v2.4.1.9

Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
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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Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. 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. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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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))

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. 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))

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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

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-Paragraph 1

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