Leases (Notes)
 9 Months Ended
May 31, 2021
Leases [Abstract]  
Leases of Lessee Disclosure [Text Block] Leases
    We assess arrangements at inception to determine whether they contain a lease. An arrangement is considered to contain a lease if it conveys the right to control the use of an asset for a period of time in exchange for consideration. The right to control the use of an asset must include both (a) the right to obtain substantially all economic benefits associated with an identified asset and (b) the right to direct how and for what purpose the identified asset is used. Certain arrangements provide us with the right to use an identified asset; however, most of these arrangements are not considered to represent a lease, as we do not control how and for what purpose the identified asset is used. For example, our supply agreements, warehousing and distribution services agreements, and transportation services agreements generally do not contain leases.

    We lease property, plant and equipment used in our operations primarily under operating lease agreements and, to a lesser extent, under finance lease agreements. Our operating leases are primarily for railcars, equipment, vehicles and office space, many of which contain renewal options and escalation clauses. Renewal options are included as part of the right of use asset and liability when it is reasonably certain that we will exercise the renewal option; however, renewal options are generally not included as we are not reasonably certain to exercise such options.

    Operating lease right of use assets and liabilities for operating leases are recognized at the lease commencement date for leases in excess of 12 months based on the present value of lease payments over the lease term. For measurement and classification of lease agreements, lease and nonlease components are grouped into a single lease component for all asset classes. Variable lease payments are excluded from measurement of right of use assets and liabilities and generally include payments for nonlease components such as maintenance costs, payments for leased assets beyond their noncancelable lease term and payments for other nonlease components such as sales tax. The discount rate used to calculate present value is our
collateralized incremental borrowing rate or, if available, the rate implicit in the lease. The incremental borrowing rate is determined for each lease based primarily on its lease term. Certain lease arrangements include rental payments adjusted annually based on changes in an inflation index. Our lease arrangements generally do not contain residual value guarantees or material restrictive covenants.

    Lease expense is recognized on a straight-line basis over the lease term. The components of lease expense recognized in our Condensed Consolidated Statements of Operations are as follows:
Three Months Ended May 31,Nine Months Ended May 31,
2021202020212020
(Dollars in thousands)
Operating lease expense$18,534 $17,057 $54,508 $53,155 
Finance lease expense:
Amortization of assets
1,974 1,908 5,919 5,170 
Interest on lease liabilities
218 257 694 742 
Short-term lease expense3,970 3,108 12,394 12,768 
Variable lease expense668 1,176 2,209 2,089 
Total net lease expense*
$25,364 $23,506 $75,724 $73,924 
*Income related to sub-lease activity is not material and has been excluded from the table above.

    Supplemental balance sheet information related to operating and finance leases is as follows:
Balance Sheet LocationMay 31,
2021		August 31,
2020
(Dollars in thousands)
Operating leases
Assets
Operating lease right of use assets
Other assets$262,737 $257,834 
Liabilities
Current operating lease liabilities
Accrued expenses58,767 57,200 
Long-term operating lease liabilities
Other liabilities207,513 203,691 
Total operating lease liabilities
$266,280 $260,891 
Finance leases
Assets
Finance lease assets
Property, plant and equipment$39,393 $44,860 
Liabilities
Current finance lease liabilities
Current portion of long-term debt7,152 7,993 
Long-term finance lease liabilities
Long-term debt19,307 23,467 
Total finance lease liabilities
$26,459 $31,460 
Weighted average remaining lease term (in years)
Operating leases
7.98.3
Finance leases
5.76.0
Weighted average discount rate
Operating leases
2.99 %3.11 %
Finance leases
3.34 %3.33 %

    
Supplemental cash flow and other information related to operating and finance leases are as follows:
Nine Months Ended May 31,
20212020
(Dollars in thousands)
Cash paid for amounts included in measurement of lease liabilities:
Operating cash flows from operating leases
$56,448 $45,718 
Operating cash flows from finance leases
694 742 
Financing cash flows from finance leases
6,426 5,239 
Supplemental noncash information:
Right of use assets obtained in exchange for lease liabilities
37,284 32,567 
Right of use asset modifications
23,886 6,507 

    Maturities of lease liabilities as of May 31, 2021, were as follows:
May 31, 2021
Finance LeasesOperating Leases
(Dollars in thousands)
Remainder of fiscal 2021$2,004 $18,002 
Fiscal 20227,787 65,469 
Fiscal 20236,206 51,946 
Fiscal 20243,487 41,945 
Fiscal 20252,078 31,211 
After fiscal 20258,071 108,601 
Total maturities of lease liabilities
29,633 317,174 
Less amounts representing interest3,174 50,894 
Present value of future minimum lease payments
26,459 266,280 
Less current lease liabilities7,152 58,767 
Long-term lease liabilities$19,307 $207,513