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Cost of Sales Reduction, After Rebate

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Extended warranty term of revenue recognition.

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Organization Consolidation And Presentation Of Financial Statements [Line Items]

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Performance obligation amount recognized as a percentage of contract with customers liability of the previous period.

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Sale Of Energy, Percentage

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Standard Warranty Term Of Revenue Recognition

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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Summary of accounting policies - Revenue Recognition Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Sales energy yield management		2.00%	2.00%	0.00%
Contract with customer liability revenue recognized		$ 237,000,000.0	$ 203,300,000
Contract assets		533,257,000	405,890,000
Unbilled receivables current		$ 133,900,000	$ 140,400,000
Performance obligation amount recognized as a percentage of contract with customers liability of the previous period		69.00%	69.00%
Revenue, remaining performance obligation, amount		$ 410,000,000.0
Cost of sales reduction, after rebate	$ 121,400,000	$ (379,900,000)	$ (224,900,000)
Sales Channel, Bill And Hold
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Bill and hold arrangement, threshold portion of total project cost		5.00%
Contract with customer liability revenue recognized		$ 144,400,000
Revenue from contract with customer			$ 0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-04-01
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Revenue, remaining performance obligation, percentage		75.00%
Revenue, remaining performance obligation, expected timing of satisfaction, period		12 months
Minimum
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Extended warranty term of revenue recognition		10 years
Standard warranty term of revenue recognition		2 years
Maximum
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Extended warranty term of revenue recognition		15 years
Standard warranty term of revenue recognition		10 years