Leases (Narrative) (Details)	12 Months Ended
	Aug. 31, 2017
Leases [Line Items]
Lease expiration date	Mar. 31, 2032
Lease renewal options, initial term period	5 years
Company Drive Ins [Member]
Leases [Line Items]
Lease expiration date	May 31, 2037
Direct Financing Leases [Member]
Leases [Line Items]
Lease expiration date	Sep. 30, 2031