LONG-TERM DEBT (Details) - Summary of long-term debt - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Outstanding Balance	$ 1,064,422	$ 1,114,131
less: Current portion	(9,922)	(10,525)
Long-term debt	1,054,500	1,103,606
Original Issuer Premium	363	867
less: Current portion	0	0
Non-current	363	867
Capitalized fees & expenses	(17,821)	(10,724)
Capitalized Fees & Expenses, Current	0	0
Capitalized Fees & Expenses, Noncurrent	(17,821)	(10,724)
Balance Sheet	1,046,964	1,104,274
less: Current portion	(9,922)	(10,525)
Long-term debt	1,037,042	1,093,749
Senior Notes Due 2028
Debt Instrument [Line Items]
Outstanding Balance	1,000,000
Original Issuer Premium	363
Capitalized fees & expenses	(15,376)
Balance Sheet	$ 984,987
Coupon Interest Rate	5.75%
Senior Notes Due 2022
Debt Instrument [Line Items]
Outstanding Balance		1,000,000
Original Issuer Premium		867
Capitalized fees & expenses		(9,175)
Balance Sheet		$ 991,692
Coupon Interest Rate		5.25%
Revolver Due 2025
Debt Instrument [Line Items]
Outstanding Balance	$ 12,858
Original Issuer Premium	0
Capitalized fees & expenses	(2,209)
Balance Sheet	10,649
Revolver Due 2021
Debt Instrument [Line Items]
Outstanding Balance		$ 50,000
Original Issuer Premium		0
Capitalized fees & expenses		(1,243)
Balance Sheet		48,757
Finance Lease - Real Estate
Debt Instrument [Line Items]
Outstanding Balance	17,218
Original Issuer Premium	0
Capitalized fees & expenses	(30)
Balance Sheet	17,188
Finance Lease - Real Estate
Debt Instrument [Line Items]
Outstanding Balance		4,388
Original Issuer Premium		0
Capitalized fees & expenses		(55)
Balance Sheet		$ 4,333
Coupon Interest Rate		5.00%
Non U.S. Lines of Credit
Debt Instrument [Line Items]
Outstanding Balance	0	$ 17,576
Original Issuer Premium	0	0
Capitalized fees & expenses	(30)	(45)
Balance Sheet	(30)	17,531
Non U.S. Term Loans
Debt Instrument [Line Items]
Outstanding Balance	31,086	36,977
Original Issuer Premium	0	0
Capitalized fees & expenses	(160)	(188)
Balance Sheet	30,926	36,789
Other Long Term Debt
Debt Instrument [Line Items]
Outstanding Balance	3,260	5,190
Original Issuer Premium	0	0
Capitalized fees & expenses	(16)	(18)
Balance Sheet	$ 3,244	$ 5,172

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Amount of long term capitalized fees and expenses.

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The current portion of long term debt gross value.

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The carrying amount of long-term debt, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities).

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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