Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net earnings	$ 78,211	$ 109,883
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	61,331	65,556
Net (gain) on sales of assets and businesses	(1,541)	(1,942)
Stock-based compensation	13,957	16,438
Deferred income taxes	(55)	1,622
Changes in operating assets and liabilities:
Trade accounts receivable	(1,562)	(10,565)
Unbilled receivables (contract assets)	(48,742)	(32,565)
Costs to fulfill a contract	(10,884)	(9,226)
Inventories	(67,263)	16,877
Accounts payable and accrued liabilities	15,454	53,555
Contract liabilities	9,779	14,370
Income taxes	(725)	4,700
Retirement benefit obligations	(2,495)	(3,450)
Other	4,643	(6,256)
Net cash provided by operating activities	50,108	218,997
Cash flows from investing activities:
Payments for purchase of property, plant, and equipment	(24,150)	(13,313)
Proceeds from sale of assets	5	86
Payments for purchases of short-term investments	(8)	(2,750)
Proceeds from sales of short-term investments	11,305	16,566
Net cash (used in) provided by investing activities	(12,848)	589
Cash flows from financing activities:
Cash dividends paid	(22,134)	(15,404)
Proceeds from sales of treasury stock	19,399	28,454
Payments for repurchases of common stock	(273,535)
Borrowings on revolving lines of credit and short-term borrowings	11,500	74,400
Payments on revolving lines of credit and short-term borrowings	(11,500)	(74,400)
Payments of long-term debt and finance lease obligations	(564)	(100,835)
Net cash used in financing activities	(276,834)	(87,785)
Effect of exchange rate changes on cash and cash equivalents	(533)	2,524
Net change in cash and cash equivalents	(240,107)	134,325
Cash and cash equivalents, including restricted cash, at beginning of year	448,462	153,270
Cash and cash equivalents, including restricted cash, at end of period	$ 208,355	$ 287,595