Concentration of Risk and Segment Data (Segment Assets) (Details) - USD ($) $ in Thousands	May 31, 2021	Aug. 31, 2020
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 15,740,708	$ 14,397,416
Operating Segments | EMS
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	3,900,421	3,233,681
Operating Segments | DMS
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	7,261,735	6,641,764
Other non-allocated assets
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 4,578,552	$ 4,521,971