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- Definition

Number of Commercial Tests

+ References

No definition available.

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- Definition

Percentage of probability in achieving contingency condition.

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No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents a description of such arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
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- 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.

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- Definition

Amount of unrealized gain (loss) recognized in the income statement for a financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
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Fair Value Measurements - Additional Information (Detail)	3 Months Ended			12 Months Ended
	Mar. 31, 2018 USD ($) CommercialTest shares	Mar. 27, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Transfers between Level 1, Level 2 and Level 3 categories during the periods	$ 0			$ 0
Change in estimated fair value of contingent consideration	$ 144,000		$ (221,000)
Change in fair market value of derivative liability		$ 2,500,000	800,000
ImmuMetrix, Inc. [Member] \| Contingent Consideration Liability [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent obligation to issue common stock \| shares	227,845			227,845
Milestone description	The issuance of shares will occur if the Company completes 2,500 commercial tests involving the measurement of dd-cfDNA in organ transplant recipients in the United States by June 10, 2020.
Number of commercial tests involving the measurement of cfDNA to be completed \| CommercialTest	2,500
Change in estimated fair value of contingent consideration	$ 100,000		$ (200,000)
ImmuMetrix, Inc. [Member] \| Minimum [Member] \| Contingent Consideration Liability [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of probability in achieving contingency condition	80.00%
ImmuMetrix, Inc. [Member] \| Maximum [Member] \| Contingent Consideration Liability [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of probability in achieving contingency condition	100.00%