v2.4.1.9

Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Detail) (USD $) | Dec. 31, 2014 | Dec. 31, 2013
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Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized | 0us-gaap_TemporaryEquitySharesAuthorized | 6,417,954us-gaap_TemporaryEquitySharesAuthorized
Shares Outstanding | 0us-gaap_TemporaryEquitySharesOutstanding | 5,155,673us-gaap_TemporaryEquitySharesOutstanding
Carrying Value | $ 0us-gaap_TemporaryEquityCarryingAmountAttributableToParent | $ 135,202,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent
Liquidation Value | 0us-gaap_TemporaryEquityLiquidationPreference | 137,221,000us-gaap_TemporaryEquityLiquidationPreference
Series A Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 79,708us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesAConvertiblePreferredStockMember
Shares Outstanding |  | 16,930us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesAConvertiblePreferredStockMember
Carrying Value |  | 267,000,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesAConvertiblePreferredStockMember
Liquidation Value |  | 290,000,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesAConvertiblePreferredStockMember
Series B Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 145,221us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesBConvertiblePreferredStockMember
Shares Outstanding |  | 16,065us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesBConvertiblePreferredStockMember
Carrying Value |  | 826,143,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesBConvertiblePreferredStockMember
Liquidation Value |  | 853,143,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesBConvertiblePreferredStockMember
Series C Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 850,899us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesCConvertiblePreferredStockMember
Shares Outstanding |  | 829,209us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesCConvertiblePreferredStockMember
Carrying Value |  | 14,139,373,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesCConvertiblePreferredStockMember
Liquidation Value |  | 14,200,373,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesCConvertiblePreferredStockMember
Series D Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 965,672us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesDConvertiblePreferredStockMember
Shares Outstanding |  | 877,880us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesDConvertiblePreferredStockMember
Carrying Value |  | 18,459,000,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesDConvertiblePreferredStockMember
Liquidation Value |  | 20,024,985,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesDConvertiblePreferredStockMember
Series E Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 857,323us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesEConvertiblePreferredStockMember
Shares Outstanding |  | 835,547us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesEConvertiblePreferredStockMember
Carrying Value |  | 26,423,000,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesEConvertiblePreferredStockMember
Liquidation Value |  | 26,499,984,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesEConvertiblePreferredStockMember
Series F Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 1,463,859us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesFConvertiblePreferredStockMember
Shares Outstanding |  | 1,441,053us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesFConvertiblePreferredStockMember
Carrying Value |  | 50,443,000,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesFConvertiblePreferredStockMember
Liquidation Value |  | 50,541,097,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesFConvertiblePreferredStockMember
Series G Convertible Preferred Stock [Member] |  |
Summary Activity In Gold Bullion [Line Items] |  |
Shares Authorized |  | 2,055,272us-gaap_TemporaryEquitySharesAuthorized / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember
Shares Outstanding |  | 1,138,989us-gaap_TemporaryEquitySharesOutstanding / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember
Carrying Value |  | 24,644,515,000us-gaap_TemporaryEquityCarryingAmountAttributableToParent / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember
Liquidation Value |  | $ 24,811,238,000us-gaap_TemporaryEquityLiquidationPreference / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember

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- Definition The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.27(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 28 -Subparagraph b -Article 5 + Details
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