Supplemental Statements of Cash Flows Information (Schedule of Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Supplemental Statements of Cash Flows Information
Interest paid, net of amounts capitalized	$ 11,302	$ 10,317
Income taxes paid	7,695	6,047
Income tax refunds received	1,772	59
Purchases of property, plant and equipment on account	10,631	6,130
Common shares issued from treasury stock to settle employee liabilities	$ 0	$ 1,767