Merck GHI Financing	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Common Stock And Note Purchase Agreement [Abstract]
Merck GHI Financing	In July 2015, in connection with the Merger, the Company entered into a Purchase Agreement with MGHIF, pursuant to which MGHIF purchased 45,454 shares of common stock of the Company at $110.00 per share for gross proceeds of $5.0 million. Pursuant to the Purchase Agreement, the Company also issued to MGHIF an 8% Senior Secured Promissory Note (the "MGHIF Note") in the principal amount of $1.0 million with a two-year maturity date from the date of issuance. The Company's obligations under the MGHIF Note are secured by a lien on all of the Company's assets. Under the Purchase Agreement, MGHIF has the right to participate in future securities offerings made by the Company. Also in July 2015, the Company entered into a Registration Rights Agreement with MGHIF and certain stockholders, which will require the Company to register for resale by such holders in the future, such shares of Company common stock that cannot be sold under an exemption from such registration. The Company incurred issuance costs of approximately $50,000 related to the financing. Approximately $8,000 of the issuance costs were deferred as debt issuance costs and netted against notes payable in the accompanying condensed consolidated balance sheets is a result of the Company's adoption of the new accounting guidance in 2016, and are being amortized as interest expense over the life of the MGHIF Note. The remaining $42,000 of issuance costs were charged to additional paid-in capital. On June 6, 2017, the promissory note was amended and restated, and the maturity date of the A&R MGHIF Note was extended by one year to July 14, 2018. As consideration for the agreement to extend the maturity date, the Company issued an amended and restated secured promissory note to MGHIF that (1) increased the interest rate to ten percent (10%) per annum and (2) provided for the issuance of common stock warrants to purchase 13,119 shares of its common stock to MGHIF . The warrants issued to MGHIF each have a five year term from issuance, are first exercisable on the date that is six months after the date of issuance and have an exercise price equal $19.50 which represents 110% of the closing price of the Company's common stock on the date of issuance. The A&R MGHIF Note was treated as a debt modification and as such the issuance date fair value of the warrants is deferred and amortized as incremental interest expense over the term of A&R MGHIF Note. The warrants are classified as mark to market liabilities under ASC 480, Distinguishing Liabilities from Equity, due to certain put features that allow the holder to put the warrant back to the Company for cash equal to the Black-Scholes value of the warrant upon a change of control or fundamental transaction, as defined in the agreement. The warrants had an issuance date fair value of approximately $0.1 million which was calculated using the Black-Scholes model. The estimated fair value of the A&R MGHIF Note was $1.0 million as of September 30, 2017 and December 31, 2016 which approximates the carry value given the short time lapse since modification, prevailing interest rates and maturity date	On July 14, 2015, as a condition of the Merger, the Company entered into the Purchase Agreement with Merck GHI, pursuant to which Merck GHI purchased 45,454 shares of common stock of the Company at $110.00 per share for gross proceeds of $5.0 million. Pursuant to the Purchase Agreement, the Company also issued to Merck GHI a 8% Senior Secured Promissory Note (the "Merck Note") in the principal amount of $1.0 million with a two-year maturity date from the date of issuance. The Company's obligations under the Merck Note are secured by a lien on all of the Company's assets. Under the Purchase Agreement, Merck GHI has the right to participate in future securities offerings made by the Company. Also in July 2015, the Company entered into a Registration Rights Agreement with Merck GHI and the AdvanDx stockholders who received shares of the Company's common stock in the Merger, which will require the Company to register for resale by such holders in the future, such shares of Company common stock that cannot be sold under an exemption from such registration. The Company incurred issuance costs of approximately $50,000 related to the financing. Approximately $8,000 of the issuance costs were deferred as debt issuance costs and netted against notes payable in the accompanying consolidated balance sheets as a result of the Company's adoption of the new accounting guidance in 2016 (see Note 3), and are being amortized as interest expense over the life of the Merck Note. The remaining $42,000 of issuance costs were charged to additional paid-in capital.

