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- Definition

Contractual Obligation Maturity Date

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- Definition

Fair Value Input Probability Of Achievement

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- Definition

Fair Value Measurements Inter Transfers Between Levels

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- Definition

Number of Commercial Tests

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- Definition

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

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-Publisher FASB

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- Definition

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

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- Definition

Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Net fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as assets, net of those classified as liabilities.

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Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended			0 Months Ended			1 Months Ended
	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014 CommercialTests	Jun. 30, 2014	Apr. 17, 2014	Jul. 31, 2014
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Transfers between Level 1, Level 2 and Level 3 categories during the periods		$ 0
Estimated fair value of embedded derivative liabilities	239,000					239,000
Fair value of derivative	120,000					120,000
Gain on derivative	119,000	(118,000)	0	0
Illumina, Inc. [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Subordinated convertible promissory note issued							5,000,000
ImmuMetrix, Inc. [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Number of commercial tests involving the measurement of cfDNA to be completed		2,500			2,500
Milestone description		The milestone will be achieved if the Company completes 2,500 commercial tests involving the measurement of cfDNA in organ transplant recipients in the United States no later than six years after the closing date of the acquisition.
Contingent consideration maturity date		Jun. 10, 2020
IPO [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Change in control for repayment						5.00%	10.00%
Fair value of derivative								0
Gain on derivative								$ 120,000
Contingent consideration [Member] \| ImmuMetrix, Inc. [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Contingent obligation to issue common stock					227,845
Milestone description		The issuance will occur if the Company completes 2,500 commercial tests involving the measurement of cfDNA in organ transplant recipients in the United States by June 10, 2020.
Probability of the achievement					65.00%