Earnings per Share and Shareholders' Equity Share Repurchase (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended		165 Months Ended
	May 31, 2025	Feb. 28, 2025	Nov. 30, 2024	May 31, 2024	Feb. 29, 2024	Nov. 30, 2023	May 31, 2025	May 31, 2024	May 31, 2025	Aug. 31, 2024	Aug. 31, 2023
Equity [Abstract]
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	2,056,999						2,056,999		2,056,999
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 438,225	$ 405,978	$ 398,009	$ 365,771	$ 336,926	$ 321,676	$ 438,225	$ 365,771	$ 438,225	$ 391,979	$ 326,620
Net (loss) earnings	22,044	20,901	21,723	25,778	17,817	17,738	64,668	61,333
Other Comprehensive (Loss) Income, Net of Tax	20,517	(4,827)	(9,676)	708	(1,207)	370	6,014	$ (129)
Stock Issued During Period, Value, Employee Benefit Plan	117	97	91	75	35	51
Stock Issued During Period, Value, Restricted Stock Award, Gross		0	0	0	0	0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	3,340	2,841	3,345	2,772	2,810	2,717
Stock Value Issued to Acquired For and Distributed From Rabbi Trust	0	91	$ 0		263	90
Retained earnings	298,078						$ 298,078		298,078	$ 261,870
Treasury Stock, Value, Acquired, Cost Method	$ 14,040	$ 10,176		$ 2,583	$ 3,992	$ 26,116			$ 867,500
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	10,000,000						10,000,000		10,000,000
Treasury Stock, Common, Shares	0						0		0	0
Stock Repurchased During Period, Shares							660,050	1,165,767
Treasury Stock, Shares, Acquired									30,742,231
Stock Repurchased During Period, Value							$ 28,600	$ 32,700
Common Stock [Member]
Stock Issued During Period, Shares, New Issues	53,960,000	54,259,000	54,400,000	54,289,000	54,253,000	83,967,000	53,960,000	54,289,000	53,960,000	54,235,000	83,761,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 10,792	$ 10,852	$ 10,880	$ 10,858	$ 10,851	$ 16,793	$ 10,792	$ 10,858	$ 10,792	$ 10,847	$ 16,752
Stock Issued During Period, Shares, Employee Benefit Plan	5,000	2,000	2,000	2,000	1,000	2,000
Stock Issued During Period, Value, Employee Benefit Plan	$ 1			$ 1
Stock Issued During Period, Shares, Restricted Stock Award, Gross		73,000	186,000	14,000	105,000	118,000
Stock Issued During Period, Value, Restricted Stock Award, Gross		$ 14	$ 37	$ 2	$ 21	$ 23
Stock Issued To Acquired For And Distributed From Rabbi Trust	15,000	2,000			26,000	3,000
Stock Value Issued to Acquired For and Distributed From Rabbi Trust	$ 3	$ 1			$ 5	$ 1
Treasury Stock, Shares, Retired	330,000	220,000	110,000	72,000	29,867,000
Additional Paid-in Capital [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 239,739	$ 236,019	$ 233,964	$ 230,996	$ 226,075	223,474	239,739	230,996	239,739	235,660	220,472
Stock Issued During Period, Value, Employee Benefit Plan	116	97	91	74	35	51
Stock Issued During Period, Value, Restricted Stock Award, Gross		(14)	37	2	21	23
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	3,340	2,841	3,345	2,772	2,810	2,717
Stock Value Issued to Acquired For and Distributed From Rabbi Trust	(3)	90			258	89
Retained Earnings [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	298,078	290,008	279,239	245,256	222,047	1,028,871	298,078	245,256	298,078	261,870	1,011,112
Net (loss) earnings	22,044	20,901	21,723	25,778	17,817	17,738
AOCI Attributable to Parent [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(110,384)	(130,901)	(126,074)	(121,339)	(122,047)	(120,840)	(110,384)	(121,339)	(110,384)	(116,398)	(121,210)
Other Comprehensive (Loss) Income, Net of Tax	20,517	(4,827)	(9,676)	708	(1,207)	370
Stock held in trust [member] [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(3,576)	(3,575)	(3,774)	(3,777)	(3,777)	(3,576)	(3,576)	(3,777)	(3,576)	(3,777)	(3,484)
Stock Value Issued to Acquired For and Distributed From Rabbi Trust	1	(199)	3		(201)	(92)
Deferred Compensation, Share-based Payments [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	3,576	3,575	3,774	$ 3,777	3,777	3,576	$ 3,576	$ 3,777	$ 3,576	$ 3,777	$ 3,484
Stock Value Issued to Acquired For and Distributed From Rabbi Trust	$ 1	$ (199)	$ (3)		$ 201	$ 92