Quarterly report pursuant to Section 13 or 15(d)

Revenue and Accounts Receivable - Additional Information (Detail)

v3.7.0.1
Revenue and Accounts Receivable - Additional Information (Detail)
$ in Thousands
3 Months Ended
Mar. 31, 2017
USD ($)
company
Mar. 31, 2016
USD ($)
company
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Revenue $ 6,966 $ 6,068
Number of companies that accounted for approximately 10% or more of revenue | company 1 2
Payor | Testing Volume | Clinical Testing    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Percentage of benchmark 35.00% 35000.00%
Payor | Sales | Customer One | 10% or More Clinical Revenue    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Percentage of benchmark 11.00% 11.00%
Payor | Sales | Customer Two | 10% or More Clinical Revenue    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Percentage of benchmark   10.00%
Clinical Services    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Revenue $ 2,954 $ 2,456