CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 566,350	$ 549,633	$ 1,114,788	$ 1,060,155
Cost of goods and services	414,318	412,129	812,835	779,605
Gross profit	152,032	137,504	301,953	280,550
Selling, general and administrative expenses	126,467	111,783	244,265	225,537
Income from operations	25,565	25,721	57,688	55,013
Other income (expense)
Interest expense	(16,871)	(17,517)	(33,082)	(34,046)
Interest income	310	212	571	410
Loss from debt extinguishment, net	(6,690)	0	(6,690)	0
Other, net	615	1,268	1,393	2,272
Total other expense, net	(22,636)	(16,037)	(37,808)	(31,364)
Income before taxes from continuing operations	2,929	9,684	19,880	23,649
Provision from income taxes	2,034	3,194	8,373	8,406
Income from continuing operations	895	6,490	11,507	15,243
Discontinued operations:
Loss from operations of discontinued operations	0	(11,000)	0	(11,000)
Benefit for income taxes	0	(3,354)	0	(3,354)
Loss from discontinued operations	0	(7,646)	0	(7,646)
Net income (loss)	$ 895	$ (1,156)	$ 11,507	$ 7,597
Income (loss) from continuing operations (in dollars per share)	$ 0.02	$ 0.16	$ 0.28	$ 0.37
Income (loss) from discontinued operations (in dollars per share)	0	(0.19)	0	(0.19)
Basic earnings per common share (in dollars per share)	$ 0.02	$ (0.03)	$ 0.28	$ 0.19
Basic weighted-average shares outstanding (in shares)	41,565	40,949	41,369	40,849
Income from continuing operations (in dollars per share)	$ 0.02	$ 0.15	$ 0.26	$ 0.36
Income (loss) from discontinued operations (in dollars per share)	0	(0.18)	0	(0.18)
Diluted earnings per common share (in dollars per share)	$ 0.02	$ (0.03)	$ 0.26	$ 0.18
Diluted weighted-average shares outstanding (in shares)	43,734	42,832	43,826	42,376
Dividends paid per common share (in dollars per share)	$ 0.0750	$ 0.0725	$ 0.1500	$ 0.1450
Net income (loss)	$ 895	$ (1,156)	$ 11,507	$ 7,597
Other comprehensive income (loss), net of taxes:
Foreign currency translation adjustments	(16,471)	2,885	(10,001)	(2,851)
Pension and other post retirement plans	669	184	1,341	368
Change in cash flow hedges	968	(189)	667	(87)
Total other comprehensive income (loss), net of taxes	(14,834)	2,880	(7,993)	(2,570)
Comprehensive income (loss), net	$ (13,939)	$ 1,724	$ 3,514	$ 5,027