The amount of cash inflow from sale of investment tax credit.

No definition available.

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Represents the term of hydrogen production and power purchase agreement.

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No definition available.

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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 noncurrent.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer, classified as noncurrent.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2023	Apr. 30, 2026	Oct. 31, 2025
Revenue Recognition
Contract asset		$ 153.5	$ 131.1
Contract asset, long-term		109.9	82.1
Contract liability		14.7	8.7
Toyota Investment Tax Credit Sale
Revenue Recognition
Consideration payable	$ 6.3	6.0	6.0
Consideration payable, long term	6.0	5.1	$ 4.5
Sale of investment tax credit	$ 6.3
Hydrogen production and power purchase agreement	20 years
Generation
Revenue Recognition
Remaining performance obligations		$ 370.3
Generation \| Minimum
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		19 years
Generation \| Maximum
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		20 years
Advanced Technologies
Revenue Recognition
Remaining performance obligations		$ 4.9
Advanced Technologies \| Maximum
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		2 years
Product
Revenue Recognition
Remaining performance obligations		$ 36.1
Product \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-11-01
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		2 years
Service Agreements \| Service
Revenue Recognition
Remaining performance obligations		$ 155.4
Service Agreements \| Service \| Minimum
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		3 years
Service Agreements \| Service \| Maximum
Revenue Recognition
Revenue performance obligation expected timing of satisfaction		15 years