Revenue Recognition (Schedule of Disaggregation of Revenue by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Nov. 30, 2021	Nov. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	$ 161,363	$ 104,447
Lease revenue	4,789	4,038
Total operating revenues	166,152	108,485
Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	154,112	95,512
Over Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	7,251	8,935
Irrigation [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	145,909	87,356
Lease revenue	0	0
Total operating revenues	145,909	87,356
Irrigation [Member] | Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	139,400	80,060
Irrigation [Member] | Over Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	6,509	7,296
Infrastructure [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	15,454	17,091
Lease revenue	4,789	4,038
Total operating revenues	20,243	21,129
Infrastructure [Member] | Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	14,712	15,452
Infrastructure [Member] | Over Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers	$ 742	$ 1,639