CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income	$ 31,530	$ 38,549
Adjustments to reconcile Net income to net cash provided by operating activities:
Depreciation and amortization	31,891	31,642
Impairment of assets	7,347	0
Share-based compensation expense	5,851	4,763
Deferred income tax expense (benefit)	(4,342)	1,434
Non-cash foreign exchange (gain)	(867)	(98)
Amortization of debt issuance costs	776	783
Accretion on Asset Retirement Obligations	146	106
(Gain) loss on disposal of assets	(65)	6
Other	(16)	1,803
Changes in operating assets and liabilities:
Accounts receivable	(3,989)	2,204
Inventories	4,023	(10,037)
Prepaid expenses and other assets	2,290	(2,455)
Accounts payable	1,190	(5,587)
Accrued expenses, income taxes payable and other liabilities	(21,727)	(14,989)
Net cash provided by operating activities	54,038	48,124
Cash flows from investing activities:
Additions to property, plant and equipment	(11,939)	(26,013)
Proceeds from the sale of assets	353	543
Net cash used in investing activities	(11,586)	(25,470)
Cash flows from financing activities:
Dividends paid	(13,260)	(12,487)
Repurchases of common stock under Share Repurchase Program	(9,201)	0
Repurchases of common stock withheld for taxes	(5,220)	(2,897)
Proceeds from issuance of stock	5,023	1,448
Repayment of long-term debt	(2,663)	(5,326)
Other financing activities	(43)	(2)
Net cash used in financing activities	(25,364)	(19,264)
Effect of exchange rate changes on cash	4,453	2,443
Increase in cash and cash equivalents	21,541	5,833
Cash and cash equivalents at beginning of period	257,354	188,495
Cash and cash equivalents at end of period	278,895	194,328
Supplemental Cash Flow Information:
Purchases of property, plant and equipment in accrued liabilities and accounts payable at the end of the period	3,645	9,043
Cash paid during the period for lease liabilities	1,997	1,897
Right of use asset obtained in exchange for lease liabilities	$ 454	$ 1,155