Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Operating activities
Net income	$ 139,051	$ 136,645	$ 84,639
Adjustments to reconcile net income to net cash provided by operating activities
Gain on sale of a business	0	(27,575)	(5,093)
Depreciation and amortization	72,347	66,890	54,727
Amortization of debt issuance costs and original issue discount	1,804	1,542	1,446
Deferred income taxes	(796)	(9,008)	938
Loss on extinguishment of debt	0	0	9,805
Provision for losses on accounts receivable and inventory	4,656	7,241	1,333
Stock-based compensation expense	11,798	14,664	12,788
Gain on purchase of business	(7,384)	0	0
Other adjustments to net income	(1,938)	2,023	896
Changes in operating assets and liabilities, net of effects from acquisitions
Accounts receivable	6,026	(44,419)	(13,445)
Inventories	9,002	(36,528)	(10,301)
Prepaid expenses and other current assets	(3,054)	(1,762)	(3,074)
Accounts payable	(21,981)	31,667	8,673
Income taxes	4,511	(3,179)	(9,138)
Accrued and other liabilities	(2,782)	7,243	(11,232)
Other, net	(1,566)	259	(1,308)
Net cash provided by operating activities	209,694	145,703	121,654
Investing activities
Capital expenditures	(34,860)	(38,501)	(25,122)
Proceeds from sale of properties, plant and equipment	80	349	100
Proceeds from divestiture of business	0	42,631	0
Proceeds from sale of assets held for sale	0	0	3,024
Acquisitions of businesses, net of cash acquired	(97,999)	(3,467)	(183,923)
Other, net	(322)	1,502	88
Net cash (used for) provided by investing activities	(133,101)	2,514	(205,833)
Financing activities
Borrowings under credit facility	39,000	358,000	97,000
Repayments under credit facility	(39,000)	(443,000)	(12,000)
Repayments of short-term debt	(20,980)	(8,150)	(4,200)
Issuance of long-term debt	0	426,217	498,750
Repayments of long-term debt	(40,000)	(1,217)	(641,100)
Issuance of common stock	7,374	20,110	12,168
Repurchase of common stock	(24,419)	(411,775)	(13,938)
Payments for debt financing costs and fees	0	(5,955)	(4,375)
Other, net	(155)	(161)	(65)
Net cash used for financing activities	(78,180)	(65,931)	(67,760)
Effects of foreign exchange rate changes on cash and cash equivalents	(1,660)	(1,342)	(2,622)
Increase (decrease) in cash and cash equivalents	(3,247)	80,944	(154,561)
Cash and cash equivalents at beginning of period	126,662	45,718	200,279
Cash and cash equivalents at end of period	123,415	126,662	45,718
Supplementary Cash Flow information
Interest paid	49,879	39,898	26,131
Income taxes paid, net of refunds	38,698	41,601	49,813
Capital expenditures, not yet paid	$ 3,719	$ 916	$ 1,330