Leases, Balance Sheet Components (Details) - USD ($) $ in Thousands	Aug. 31, 2021	Aug. 31, 2020
Assets:
Operating assets	$ 112,202	$ 114,905
Finance assets	55,308	50,642
Total leased assets	167,510	165,547
Operating lease liabilities:
Current	26,433	27,604
Long-term	93,409	95,810
Total operating lease liabilities	119,842	123,414
Finance lease liabilities:
Current	16,040	14,373
Long-term	36,104	35,851
Total finance lease liabilities	52,144	50,224
Total lease liabilities	$ 171,986	$ 173,638
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and other payables	Accrued expenses and other payables
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Long-term Debt, Current Maturities	Long-term Debt, Current Maturities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term debt	Long-term debt