Collaboration Agreements	9 Months Ended
Sep. 30, 2016
Deferred Revenue Disclosure [Abstract]
Collaboration Agreements	Collaboration Agreements The Company uses a proportional performance model to recognize collaboration revenue over the Company’s performance period for each collaboration agreement. Costs incurred to date compared to total expected costs are used to determine proportional performance, as this is considered to be representative of the delivery of outputs under the arrangement. Revenue recognized at any point in time is limited to cash received and amounts contractually due. Changes in estimates of total expected costs are accounted for prospectively as a change in estimate. All amounts received or due are classified as collaboration revenue as they are earned. Celgene Corporation In March 2014, the Company entered into a collaboration agreement with Celgene Corporation (“Celgene”) to develop, seek regulatory approval for, and commercialize a companion diagnostic assay for use in screening patients with Diffuse Large B-Cell Lymphoma. The Company is eligible to receive payments totaling up to $45.0 million, of which $5.8 million was received as an upfront payment upon delivery of certain information to Celgene, $17.0 million is for potential success-based development and regulatory milestones, and the remainder is for potential commercial payments in the event sales of the test do not exceed certain pre-specified minimum annual revenue during the first three years following regulatory approval. In October 2015, the parties amended the collaboration agreement to include additional countries to conduct clinical trials and in return the Company received an upfront payment of $1.6 million in December 2015. The Company will retain all commercial rights to the diagnostic test developed under this collaboration, subject to certain backup rights granted to Celgene to commercialize the diagnostic test in a particular country if the Company elects to cease distribution or elects not to distribute the diagnostic in such country. Assuming success in the clinical trial process, and subject to regulatory approval, the Company will market and sell the diagnostic assay. The Company achieved and was paid for milestones totaling $6.0 million during 2014. The process of successfully developing a product candidate, obtaining regulatory approval and ultimately commercializing a product candidate is highly uncertain and the attainment of any additional milestones is therefore uncertain and difficult to predict. In addition, certain milestones are outside the Company’s control and are dependent on the performance of Celgene and the outcome of a clinical trial and related regulatory processes. Accordingly, the Company is not able to reasonably estimate when, if at all, any additional milestone payments may be payable to the Company by Celgene. The Company recognized collaboration revenue related to the Celgene agreement of $0.6 million and $0.2 million for the three months ended September 30, 2016 and 2015, respectively, and $2.3 million and $1.2 million for the nine months ended September 30, 2016 and 2015, respectively. At September 30, 2016, the Company had recorded $6.1 million of deferred revenue related to the Celgene collaboration, of which $1.8 million is estimated to be recognizable as revenue within one year. Merck & Co., Inc. In May 2015, the Company entered into a clinical research collaboration agreement with Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (“Merck”), to develop an assay intended to optimize immune-related gene expression signatures and evaluate the potential to predict benefit from Merck’s anti-PD-1therapy, KEYTRUDA. Under the terms of the collaboration agreement, the Company was eligible to receive up to $4.0 million, of which $2.0 million was received as an upfront payment in July 2015 and $1.9 million was received as development payments during 2015. In February 2016, the Company expanded its collaboration with Merck by entering into a new development collaboration agreement to clinically develop and commercialize a novel diagnostic test, based on an optimized gene expression signature, to predict response to KEYTRUDA in multiple tumor types. Under the terms of the new collaboration agreement, the Company received $12.0 million upfront as a technology access fee, will receive additional development funding, and is eligible to receive up to $12.0 million of near-term preclinical milestone payments, of which $8.5 million was achieved and received during the nine months ended September 30, 2016, and other potential downstream regulatory milestone payments. The Company recognized collaboration revenue of $2.2 million and $6.1 million related to the Merck agreement for the three and nine months ended September 30, 2016, respectively, and $1.6 million and $1.8 million for the three and nine months ended September 30, 2015, respectively. As of September 30, 2016, the Company had recorded $22.4 million of deferred revenue related to the Merck collaboration, $7.7 million of which is estimated to be recognized as revenue within one year. Medivation, Inc. and Astellas Pharma, Inc. In January 2016, the Company entered into a collaboration agreement with Medivation, Inc. ("Medivation") and Astellas Pharma Inc. (“Astellas”) to pursue the translation of a novel gene expression signature algorithm discovered by Medivation into a companion diagnostic assay using the nCounter Analysis System. Under the terms of the collaboration agreement, the Company will modify its PAM50-based Prosigna Breast Cancer Assay for potential use as a companion diagnostic test for XTANDI (enzalutamide) for triple negative breast cancer. XTANDI is currently approved by the U.S. Food and Drug Administration for the treatment of metastatic castration-resistant prostate cancer. The modified Prosigna test will be based upon data from a Phase 2 trial conducted by Medivation and Astellas that evaluated enzalutamide in patients with triple negative breast cancer. Under the terms of the collaboration agreement, the Company will be responsible for developing and validating the diagnostic test and, if the parties thereafter determine to proceed, will also be responsible for seeking regulatory approval for and commercializing the test. During 2016, the Company received $6.0 million upfront for technology access, $6.0 million in pre-clinical milestones, and is eligible to receive up to $10.0 million in development funding over the term of the agreement, in addition to other potential downstream milestone payments. The Company recognized collaboration revenue of $1.5 million and $3.6 million related to the Medivation/Astellas agreement for the three and nine months ended September 30, 2016, respectively, and none for the three and nine months ended September 30, 2015. As of September 30, 2016, the Company had recorded $10.8 million of deferred revenue related to the Medivation/Astellas collaboration, $4.1 million of which is estimated to be recognized as revenue within one year.

