Amount of direct financing lease revenue.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Revenue Recognition (Schedule of Disaggregation of Revenue by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2019	May 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									$ 436,320
Lease revenue									7,752
Operating revenues	$ 101,885	$ 121,054	$ 109,182	$ 111,951	$ 123,269	$ 169,571	$ 130,339	$ 124,526	444,072	$ 547,705	$ 517,985
Irrigation [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									351,498
Lease revenue									0
Operating revenues									351,498	439,858	418,041
Infrastructure [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									84,822
Lease revenue									7,752
Operating revenues									92,574	$ 107,847	$ 99,944
Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									397,312
Point in Time [Member] \| Irrigation [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									318,544
Point in Time [Member] \| Infrastructure [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									78,768
Over Time [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									39,008
Over Time [Member] \| Irrigation [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									32,954
Over Time [Member] \| Infrastructure [Member]
Disaggregation Of Revenue [Line Items]
Revenue from the contracts with customers									$ 6,054