Quarterly report pursuant to Section 13 or 15(d)

Significant Accounting Policies - Revenue by Major Customers (Detail)

v3.20.2
Significant Accounting Policies - Revenue by Major Customers (Detail) - Revenues - Customer Concentration Risk
 3 Months Ended 9 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Private        
Concentration Risk [Line Items]        
Concentration risk percentage 30.90% 29.10% 36.10% 30.40%
Public        
Concentration Risk [Line Items]        
Concentration risk percentage 69.10% 70.90% 63.90% 69.60%