XML 89 R74.htm IDEA: XBRL DOCUMENT v3.7.0.1

Warrants - Outstanding Warrants To Purchase Common Stock Warrants (Parenthetical) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Sep. 26, 2016	Sep. 25, 2016	Jan. 30, 2015
Private Placement [Member]
Class Of Warrant Or Right [Line Items]
Exercise Price		$ 4.00	$ 4.98
Subsequent Financing [Member]
Class Of Warrant Or Right [Line Items]
Exercise Price		4.00	4.98
Common Stock [Member]
Class Of Warrant Or Right [Line Items]
Exercise Price				$ 6.96
Common Stock [Member] | Private Placement [Member] | Accredited Investors [Member]
Class Of Warrant Or Right [Line Items]
Warrants, issued date	Apr. 14, 2016
Exercise Price		4.00	4.98
Common Stock [Member] | Private Placement [Member] | Placement Agents [Member]
Class Of Warrant Or Right [Line Items]
Warrants, issued date	Apr. 14, 2016
Common Stock [Member] | Subsequent Financing [Member]
Class Of Warrant Or Right [Line Items]
Warrants, issued date	Jun. 15, 2016
Exercise Price		$ 4.00	$ 4.98

X

- Definition

Date the warrants or rights are exercisable, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(3))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRighstDateFromWhichWarrantsOrRightsExercisable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=cdna_SubsequentFinancingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_TitleOfIndividualAxis=cdna_AccreditedInvestorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_TitleOfIndividualAxis=cdna_PlacementAgentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: