AutomobilesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingAndBuildingImprovementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |