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Balance Sheet Components - Additional Information (Detail) (USD $)
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12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Balance Sheet Components [Line Items] | |||
| Depreciation and amortization expense | $ 512,000us-gaap_DepreciationDepletionAndAmortization | $ 663,000us-gaap_DepreciationDepletionAndAmortization | $ 1,072,000us-gaap_DepreciationDepletionAndAmortization |
| Accumulated amortization | 11,092,000us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment | 10,902,000us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment | |
| Amortization expense, included in depreciation and amortization expense | 59,000us-gaap_AdjustmentForAmortization | 26,000us-gaap_AdjustmentForAmortization | 70,000us-gaap_AdjustmentForAmortization |
| Laboratory equipment and computer and office equipment [Member] | |||
| Balance Sheet Components [Line Items] | |||
| Assets purchased under capital leases | 1,631,000us-gaap_CapitalLeasedAssetsGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cdna_LaboratoryComputerAndOfficeEquipmentMember |
1,439,000us-gaap_CapitalLeasedAssetsGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cdna_LaboratoryComputerAndOfficeEquipmentMember |
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| Accumulated amortization | $ 1,473,000us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cdna_LaboratoryComputerAndOfficeEquipmentMember |
$ 1,414,000us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cdna_LaboratoryComputerAndOfficeEquipmentMember |
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- Details
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- Definition
Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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