ACQUISITIONS (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 29, 2016	Oct. 16, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Business Acquisition [Line Items]
Goodwill			$ 305,704		$ 305,704		$ 291,157
Business Combination, Contingent Consideration, Liability	$ 2,700
Revenue, Net			$ 140,191	$ 134,191	$ 411,954	$ 383,679
Fremont Plastics, Inc [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 10,500
Goodwill		4,400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total		3,600
Business Acquisition Purchase Price Allocation Real Property		$ 2,000
Plastique Group Limited [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	31,600
Goodwill	10,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total	11,900
Revenue, Net	35,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total	$ 9,600