Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net earnings	$ 18,260	$ 46,548
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	21,070	18,913
Loss (gain) due to settlements or curtailments of postretirement plan	(330)
Net (gain) loss on sales of assets	(58)	(3,699)
Stock-based compensation	12,423	1,261
Deferred income taxes	(11,681)	4,777
(Gain) loss on derivatives reclassified from accumulated comprehensive earnings into earnings	(18)	(18)
Changes in operating assets and liabilities:
Accounts receivable	72,714	87,615
Inventories	(28,796)	(37,632)
Accounts payable and accrued liabilities	(104,150)	(54,563)
Income taxes	25,597	(5,731)
Retirement benefit obligations	(673)	(897)
Other	(6,891)	(4,223)
Net cash (used in) provided by operating activities	(2,533)	52,351
Cash flows from investing activities:
Payments for purchase of property, plant and equipment	(28,450)	(21,058)
Proceeds from sale of assets	132	3,682
Proceeds from sales of short-term investments		758
Payments for purchases of short-term investments	(791)
Net cash used in investing activities	(29,109)	(16,618)
Cash flows from financing activities:
Cash dividends paid	(7,656)	(6,779)
Proceeds from sales of treasury stock	1,389	4,843
Payments for repurchases of common stock		(24,004)
Borrowings on revolving lines of credit and short-term borrowings	458,950	316,650
Payments on revolving lines of credit and short-term borrowings	(425,250)	(312,800)
Payments of long-term debt and capital lease obligations	(106)	(102)
Net cash (used in) provided by financing activities	27,327	(22,192)
Effect of exchange rate changes on cash and cash equivalents	2,542	(13,746)
Net change in cash and cash equivalents	(1,773)	(205)
Cash and cash equivalents at beginning of year	87,552	81,090
Cash and cash equivalents at end of period	$ 85,779	$ 80,885