Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total stockholders equity	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Total Accumulated Other Comprehensive (Loss) Earnings [Member]	Foreign Currency Translation Adjustments [Member]	Unrealized Derivative Gains (Losses) [Member]	Minimum Retirement Benefit Liability Adjustments [Member]	Deferred Compensation in Equity [Member]	Retained Earnings [Member]	Treasury Stock at Cost [Member]	Treasury Stock Held for Deferred Compensaton [Member]	Total
Balances at Sep. 30, 2014	$ 1,160,944		$ 106	$ 112,491	$ (3,533)	$ 10,819	$ 105	$ (14,457)	$ 3,915	$ 1,338,468	$ (286,588)	$ (3,915)
Balance, Common Stock, shares at Sep. 30, 2014			72,960,000
Balance, Treasury Stock, shares at Sep. 30, 2014											(7,397,000)
Balance, Treasury stock held for deferred compensation, Shares at Sep. 30, 2014												(198,000)
Net earnings	181,452	$ 0	$ 0	0	0	0	0	0	0	181,452	$ 0	$ 0	$ 181,452
Other comprehensive income (loss), net of tax	(47,925)	0	0	0	(47,925)	(32,429)	61	(15,557)	0	0	0	0
Cash dividends paid	(24,646)	$ 0	0	0	0	0	0	0	0	(24,646)	0	0
Purchases of treasury stock	(160,294)										$ (160,294)
Purchases of treasury stock, shares											(3,193,000)
Sales of treasury stock	9,932			(6,817)							$ 16,749
Sales of treasury stock, shares											568,000
Common shares issued from treasury stock to settle employee liabilities													0
Common shares issued from treasury stock for benefit plans	12,574			4,490							$ 8,084		$ 12,574
Common shares issued from treasury stock for benefit plans, shares											259,000		259,000
Tax benefit attributable to stock-based compensation	6,812			6,812
Stock-based compensation	14,255			14,255
Purchases of stock by deferred compensation plan									893			$ (893)
Purchases of stock by deferred compensation plan, shares												(18,000)
Distribution of stock from deferred compensation plan									(486)			$ 486
Distribution of stock from deferred compensation plan, shares												43,000
Balances at Sep. 30, 2015	1,153,104		$ 106	131,231	(51,458)	(21,610)	166	(30,014)	4,322	1,495,274	$ (422,049)	$ (4,322)
Balance, Common Stock, shares at Sep. 30, 2015			72,960,000
Balance, Treasury Stock, shares at Sep. 30, 2015											(9,763,000)
Balance, Treasury stock held for deferred compensation, Shares at Sep. 30, 2015												(173,000)
Net earnings	180,838									180,838			$ 180,838
Other comprehensive income (loss), net of tax	(14,247)				(14,247)	(4,361)	13	(9,899)
Cash dividends paid	(26,606)									(26,606)
Purchases of treasury stock	(126,295)										$ (126,295)
Purchases of treasury stock, shares											(2,660,000)
Sales of treasury stock	16,645			(10,137)							$ 26,782
Sales of treasury stock, shares											732,000
Common shares issued from treasury stock to settle employee liabilities													0
Common shares issued from treasury stock for benefit plans	13,999			5,319							$ 8,680		$ 13,999
Common shares issued from treasury stock for benefit plans, shares											317,000		317,000
Tax benefit attributable to stock-based compensation	35			35
Stock-based compensation	15,122			15,122
Purchases of stock by deferred compensation plan									1,269			$ (1,269)
Purchases of stock by deferred compensation plan, shares												(25,000)
Distribution of stock from deferred compensation plan									(502)			$ 502
Distribution of stock from deferred compensation plan, shares												41,000
Balances at Sep. 30, 2016	1,212,595		$ 106	141,570	(65,705)	(25,971)	179	(39,913)	5,089	1,649,506	$ (512,882)	$ (5,089)	$ 1,212,595
Balance, Preferred Stock, shares at Sep. 30, 2016		0											0
Balance, Common Stock, shares at Sep. 30, 2016			72,960,000										72,960,000
Balance, Treasury Stock, shares at Sep. 30, 2016											(11,374,000)		(11,374,000)
Balance, Treasury stock held for deferred compensation, Shares at Sep. 30, 2016												(157,000)	(157,000)
Net earnings	200,507									200,507			$ 200,507
Other comprehensive income (loss), net of tax	12,519				12,519	(1,309)	(44)	13,872
Cash dividends paid	(29,745)									(29,745)
Purchases of treasury stock	(73,224)										$ (73,224)
Purchases of treasury stock, shares											(1,056,000)
Sales of treasury stock	15,668			(2,257)							$ 17,925
Sales of treasury stock, shares											466,000
Common shares issued from treasury stock to settle employee liabilities	1,767			740					1,767		$ 1,027	$ (1,767)	1,767
Common shares issued from treasury stock to settle employee liabilities, shares											26,000	(26,000)
Common shares issued from treasury stock for benefit plans	14,014			6,501							$ 7,513		$ 14,014
Common shares issued from treasury stock for benefit plans, shares											199,000		199,000
Stock-based compensation	17,282			17,282
Purchases of stock by deferred compensation plan									298			$ (298)
Purchases of stock by deferred compensation plan, shares												(3,000)
Distribution of stock from deferred compensation plan									(19)			$ 19
Balances at Sep. 30, 2017	$ 1,371,383		$ 106	$ 163,836	$ (53,186)	$ (27,280)	$ 135	$ (26,041)	$ 7,135	$ 1,820,268	$ (559,641)	$ (7,135)	$ 1,371,383
Balance, Preferred Stock, shares at Sep. 30, 2017		0											0
Balance, Common Stock, shares at Sep. 30, 2017			72,960,000										72,960,000
Balance, Treasury Stock, shares at Sep. 30, 2017											(11,739,000)		(11,739,000)
Balance, Treasury stock held for deferred compensation, Shares at Sep. 30, 2017												(186,000)	(186,000)