Quarterly report pursuant to Section 13 or 15(d)

Revenue and Accounts Receivable - Additional Information (Details)

v3.7.0.1
Revenue and Accounts Receivable - Additional Information (Details)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
USD ($)
company
Jun. 30, 2016
USD ($)
company
Jun. 30, 2017
USD ($)
company
Jun. 30, 2016
USD ($)
company
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Revenue | $ $ 6,604 $ 7,001 $ 13,570 $ 13,069
Payor | Testing Volume | Clinical Testing        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Percentage of benchmark 45.00% 40.00% 39.00% 38.00%
Payor | Sales | 10% or More Clinical Revenue        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Percentage of benchmark 12.00%   11.00%  
Number of companies that accounted for approximately 10% or more of revenue | company 1 2 1 2
Payor | Sales | Customer One | 10% or More Clinical Revenue        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Percentage of benchmark   15.00%   13.00%
Payor | Sales | Customer Two | 10% or More Clinical Revenue        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Percentage of benchmark   11.00%   11.00%