Derivative Instruments (Details) $ in Millions		3 Months Ended
	Mar. 31, 2022 USD ($) MWh	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Other Current Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value of outstanding swap agreements	$ 4.2	$ 4.2	$ 6.2
Other Noncurrent Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value of outstanding swap agreements	$ 0.2	0.2
Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of outstanding swap agreements | MWh	156,800
Settlement of derivative contract		$ 2.8