Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	May 31, 2020	May 31, 2020	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017	Sep. 01, 2019
Leases [Abstract]
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation			$ 20,600	$ 18,900
Operating Leases, Rent Expense, Net			113,300	88,500	$ 81,300
Cumulative Effect of New Accounting Principle in Period of Adoption						$ 33,700
Finance Lease, Liability, Payments, Remainder of Fiscal Year	$ 1,689	$ 1,689
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	17,401	17,401
Capital Leases, Future Minimum Payments Due, Next Twelve Months			6,761
Operating Leases, Future Minimum Payments Due, Next Twelve Months			87,168
Operating Lease, Payments		45,718
Operating Lease, Right-of-Use Asset	261,125	261,125				268,400
Operating Lease, Expense	17,057	53,155
Finance Lease, Right-of-Use Asset, Amortization	1,908	5,170
Finance Lease, Interest Expense	257	742
Short-term Lease, Cost	3,108	12,768
Variable Lease, Cost	1,176	2,089
Lease, Cost	23,506	73,924
Operating Lease, Liability	263,769	263,769				$ 267,000
Finance Lease, Right-of-Use Asset	42,854	42,854
Finance Lease, Liability, Current	6,710	6,710
Operating Lease, Liability, Current	57,470	57,470
Finance Lease, Liability, Noncurrent	22,443	22,443
Finance Lease, Liability	$ 29,153	$ 29,153
Operating Lease, Weighted Average Remaining Lease Term	8 years 6 months	8 years 6 months
Finance Lease, Weighted Average Remaining Lease Term	6 years 2 months	6 years 2 months
Operating Lease, Weighted Average Discount Rate, Percent	3.13%	3.13%
Finance Lease, Weighted Average Discount Rate, Percent	3.31%	3.31%
Finance Lease, Interest Payment on Liability		$ 742
Finance Lease, Principal Payments		5,239
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability		32,567
Capital Leases, Future Minimum Payments Due in Two Years			6,199
Operating Leases, Future Minimum Payments, Due in Two Years			57,381
Capital Leases, Future Minimum Payments Due in Three Years			5,021
Operating Leases, Future Minimum Payments, Due in Three Years			43,665
Capital Leases, Future Minimum Payments Due in Four Years			4,548
Operating Leases, Future Minimum Payments, Due in Four Years			34,328
Capital Leases, Future Minimum Payments Due in Five Years			2,638
Operating Leases, Future Minimum Payments, Due in Five Years			26,793
Capital Leases, Future Minimum Payments Due Thereafter			6,517
Operating Leases, Future Minimum Payments, Due Thereafter			92,653
Capital Leases, Future Minimum Payments, Net Minimum Payments			31,684
Operating Leases, Future Minimum Payments Due			341,988
Capital Leases, Future Minimum Payments, Interest Included in Payments			3,445
Capital Lease Obligations			28,239
Finance Lease, Liability, Payments, Due Next Twelve Months	$ 7,297	7,297
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	61,134	61,134
Finance Lease, Liability, Payments, Due Year Two	6,141	6,141
Lessee, Operating Lease, Liability, Payments, Due Year Two	47,348	47,348
Finance Lease, Liability, Payments, Due Year Three	5,472	5,472
Lessee, Operating Lease, Liability, Payments, Due Year Three	37,260	37,260
Finance Lease, Liability, Payments, Due Year Four	3,067	3,067
Lessee, Operating Lease, Liability, Payments, Due Year Four	29,368	29,368
Finance Lease, Liability, Payments, Due Year Five	9,339	9,339
Lessee, Operating Lease, Liability, Payments, Due Year Five	174,940	174,940
Finance Lease, Liability, Payment, Due	33,005	33,005
Lessee, Operating Lease, Liability, Payments, Due	367,451	367,451
Finance Lease, Liability, Undiscounted Excess Amount	3,852	3,852
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	103,682	103,682
Operating Lease, Liability, Noncurrent	$ 206,299	206,299
Capital Leased Assets, Gross			$ 62,700	$ 50,000
Right of use asset modification		$ 6,507