Segment Reporting - Schedule of Income Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
May 31, 2025	May 31, 2024	May 31, 2025	May 31, 2024
Segment Reporting Information [Line Items]
Operating profit	$ 139.8	$ 145.3	$ 383.3	$ 396.3
Interest expense (income), net	12.1	(1.8)	15.0	(1.0)
Miscellaneous expense (income), net	2.3	(0.5)	5.8	1.2
Income before income taxes	125.4	147.6	362.5	396.1
Operating Segments \| Acuity Brands Lighting
Segment Reporting Information [Line Items]
Operating profit	134.0	151.5	407.6	421.3
Operating Segments \| Acuity Intelligent Spaces
Segment Reporting Information [Line Items]
Operating profit	27.4	12.5	48.1	26.9
Unallocated corporate amounts
Segment Reporting Information [Line Items]
Operating profit	$ (21.6)	$ (18.7)	$ (72.4)	$ (51.9)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

+ Details