Ultimate trend rate for health care cost for defined benefit postretirement plan.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Recently Issued Accounting Standards - Additional Information (Detail) - USD ($) $ in Thousands	Apr. 30, 2020	Nov. 01, 2019	Aug. 31, 2018
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating right-of-use assets	$ 126,129
Operating lease liabilities	130,264
ASU 2016-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating right-of-use assets	126,129	$ 130,583
Operating lease liabilities	$ 130,264	$ 134,853
New Accounting Guidance Issued and Not Yet Adopted [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Defined benefit plan effect of percentage change in assumed health care cost trend rates			1.00%