Derivative Instruments - Effect of Derivative Instruments on Statements of Income (Detail) - Cash Flow Hedging - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2023	May 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ (3.9)	$ 17.5	$ 18.2	$ 14.9
Gain (loss) reclassified from accumulated OCI into income	3.9	(2.2)	7.0	(5.2)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	0.7	0.5	1.9	1.4
Foreign Exchange Forward
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	$ 0.1	$ 0.2	(0.2)	$ (0.2)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest And Foreign Exchange Net	Interest And Foreign Exchange Net		Interest And Foreign Exchange Net
Foreign Exchange Forward | Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ 2.7	$ 1.5	4.7	$ (3.5)
Gain (loss) reclassified from accumulated OCI into income	(0.0)	(0.6)	(0.9)	(1.0)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	$ 0.6	$ 0.3	$ 1.4	$ 0.8
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax
Foreign Exchange Forward | Cost Of Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ 0.6	$ 0.8	$ 1.7	$ 0.9
Gain (loss) reclassified from accumulated OCI into income	0.5	0.1	1.1	0.1
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	$ 0.1	$ 0.2	$ 0.5	$ 0.6
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of Revenue	Cost of Revenue	Cost of Revenue	Cost of Revenue
Interest rate swap contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ (7.2)	$ 15.2	$ 11.8	$ 17.5
Gain (loss) reclassified from accumulated OCI into income	$ 3.4	$ (1.7)	$ 6.8	$ (4.3)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest And Foreign Exchange Net	Interest And Foreign Exchange Net	Interest And Foreign Exchange Net	Interest And Foreign Exchange Net