CareDx, Inc. - 10-K filing on 2017-04-21

Subsequent Events - Additional Information (Detail)								1 Months Ended	12 Months Ended
Subsequent Events - Additional Information (Detail)	Dec. 31, 2017 USD ($)	Jul. 01, 2017 USD ($)	Apr. 19, 2017 shares	Mar. 15, 2017 USD ($) $ / shares shares	Mar. 02, 2017 USD ($)	Jul. 15, 2016 USD ($)	Apr. 25, 2016 USD ($)	Jan. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Apr. 18, 2017 $ / d	Jan. 30, 2015 $ / shares shares
Subsequent Event [Line Items]
Damages sought						$ 1,300,000
Proceeds from debt, net of issuance costs									$ 0	$ 15,625,000	$ 0
Debt instrument maturity date									Dec. 01, 2018
Common Stock [Member]
Subsequent Event [Line Items]
Warrant to purchase stock, shares \| shares													34,483
Warrant to purchase of stock, per share \| $ / shares													$ 6.96
Oberland Complaint [Member]
Subsequent Event [Line Items]
Damages sought							$ 1,400,000
Amount accrued for claim							$ 1,400,000		$ 600,000
Subsequent Event [Member] \| JGB Debt [Member]
Subsequent Event [Line Items]
Aggregate principal amount				$ 27,800,000
Warrant to purchase stock, shares \| shares				1,250,000
Proceeds from debt, net of issuance costs				$ 24,000,000
Pay-off of term debt				11,200,000
Minimum cash requirement				$ 9,400,000
Debt instrument maturity date				Feb. 28, 2020
Interest rate				9.50%
Conversion price per share \| $ / shares				$ 4.56
Debt conversion description				Additionally, after September 1, 2017, upon the satisfaction of certain conditions, including the volume weighted average price of the Company’s common stock exceeding 250% of the Conversion Price for twenty consecutive trading days, the Company can require that the Debentures be converted into shares of the Company’s common stock, subject to certain limitations.
Debt, possible redemption amount after March 1, 2018				$ 937,500
Debt redemption description				Commencing on March 1, 2018, each of the holders of the Debentures shall have the right, at its option, to require the Company to redeem up to $937,500 of the outstanding principal amount of its Debenture per month. The Company will be required to promptly, but in any event no more than one trading day after the holder delivers a redemption notice to the Company, pay the applicable redemption amount in cash or, at the Company’s election and subject to certain conditions, in shares of the Company’s common stock. If the Company elects to pay the redemption amount in shares of the Company’s common stock, then the shares will be delivered based on a price equal to the lowest of (a) 88% of the average of the three lowest volume weighted average prices of the Company’s common stock over the prior 20 trading days, (b) 88% of the prior trading day’s volume weighted average price, or (c) the Conversion Price. The Company may only opt for payment in shares of the Company’s common stock if certain conditions are met.
Percentage of average three lowest volume weighted average prices of common stock if elected to pay in shares				88.00%
Percentage of prior trading day's volume weighted average price if elected to pay in shares				88.00%
Warrant to purchase of stock, per share \| $ / shares				$ 5.00
Warrants, issued date				Sep. 16, 2017
Warrants expiration date				Sep. 15, 2022
Number of shares to seek shareholders approval to issue additional common stock \| shares				4,269,522
Percentage of gross proceeds from sale of debentures as fee of placement				3.00%
Date of first required payment				2018-03
Warrants exercisable period from grant date				185 days
Warrants, term				5 years 6 months
Accruing liquidated damages payable amount per day \| $ / d												7,000
Subsequent Event [Member] \| JGB Debt [Member] \| If Debenture is accelerated prior to March 1, 2018 [Member]
Subsequent Event [Line Items]
Percentage of debt principal and interest outstanding repayment				115.00%
Subsequent Event [Member] \| JGB Debt [Member] \| If Debenture is accelerated after March 1, 2018 but prior to March 1, 2019 [Member]
Subsequent Event [Line Items]
Percentage of debt principal and interest outstanding repayment				108.00%
Subsequent Event [Member] \| JGB Debt [Member] \| If Debenture is accelerated after March 1, 2019 [Member]
Subsequent Event [Line Items]
Percentage of debt principal and interest outstanding repayment				105.00%
Subsequent Event [Member] \| Oberland Complaint [Member]
Subsequent Event [Line Items]
Settlement amount					$ (600,000)
Subsequent Event [Member] \| Maximum [Member] \| Common Stock [Member]
Subsequent Event [Line Items]
Restriction on sale of common stock \| shares			8,534,261
Subsequent Event [Member] \| Maximum [Member] \| JGB Debt [Member]
Subsequent Event [Line Items]
Required repayment of debt per month				$ 900,000
Conexio [Member] \| Scenario Forecast [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Consideration to be paid for finished goods acquired		$ 300,000
Consideration to be paid for unfinished inventory acquired	$ 200,000
Conexio [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Acquisition related quarterly payments, percentage on gross revenue								20.00%
Conexio [Member] \| Subsequent Event [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Acquisition related quarterly payments on gross revenue								$ 700,000
Obligations and liabilities assumed for product warranty claims								$ 35,000