CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Revenue	$ 548,438	$ 510,522
Cost of goods and services	398,517	367,476
Gross profit	149,921	143,046
Selling, general and administrative expenses	117,798	113,754
Income from operations	32,123	29,292
Other income (expense)
Interest expense	(16,211)	(16,529)
Interest income	261	198
Other, net	778	1,004
Total other expense, net	(15,172)	(15,327)
Income before taxes	16,951	13,965
Provision from income taxes	6,339	5,212
Net income	$ 10,612	$ 8,753
Basic earnings per common share (in dollars per share)	$ 0.26	$ 0.21
Basic weighted-average shares outstanding (in shares)	41,173	40,750
Diluted earnings per common share (in dollars per share)	$ 0.24	$ 0.21
Diluted weighted-average shares outstanding (in shares)	43,895	41,888
Dividends paid per common share (in dollars per share)	$ 0.0750	$ 0.0725
Net income	$ 10,612	$ 8,753
Other comprehensive income (loss), net of taxes:
Foreign currency translation adjustments	6,470	(5,736)
Pension and other post retirement plans	672	184
Change in cash flow hedges	(301)	102
Total other comprehensive income (loss), net of taxes	6,841	(5,450)
Comprehensive income (loss), net	$ 17,453	$ 3,303