LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest	$ 15,906	$ 15,295	$ 31,204	$ 30,891
Amort. Debt Discount	(66)	(68)	(134)	(135)
Amort. Deferred Cost & Other Fees	(1,545)	(1,443)	(2,708)	(2,619)
Total Interest Expense	$ (17,517)	$ (16,806)	$ (34,046)	$ (33,645)
Senior notes due 2022 [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Effective Interest Rate	5.70%	5.70%	5.70%	5.70%
Cash Interest, including amounts capitalized	$ 13,125	$ 13,125	$ 26,250	$ 26,250
Amort. Debt Discount	(66)	(68)	(134)	(135)
Amort. Deferred Cost & Other Fees	(951)	(943)	(1,902)	(1,882)
Total Interest Expense	(14,142)	(14,136)	(28,286)	(28,267)
Revolver due 2021 [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, including amounts capitalized	1,631	922	2,564	2,278
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(400)	(140)	(541)	(281)
Total Interest Expense	(2,031)	(1,062)	(3,105)	(2,559)
Real estate mortgages [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, including amounts capitalized	0	166	0	351
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	0	(303)	0	(320)
Total Interest Expense	$ 0	$ (469)	$ 0	$ (671)
ESOP Loans [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Effective Interest Rate	7.20%	4.60%	6.60%	4.30%
Cash Interest, including amounts capitalized	$ 449	$ 442	$ 937	$ 855
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(155)	(31)	(186)	(62)
Total Interest Expense	$ (604)	$ (473)	$ (1,123)	$ (917)
Capital lease - real estate [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Effective Interest Rate	5.60%	5.50%	5.50%	10.70%
Cash Interest, including amounts capitalized	$ 101	$ 327	$ 216	$ 491
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(6)	(7)	(12)	(13)
Total Interest Expense	(107)	(334)	(228)	(504)
Non U.S. lines of credit [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, including amounts capitalized	4	4	11	11
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(4)	0	(8)	(7)
Total Interest Expense	(8)	(4)	(19)	(18)
Non U.S. term loans [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, including amounts capitalized	449	330	897	664
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(26)	(18)	(53)	(51)
Total Interest Expense	(475)	(348)	(950)	(715)
Other long term debt [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, including amounts capitalized	147	114	329	229
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	(3)	(1)	(6)	(3)
Total Interest Expense	(150)	(115)	(335)	(232)
Capitalized interest [Member]
LONG-TERM DEBT (Details) - Summary of Interest Expense Incurred [Line Items]
Cash Interest, Capitalized interest	0	(135)	0	(238)
Amort. Debt Discount	0	0	0	0
Amort. Deferred Cost & Other Fees	0	0	0	0
Total Interest Expense	$ 0	$ (135)	$ 0	$ (238)