v2.4.1.9

Summary of Operations by Geographic Area (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers | $ 22,326 us-gaap_SalesRevenueNet | $ 34,821 us-gaap_SalesRevenueNet | $ 36,797 us-gaap_SalesRevenueNet | $ 24,855 us-gaap_SalesRevenueNet | $ 19,875 us-gaap_SalesRevenueNet | $ 33,101 us-gaap_SalesRevenueNet | $ 35,565 us-gaap_SalesRevenueNet | $ 25,397 us-gaap_SalesRevenueNet | $ 118,799 us-gaap_SalesRevenueNet | $ 113,938 us-gaap_SalesRevenueNet | $ 113,521 us-gaap_SalesRevenueNet
Operating income (loss) |  |  |  |  |  |  |  |  | 79 us-gaap_OperatingIncomeLoss | 62 us-gaap_OperatingIncomeLoss | (2,133)us-gaap_OperatingIncomeLoss
Assets | 49,767 us-gaap_Assets |  |  |  | 46,244 us-gaap_Assets |  |  |  | 49,767 us-gaap_Assets | 46,244 us-gaap_Assets |
UNITED STATES |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 92,686 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US | 87,504 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US | 85,374 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US
Operating income (loss) |  |  |  |  |  |  |  |  | 1,289 us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_US | 1,085 us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_US | (459)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_US
Assets | 40,819 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_US |  |  |  | 36,339 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_US |  |  |  | 40,819 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_US | 36,339 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_US | 38,341 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_US
CANADA |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 26,113 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_CA | 26,434 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_CA | 28,147 us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_CA
Operating income (loss) |  |  |  |  |  |  |  |  | (1,195)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_CA | (1,122)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_CA | (1,607)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = country_CA
Assets | 8,703 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_CA |  |  |  | 9,554 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_CA |  |  |  | 8,703 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_CA | 9,554 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_CA | 11,009 us-gaap_Assets / us-gaap_StatementGeographicalAxis = country_CA
Other Countries |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating income (loss) |  |  |  |  |  |  |  |  | (15)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember | 99 us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember | (67)us-gaap_OperatingIncomeLoss / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember
Assets | $ 245 us-gaap_Assets / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember |  |  |  | $ 351 us-gaap_Assets / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember |  |  |  | $ 245 us-gaap_Assets / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember | $ 351 us-gaap_Assets / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember | $ 309 us-gaap_Assets / us-gaap_StatementGeographicalAxis = crv_OtherCountriesMember

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