Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	Apr. 30, 2021	Oct. 31, 2020
Disaggregation Of Revenue [Line Items]
Contract asset	$ 17.5	$ 16.9
Contract liability	44.2	$ 41.9
Service Agreements [Member]
Disaggregation Of Revenue [Line Items]
Remaining performance obligations	141.4
Licensing Agreements [Member]
Disaggregation Of Revenue [Line Items]
Remaining performance obligations	22.2
Advanced Technologies Contracts [Member]
Disaggregation Of Revenue [Line Items]
Remaining performance obligations	45.0
Posco Energy [Member]
Disaggregation Of Revenue [Line Items]
Deferred revenue	$ 22.2

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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