CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details) - Summary of Condensed Consolidating Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 13,595	$ (1,156)	$ 8,753	$ 5,827	$ 90,280	$ 30,989	$ 21,192	$ 127,096
Net (income) loss from discontinued operations	533			1,615			8,179	(94,872)
Net cash provided by (used in) operating activities							14,982	(5,463)
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(10,376)			(11,520)			(27,794)	(33,148)
Acquired businesses, net of cash acquired							(9,219)	(429,545)
Investment purchase							(149)	0
Proceeds (payments) related to sale of business							(9,500)	473,977
Insurance proceeds (payments)							(10,604)	8,254
Proceeds from sale of assets							104	482
Net cash provided by (used in) investing activities - continuing operations							(57,162)	20,020
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Purchase of shares for treasury							(1,478)	(45,588)
Proceeds from long-term debt							156,800	419,645
Payments of long-term debt							(108,260)	(262,031)
Financing costs							(1,012)	(7,671)
Contingent consideration for acquired businesses							(1,686)	0
Dividends paid							(10,262)	(46,816)
Other, net							(197)	139
Net cash provided by financing activities - continuing operations							33,905	57,678
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in discontinued operations							(3,874)	(62,273)
Effect of exchange rate changes on cash and equivalents							503	6,123
NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS							(11,646)	16,085
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD			69,758			47,681	69,758	47,681
CASH AND EQUIVALENTS AT END OF PERIOD	58,112			63,766			58,112	63,766
Parent Company [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	13,595			5,827			21,192	127,096
Net (income) loss from discontinued operations	0			0			0	0
Net cash provided by (used in) operating activities							(20,805)	300,739
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment							(247)	(455)
Acquired businesses, net of cash acquired							(9,219)	(368,937)
Investment purchase							(149)
Proceeds (payments) related to sale of business							(9,500)	0
Insurance proceeds (payments)							(10,604)	8,254
Proceeds from sale of assets							0	0
Net cash provided by (used in) investing activities - continuing operations							(29,719)	(361,138)
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Purchase of shares for treasury							(1,478)	(45,588)
Proceeds from long-term debt							138,541	411,718
Payments of long-term debt							(75,694)	(223,998)
Financing costs							(1,012)	(7,671)
Contingent consideration for acquired businesses							0
Dividends paid							(10,262)	(46,816)
Other, net							(197)	(21,897)
Net cash provided by financing activities - continuing operations							49,898	65,748
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in discontinued operations							0	0
Effect of exchange rate changes on cash and equivalents							0	0
NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS							(626)	5,349
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD			15,976			3,240	15,976	3,240
CASH AND EQUIVALENTS AT END OF PERIOD	15,350			8,589			15,350	8,589
Guarantor Companies [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	15,697			(9,055)			54,400	55,125
Net (income) loss from discontinued operations	0			1,615			0	(77,172)
Net cash provided by (used in) operating activities							24,179	(536,544)
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment							(23,221)	(27,229)
Acquired businesses, net of cash acquired							0	(4,490)
Investment purchase							0
Proceeds (payments) related to sale of business							0	473,977
Insurance proceeds (payments)							0	0
Proceeds from sale of assets							79	46
Net cash provided by (used in) investing activities - continuing operations							(23,142)	442,304
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Purchase of shares for treasury							0	0
Proceeds from long-term debt							116	2,232
Payments of long-term debt							(2,605)	(4,564)
Financing costs							0	0
Contingent consideration for acquired businesses							0
Dividends paid							0	0
Other, net							5,694	(20,205)
Net cash provided by financing activities - continuing operations							3,205	(22,537)
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in discontinued operations							0	127,312
Effect of exchange rate changes on cash and equivalents							(118)	(131)
NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS							4,124	10,404
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD			16,353			8,066	16,353	8,066
CASH AND EQUIVALENTS AT END OF PERIOD	20,477			18,470			20,477	18,470
Non-Guarantor Companies [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	16,330			(4,487)			40,829	54,709
Net (income) loss from discontinued operations	533			0			8,179	(17,700)
Net cash provided by (used in) operating activities							11,608	230,342
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment							(4,326)	(5,464)
Acquired businesses, net of cash acquired							0	(56,118)
Investment purchase							0
Proceeds (payments) related to sale of business							0	0
Insurance proceeds (payments)							0	0
Proceeds from sale of assets							25	436
Net cash provided by (used in) investing activities - continuing operations							(4,301)	(61,146)
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Purchase of shares for treasury							0	0
Proceeds from long-term debt							18,143	5,695
Payments of long-term debt							(29,961)	(33,469)
Financing costs							0	0
Contingent consideration for acquired businesses							(1,686)
Dividends paid							0	0
Other, net							(5,694)	42,241
Net cash provided by financing activities - continuing operations							(19,198)	14,467
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in discontinued operations							(3,874)	(189,585)
Effect of exchange rate changes on cash and equivalents							621	6,254
NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS							(15,144)	332
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD			37,429			36,375	37,429	36,375
CASH AND EQUIVALENTS AT END OF PERIOD	22,285			36,707			22,285	36,707
Elimination [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	(32,027)			13,542			(95,229)	(109,834)
Net (income) loss from discontinued operations	0			0			0	0
Net cash provided by (used in) operating activities							0	0
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment							0	0
Acquired businesses, net of cash acquired							0	0
Investment purchase							0
Proceeds (payments) related to sale of business							0	0
Insurance proceeds (payments)							0	0
Proceeds from sale of assets							0	0
Net cash provided by (used in) investing activities - continuing operations							0	0
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Purchase of shares for treasury							0	0
Proceeds from long-term debt							0	0
Payments of long-term debt							0	0
Financing costs							0	0
Contingent consideration for acquired businesses							0
Dividends paid							0	0
Other, net							0	0
Net cash provided by financing activities - continuing operations							0	0
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in discontinued operations							0	0
Effect of exchange rate changes on cash and equivalents							0	0
NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS							0	0
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD			$ 0			$ 0	0	0
CASH AND EQUIVALENTS AT END OF PERIOD	$ 0			$ 0			$ 0	$ 0