LONG-TERM DEBT (Details) - Summary of Long-Term Debt - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017
Debt Instrument [Line Items]
Outstanding Balance	$ 1,267,789	$ 992,401
Debt Instrument, Unamortized Premium	1,484
less: Current portion, Outstanding Balance	(12,593)	(11,078)
Debt Instrument, Unamortized Premium, Current	0
Long-term debt, Outstanding Balance	1,255,196	981,323
Debt Instrument, Unamortized Premium, Noncurrent	1,484
Original Issuer Discount		(1,177)
less: Current portion, Original Issuer Discount		0
Long-term debt, Original Issuer Discount		(1,177)
Capitalized Fees & Expenses	(18,287)	(12,066)
Long-term debt	1,250,986	979,158
less: Current portion	(12,593)	(11,078)
Long-term debt	1,238,393	968,080
Senior notes due 2022 [Member]
Debt Instrument [Line Items]
Outstanding Balance	1,000,000	725,000
Debt Instrument, Unamortized Premium	1,484
Original Issuer Discount		(1,177)
Capitalized Fees & Expenses	(15,619)	(9,220)
Long-term debt	$ 985,865	$ 714,603
Coupon Interest Rate	5.25%	5.25%
Revolver due 2021 [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 147,743	$ 144,216
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(1,830)	(1,951)
Long-term debt	145,913	142,265
Real estate mortgages [Member]
Debt Instrument [Line Items]
Outstanding Balance	23,047	23,642
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(304)	(320)
Long-term debt	22,743	23,322
ESOP Loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	42,106	42,675
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(279)	(310)
Long-term debt	41,827	42,365
Capital lease - real estate [Member]
Debt Instrument [Line Items]
Outstanding Balance	9,705	5,312
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(99)	(105)
Long-term debt	$ 9,606	$ 5,207
Coupon Interest Rate	5.00%	5.00%
Non U.S. lines of credit [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 4,675	$ 9,402
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(27)	(31)
Long-term debt	4,648	9,371
Non U.S. term loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	34,765	35,943
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(108)	(108)
Long-term debt	34,657	35,835
Other long term debt [Member]
Debt Instrument [Line Items]
Outstanding Balance	5,748	6,211
Debt Instrument, Unamortized Premium	0
Original Issuer Discount		0
Capitalized Fees & Expenses	(21)	(21)
Long-term debt	$ 5,727	$ 6,190

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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Amount, after accumulated amortization, of debt discount.

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

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

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Amount, after accumulated amortization, of debt premium.

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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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