Variable Interest Entities - World Energy (Details) $ in Millions	1 Months Ended	3 Months Ended
	Nov. 30, 2023 renewal	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)
Variable Interest Entity [Line Items]
Financing receivables		$ 965.3	$ 1,220.2
World Energy | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Financing receivables			$ 300.0
Term of project agreement (in years)	15 years
Number of renewal terms of project agreement | renewal	2
Project agreement, renewal term (in years)	5 years
Project exit costs		1,800.0
Impairment of property and equipment		1,400.0
Provision for credit loss		$ 300.0