Merck GHI Financing

9 Months Ended

12 Months Ended

Sep. 30, 2017

Dec. 31, 2016

Common Stock And Note Purchase Agreement [Abstract]

In July 2015, in connection with the Merger, the Company entered into a Purchase Agreement with MGHIF, pursuant to which MGHIF purchased 45,454 shares of common stock of the Company at $110.00 per share for gross proceeds of $5.0 million. Pursuant to the Purchase Agreement, the Company also issued to MGHIF an 8% Senior Secured Promissory Note (the "MGHIF Note") in the principal amount of $1.0 million with a two-year maturity date from the date of issuance. The Company's obligations under the MGHIF Note are secured by a lien on all of the Company's assets. Under the Purchase Agreement, MGHIF has the right to participate in future securities offerings made by the Company. Also in July 2015, the Company entered into a Registration Rights Agreement with MGHIF and certain stockholders, which will require the Company to register for resale by such holders in the future, such shares of Company common stock that cannot be sold under an exemption from such registration.

The Company incurred issuance costs of approximately $50,000 related to the financing. Approximately $8,000 of the issuance costs were deferred as debt issuance costs and netted against notes payable in the accompanying condensed consolidated balance sheets is a result of the Company's adoption of the new accounting guidance in 2016, and are being amortized as interest expense over the life of the MGHIF Note. The remaining $42,000 of issuance costs were charged to additional paid-in capital.

On June 6, 2017, the promissory note was amended and restated, and the maturity date of the A&R MGHIF Note was extended by one year to July 14, 2018. As consideration for the agreement to extend the maturity date, the Company issued an amended and restated secured promissory note to MGHIF that (1) increased the interest rate to ten percent (10%) per annum and (2) provided for the issuance of common stock warrants to purchase 13,119 shares of its common stock to MGHIF . The warrants issued to MGHIF each have a five year term from issuance, are first exercisable on the date that is six months after the date of issuance and have an exercise price equal $19.50 which represents 110% of the closing price of the Company's common stock on the date of issuance.

The A&R MGHIF Note was treated as a debt modification and as such the issuance date fair value of the warrants is deferred and amortized as incremental interest expense over the term of A&R MGHIF Note. The warrants are classified as mark to market liabilities under ASC 480, Distinguishing Liabilities from Equity, due to certain put features that allow the holder to put the warrant back to the Company for cash equal to the Black-Scholes value of the warrant upon a change of control or fundamental transaction, as defined in the agreement. The warrants had an issuance date fair value of approximately $0.1 million which was calculated using the Black-Scholes model.

The estimated fair value of the A&R MGHIF Note was $1.0 million as of September 30, 2017 and December 31, 2016 which approximates the carry value given the short time lapse since modification, prevailing interest rates and maturity date

On July 14, 2015, as a condition of the Merger, the Company entered into the Purchase Agreement with Merck GHI, pursuant to which Merck GHI purchased 45,454 shares of common stock of the Company at $110.00 per share for gross proceeds of $5.0 million. Pursuant to the Purchase Agreement, the Company also issued to Merck GHI a 8% Senior Secured Promissory Note (the "Merck Note") in the principal amount of $1.0 million with a two-year maturity date from the date of issuance. The Company's obligations under the Merck Note are secured by a lien on all of the Company's assets. Under the Purchase Agreement, Merck GHI has the right to participate in future securities offerings made by the Company. Also in July 2015, the Company entered into a Registration Rights Agreement with Merck GHI and the AdvanDx stockholders who received shares of the Company's common stock in the Merger, which will require the Company to register for resale by such holders in the future, such shares of Company common stock that cannot be sold under an exemption from such registration.

The Company incurred issuance costs of approximately $50,000 related to the financing. Approximately $8,000 of the issuance costs were deferred as debt issuance costs and netted against notes payable in the accompanying consolidated balance sheets as a result of the Company's adoption of the new accounting guidance in 2016 (see Note 3), and are being amortized as interest expense over the life of the Merck Note. The remaining $42,000 of issuance costs were charged to additional paid-in capital.