Collaboration Agreements

The Company uses a proportional performance model to recognize collaboration revenue over the Company’s performance period for each collaboration agreement. Costs incurred to date compared to total expected costs are used to determine proportional performance, as this is considered to be representative of the delivery of outputs under the arrangement. Revenue recognized at any point in time is limited to cash received and amounts contractually due. Changes in estimates of total expected costs are accounted for prospectively as a change in estimate. All amounts received or due are classified as collaboration revenue as they are earned.

Celgene Corporation

In March 2014, the Company entered into a collaboration agreement with Celgene Corporation (“Celgene”) to develop, seek regulatory approval for, and commercialize a companion diagnostic assay for use in screening patients with Diffuse Large B-Cell Lymphoma. The Company is eligible to receive payments totaling up to $45.0 million, of which $5.8 million was received as an upfront payment upon delivery of certain information to Celgene, $17.0 million is for potential success-based development and regulatory milestones, and the remainder is for potential commercial payments in the event sales of the test do not exceed certain pre-specified minimum annual revenue during the first three years following regulatory approval. In October 2015, the parties amended the collaboration agreement to include additional countries to conduct clinical trials and in return the Company received an upfront payment of $1.6 million in December 2015.

The Company will retain all commercial rights to the diagnostic test developed under this collaboration, subject to certain backup rights granted to Celgene to commercialize the diagnostic test in a particular country if the Company elects to cease distribution or elects not to distribute the diagnostic in such country. Assuming success in the clinical trial process, and subject to regulatory approval, the Company will market and sell the diagnostic assay.

The Company achieved and was paid for milestones totaling $6.0 million during 2014. The process of successfully developing a product candidate, obtaining regulatory approval and ultimately commercializing a product candidate is highly uncertain and the attainment of any additional milestones is therefore uncertain and difficult to predict. In addition, certain milestones are outside the Company’s control and are dependent on the performance of Celgene and the outcome of a clinical trial and related regulatory processes. Accordingly, the Company is not able to reasonably estimate when, if at all, any additional milestone payments may be payable to the Company by Celgene.

The Company recognized collaboration revenue related to the Celgene agreement of $0.6 million and $0.2 million for the three months ended September 30, 2016 and 2015, respectively, and $2.3 million and $1.2 million for the nine months ended September 30, 2016 and 2015, respectively. At September 30, 2016, the Company had recorded $6.1 million of deferred revenue related to the Celgene collaboration, of which $1.8 million is estimated to be recognizable as revenue within one year.

Merck & Co., Inc.

In May 2015, the Company entered into a clinical research collaboration agreement with Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (“Merck”), to develop an assay intended to optimize immune-related gene expression signatures and evaluate the potential to predict benefit from Merck’s anti-PD-1therapy, KEYTRUDA. Under the terms of the collaboration agreement, the Company was eligible to receive up to $4.0 million, of which $2.0 million was received as an upfront payment in July 2015 and $1.9 million was received as development payments during 2015. In February 2016, the Company expanded its collaboration with Merck by entering into a new development collaboration agreement to clinically develop and commercialize a novel diagnostic test, based on an optimized gene expression signature, to predict response to KEYTRUDA in multiple tumor types. Under the terms of the new collaboration agreement, the Company received $12.0 million upfront as a technology access fee, will receive additional development funding, and is eligible to receive up to $12.0 million of near-term preclinical milestone payments, of which $8.5 million was achieved and received during the nine months ended September 30, 2016, and other potential downstream regulatory milestone payments.

The Company recognized collaboration revenue of $2.2 million and $6.1 million related to the Merck agreement for the three and nine months ended September 30, 2016, respectively, and $1.6 million and $1.8 million for the three and nine months ended September 30, 2015, respectively. As of September 30, 2016, the Company had recorded $22.4 million of deferred revenue related to the Merck collaboration, $7.7 million of which is estimated to be recognized as revenue within one year.

Medivation, Inc. and Astellas Pharma, Inc.

In January 2016, the Company entered into a collaboration agreement with Medivation, Inc. ("Medivation") and Astellas Pharma Inc. (“Astellas”) to pursue the translation of a novel gene expression signature algorithm discovered by Medivation into a companion diagnostic assay using the nCounter Analysis System. Under the terms of the collaboration agreement, the Company will modify its PAM50-based Prosigna Breast Cancer Assay for potential use as a companion diagnostic test for XTANDI (enzalutamide) for triple negative breast cancer. XTANDI is currently approved by the U.S. Food and Drug Administration for the treatment of metastatic castration-resistant prostate cancer.

The modified Prosigna test will be based upon data from a Phase 2 trial conducted by Medivation and Astellas that evaluated enzalutamide in patients with triple negative breast cancer. Under the terms of the collaboration agreement, the Company will be responsible for developing and validating the diagnostic test and, if the parties thereafter determine to proceed, will also be responsible for seeking regulatory approval for and commercializing the test. During 2016, the Company received $6.0 million upfront for technology access, $6.0 million in pre-clinical milestones, and is eligible to receive up to $10.0 million in development funding over the term of the agreement, in addition to other potential downstream milestone payments.

The Company recognized collaboration revenue of $1.5 million and $3.6 million related to the Medivation/Astellas agreement for the three and nine months ended September 30, 2016, respectively, and none for the three and nine months ended September 30, 2015. As of September 30, 2016, the Company had recorded $10.8 million of deferred revenue related to the Medivation/Astellas collaboration, $4.1 million of which is estimated to be recognized as revenue within one year.