Industry Segment Information (Schedule of Segment Reporting Information Impacts on Statement of Operations, by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2023	May 31, 2022
Segment Reporting Information [Line Items]
Total operating revenues	$ 164,553	$ 214,259	$ 506,953	$ 580,547
Total operating income	26,957	35,162	78,820	66,861
Interest and other expense, net	(1,225)	394	(3,350)	(2,625)
Earnings before income taxes	25,732	35,556	75,470	64,236
Irrigation [Member]
Segment Reporting Information [Line Items]
Total operating revenues	142,571	188,693	442,430	515,360
Total operating income	30,727	39,567	92,188	81,513
Irrigation [Member] | North America [Member]
Segment Reporting Information [Line Items]
Total operating revenues	75,027	96,153	249,315	275,601
Irrigation [Member] | International [Member]
Segment Reporting Information [Line Items]
Total operating revenues	67,544	92,540	193,115	239,759
Infrastructure [Member]
Segment Reporting Information [Line Items]
Total operating revenues	21,982	25,566	64,523	65,187
Total operating income	3,556	3,779	8,947	6,869
Corporate Segment
Segment Reporting Information [Line Items]
Total operating income	$ (7,326)	$ (8,184)	$ (22,315)	$ (21,521)