Subsequent Events Subsequent Events	12 Months Ended
Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In January 2018, the Company entered into a sales agreement with a sales agent to sell shares of the Company's common stock through an "at the market" equity offering program for up to $40.0 million in gross cash proceeds. The sales agreement allows the Company to set the parameters for the sale of shares, including the number of shares to be issued, the time period during which sales are requested to be made, limits on the number of shares that may be sold in any one trading day and a minimum price below which sales may not be made. Under the terms of the Sales Agreement, commission expenses to the sales agent will be 3% of the gross sales price per share sold through the sales agent. The Sales Agreement shall automatically terminate upon the issuance and sale of placement shares equaling sales proceeds of $40.0 million and may be terminated earlier by either the Company or the sales agent upon five days’ notice. In January 2018, the Company, as borrower, entered into a $15.0 million secured revolving loan facility, with availability subject to a borrowing base consisting of eligible accounts receivable. The agreement matures in January 2021, at which time the outstanding principal will become due and payable. Interest on borrowings is payable monthly and accrues at a yearly rate equal to the greater of the prime rate, as reported in the Wall Street Journal, plus 0.50% or 4.75%. During an event of default amounts drawn accrue interest at a yearly rate equal to 8.75%. Obligations under the agreement are collateralized by substantially all of the Company’s assets. In February 2018, the Company and Celgene entered into an amendment to their collaboration agreement in which Celgene agreed to provide the Company additional funding for work intended to enable a subtype and prognostic indication for the test being developed under the agreement for Celgene’s drug REVLIMID. In addition, the amendment provides an additional milestone payment to the Company payable upon achievement of certain regulatory activities and timelines. In connection with this amendment, the Company agreed to remove the right to receive payments from Celgene in the event commercial sales of the companion diagnostic test do not exceed certain pre-specified minimum annual revenues during the first three years following regulatory approval. In addition, the amendment allows Celgene, at its election, to use trial samples with additional technologies for companion diagnostics.

Subsequent Events

In January 2018, the Company entered into a sales agreement with a sales agent to sell shares of the Company's common stock through an "at the market" equity offering program for up to $40.0 million in gross cash proceeds. The sales agreement allows the Company to set the parameters for the sale of shares, including the number of shares to be issued, the time period during which sales are requested to be made, limits on the number of shares that may be sold in any one trading day and a minimum price below which sales may not be made. Under the terms of the Sales Agreement, commission expenses to the sales agent will be 3% of the gross sales price per share sold through the sales agent. The Sales Agreement shall automatically terminate upon the issuance and sale of placement shares equaling sales proceeds of $40.0 million and may be terminated earlier by either the Company or the sales agent upon five days’ notice.

In January 2018, the Company, as borrower, entered into a $15.0 million secured revolving loan facility, with availability subject to a borrowing base consisting of eligible accounts receivable. The agreement matures in January 2021, at which time the outstanding principal will become due and payable. Interest on borrowings is payable monthly and accrues at a yearly rate equal to the greater of the prime rate, as reported in the Wall Street Journal, plus 0.50% or 4.75%. During an event of default amounts drawn accrue interest at a yearly rate equal to 8.75%. Obligations under the agreement are collateralized by substantially all of the Company’s assets.

In February 2018, the Company and Celgene entered into an amendment to their collaboration agreement in which Celgene agreed to provide the Company additional funding for work intended to enable a subtype and prognostic indication for the test being developed under the agreement for Celgene’s drug REVLIMID. In addition, the amendment provides an additional milestone payment to the Company payable upon achievement of certain regulatory activities and timelines. In connection with this amendment, the Company agreed to remove the right to receive payments from Celgene in the event commercial sales of the companion diagnostic test do not exceed certain pre-specified minimum annual revenues during the first three years following regulatory approval. In addition, the amendment allows Celgene, at its election, to use trial samples with additional technologies for companion diagnostics.