Commitments and Contingencies - Additional Information (Details) $ in Millions			1 Months Ended	12 Months Ended
	Jun. 28, 2020 USD ($)	Apr. 27, 2020 USD ($)	Oct. 31, 2020 USD ($)	Oct. 31, 2021 USD ($) project MW	Dec. 20, 2021 USD ($)
Commitments And Contingencies [Line Items]
Recorded unconditional purchase obligation				$ 71.1
Loss contingency, damages sought			$ 880.0
Total number of projects | project				3
Accounts receivable outstanding				$ 11.2
Subsequent Event [Member] | POSCO Energy Settlement Agreement
Commitments And Contingencies [Line Items]
Contingent liability					$ 1.8
Tulare Biomart Project
Commitments And Contingencies [Line Items]
Term for procuring fuel				20 years
LIPA project
Commitments And Contingencies [Line Items]
Term for procuring fuel				7 years
CT-RFP 2 Derby 14.9 Mega Watt Project
Commitments And Contingencies [Line Items]
Under construction power plant capacity | MW				14.0
SCEF-Derby 208 Mega Watt Project
Commitments And Contingencies [Line Items]
Under construction power plant capacity | MW				2.8
Bridgeport
Commitments And Contingencies [Line Items]
Operating power plant capacity | MW				14.9
Hartford
Commitments And Contingencies [Line Items]
Operating power plant capacity | MW				7.4
Posco Energy [Member]
Commitments And Contingencies [Line Items]
Loss contingency, damages sought	$ 200.0	$ 3.3
Unspecified warranty claims		7.0
License termination		$ 110.0
Bond amount				$ 46.0