Segments - Reconciliation of Assets from Segment to Consolidated (Details) - USD ($) $ in Millions	Jun. 30, 2025	Sep. 30, 2024
Segment Reporting, Asset Reconciling Item [Line Items]
Goodwill and other intangible assets	$ 2,076.3	$ 2,116.9
Total assets	4,516.0	4,342.4
Operating Segments
Segment Reporting, Asset Reconciling Item [Line Items]
Tangible assets	2,001.0	1,773.8
Operating Segments \| Batteries & Lights
Segment Reporting, Asset Reconciling Item [Line Items]
Tangible assets	1,595.5	1,421.1
Operating Segments \| Auto Care
Segment Reporting, Asset Reconciling Item [Line Items]
Tangible assets	405.5	352.7
Corporate
Segment Reporting, Asset Reconciling Item [Line Items]
Tangible assets	$ 438.7	$ 451.7

Amount of asset recognized for present right to economic benefit.

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+ Details