LONG-TERM DEBT (Details) - Summary of interest expense incurred - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Cash Interest	$ 62,883	$ 62,673	$ 60,349
Amort. Debt Premium	122	270	270
Amort. Deferred Cost & Other Fees	3,539	5,123	4,949
Capitalized interest	128	385	549
Total Interest Expense	$ 66,544	$ 68,066	$ 65,568
Senior Notes Due 2028
Debt Instrument [Line Items]
Effective Interest Rate	5.90%
Cash Interest	$ 32,511
Amort. Debt Premium	0
Amort. Deferred Cost & Other Fees	1,072
Total Interest Expense	$ 33,583
Senior Notes Due 2022
Debt Instrument [Line Items]
Effective Interest Rate	5.67%	5.66%	5.66%
Cash Interest	$ 22,816	$ 52,500	$ 52,500
Amort. Debt Premium	122	270	270
Amort. Deferred Cost & Other Fees	1,735	3,803	3,803
Total Interest Expense	24,673	56,573	56,573
Revolver Due 2025
Debt Instrument [Line Items]
Cash Interest	5,866	6,998	3,718
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	635	980	565
Total Interest Expense	6,501	$ 7,978	$ 4,283
Real Estate Mortgages
Debt Instrument [Line Items]
Effective Interest Rate			6.30%
Cash Interest			$ 1,802
Amort. Debt Premium			0
Amort. Deferred Cost & Other Fees			124
Total Interest Expense			$ 1,926
ESOP Loans
Debt Instrument [Line Items]
Effective Interest Rate		6.30%	3.30%
Cash Interest		$ 937	$ 349
Amort. Debt Premium		0	0
Amort. Deferred Cost & Other Fees		186	320
Total Interest Expense		1,123	669
Finance Lease - Real Estate
Debt Instrument [Line Items]
Cash Interest	386
Amort. Debt Premium	0
Amort. Deferred Cost & Other Fees	25
Total Interest Expense	411
Finance Lease - Real Estate
Debt Instrument [Line Items]
Cash Interest		372	581
Amort. Debt Premium		0	0
Amort. Deferred Cost & Other Fees		25	25
Total Interest Expense		397	606
Non U.S. Lines of Credit
Debt Instrument [Line Items]
Cash Interest	12	19	34
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	15	15	15
Total Interest Expense	27	34	49
Non U.S. Term Loans
Debt Instrument [Line Items]
Cash Interest	975	1,592	1,420
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	55	109	90
Total Interest Expense	1,030	1,701	1,510
Other Long Term Debt
Debt Instrument [Line Items]
Cash Interest	445	640	494
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	2	5	7
Total Interest Expense	$ 447	$ 645	$ 501

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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