LONG-TERM DEBT (Details) - Summary of Long-Term Debt - USD ($) $ in Thousands	Mar. 31, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Outstanding Balance	$ 1,228,984	$ 1,134,692
less: Current portion, Outstanding Balance	(10,807)	(13,011)
Long-term debt, Outstanding Balance	1,218,177	1,121,681
Debt Instrument, Unamortized Premium	1,043	1,220
Debt Instrument, Unamortized Premium, Current	0	0
Debt Instrument, Unamortized Premium, Noncurrent	1,043	1,220
Capitalized Fees & Expenses	(13,025)	(14,830)
Long-term debt	1,217,002	1,121,082
less: Current portion	(10,807)	(13,011)
Long-term debt	1,206,195	1,108,071
Senior notes due 2022 [Member]
Debt Instrument [Line Items]
Outstanding Balance	1,000,000	1,000,000
Debt Instrument, Unamortized Premium	1,043	1,220
Capitalized Fees & Expenses	(11,066)	(12,968)
Long-term debt	$ 989,977	$ 988,252
Coupon Interest Rate	5.25%	5.25%
Revolver due 2021 [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 157,936	$ 25,000
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	(1,682)	(1,413)
Long-term debt	156,254	23,587
ESOP Loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	0	34,694
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	0	(186)
Long-term debt	0	34,508
Capital lease - real estate [Member]
Debt Instrument [Line Items]
Outstanding Balance	5,971	7,503
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	(68)	(80)
Long-term debt	$ 5,903	$ 7,423
Coupon Interest Rate	5.00%	5.00%
Non U.S. lines of credit [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 17,423	$ 7,951
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	(8)	(16)
Long-term debt	17,415	7,935
Non U.S. term loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	42,014	53,533
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	(182)	(148)
Long-term debt	41,832	53,385
Other long term debt [Member]
Debt Instrument [Line Items]
Outstanding Balance	5,640	6,011
Debt Instrument, Unamortized Premium	0	0
Capitalized Fees & Expenses	(19)	(19)
Long-term debt	$ 5,621	$ 5,992

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt premium.

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Amount of debt premium to be amortized within one year or the normal operating cycle, if longer.

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Amount of debt premium to be amortized after one year or the normal operating cycle, if longer.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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