Income Taxes - Tax Effects of Temporary Differences that give rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Aug. 31, 2018	Aug. 31, 2017
Deferred tax assets:
Accrued payroll and related liabilities	$ 18,461	$ 28,761
Deferred revenue	10,642	7,547
Inventories and other	10,518	13,641
Maintenance and warranty accruals	7,201	10,988
Net operating losses	2,002	320
Investment and asset tax credits	1,439	1,840
Deferred Tax Assets, Gross, Total	50,263	63,097
Deferred tax liabilities:
Fixed assets	70,942	110,429
Original issue discount	6,099	11,086
Intangibles	2,474	3,605
Other	1,831	(831)
Investment in GBW Joint Venture		14,066
Deferred Tax Liabilities, Gross, Total	81,346	138,355
Valuation allowance	657	533
Net deferred tax liability	$ 31,740	$ 75,791