LONG-TERM DEBT (Details) - Summary of Long-Term Debt - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Debt Instrument [Line Items]
Outstanding Balance	$ 1,010,453	$ 952,856
less: Current portion, Outstanding Balance	(16,656)	(22,644)
Long-term debt, Outstanding Balance	993,797	930,212
Original Issuer Discount	(1,244)	(2,695)
less: Current portion, Original Issuer Discount	0	0
Long-term debt, Original Issuer Discount	(1,244)	(2,695)
Capitalized Fees & Expenses	(11,833)	(13,603)
Balance Sheet	997,376	936,558
less: Current portion	(16,656)	(22,644)
Long-term debt	980,720	913,914
Senior notes due 2022 [Member]
Debt Instrument [Line Items]
Outstanding Balance	725,000	725,000
Original Issuer Discount	(1,244)	(1,447)
Capitalized Fees & Expenses	(8,586)	(9,799)
Balance Sheet	$ 715,170	$ 713,754
Coupon Interest Rate	5.25%	5.25%
Revolver due 2019 [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 163,748	$ 0
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(2,040)	(2,425)
Balance Sheet	161,708	(2,425)
Convert. debt due 2017 [Member]
Debt Instrument [Line Items]
Outstanding Balance	0	100,000
Original Issuer Discount	0	(1,248)
Capitalized Fees & Expenses	0	(148)
Balance Sheet	0	$ 98,604
Coupon Interest Rate		4.00%
Real estate mortgages [Member]
Debt Instrument [Line Items]
Outstanding Balance	35,847	$ 37,861
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(499)	(595)
Balance Sheet	35,348	37,266
ESOP Loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	43,330	34,387
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(316)	(237)
Balance Sheet	43,014	34,150
Capital lease - real estate [Member]
Debt Instrument [Line Items]
Outstanding Balance	5,600	6,447
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(112)	(131)
Balance Sheet	$ 5,488	$ 6,316
Coupon Interest Rate	5.00%	5.00%
Non U.S. lines of credit [Member]
Debt Instrument [Line Items]
Outstanding Balance	$ 1,218	$ 11,462
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(35)	(1)
Balance Sheet	1,183	11,461
Non U.S. term loans [Member]
Debt Instrument [Line Items]
Outstanding Balance	31,461	33,669
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(224)	(247)
Balance Sheet	31,237	33,422
Other long term debt [Member]
Debt Instrument [Line Items]
Outstanding Balance	4,249	4,030
Original Issuer Discount	0	0
Capitalized Fees & Expenses	(21)	(20)
Balance Sheet	$ 4,228	$ 4,010