Annual report pursuant to Section 13 and 15(d)

PENSION AND OTHER POSTRETIREMENT PLANS - Weighted Average Asset Allocation and Target Allocation (Details)

v3.19.3
PENSION AND OTHER POSTRETIREMENT PLANS - Weighted Average Asset Allocation and Target Allocation (Details) - USD ($)
$ in Thousands
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2017
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Fair value of plan assets $ 155,313 $ 158,662  
Pension      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Fair value of plan assets $ 155,313 158,662 $ 155,634
Defined Benefit Plan, Plan Assets, Allocations [Abstract]      
Target allocation of plan assets (as a percent) 100.00%    
Equity securities | Pension      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Fair value of plan assets $ 105,297 92,745  
Defined Benefit Plan, Plan Assets, Allocations [Abstract]      
Target allocation of plan assets (as a percent) 65.00%    
Fixed income, cash and cash equivalents | Pension      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Fair value of plan assets $ 39,156 44,250  
Defined Benefit Plan, Plan Assets, Allocations [Abstract]      
Target allocation of plan assets (as a percent) 25.00%    
Other investments | Pension      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Fair value of plan assets $ 10,860 $ 21,667  
Defined Benefit Plan, Plan Assets, Allocations [Abstract]      
Target allocation of plan assets (as a percent) 10.00%