XML 39 R29.htm IDEA: XBRL DOCUMENT v3.20.4
Revenue from Contracts with Customers (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Jan. 31, 2021
Jan. 31, 2020
Jan. 31, 2021
Jan. 31, 2020
Disaggregation of Revenue [Line Items]        
Description of timing     The majority of the Company's revenue arrangements are service contracts that are complete within a year or less. There are a few contracts that range in duration between 1 and 3 years.  
Oncology services revenue $ 10,812 $ 9,012 $ 30,476 $ 23,375
Pharmacology services        
Disaggregation of Revenue [Line Items]        
Oncology services revenue 10,745 8,843 30,199 22,732
Personalized oncology services        
Disaggregation of Revenue [Line Items]        
Oncology services revenue 5 169 155 581
Other        
Disaggregation of Revenue [Line Items]        
Oncology services revenue $ 62 $ 0 $ 122 $ 62