Derivative Instruments and Hedging Activities - Pro Forma Impact Of Offsetting Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivative Liability [Abstract]
Gross liability	$ (219.0)	$ (460.2)
Pro forma net presentation, liability, current	$ (78.3)	$ (172.9)
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration]	Derivative Liability Before Effects Of Master Netting Arrangements Current	Derivative Liability Before Effects Of Master Netting Arrangements Current
Pro forma net presentation, liability, noncurrent	$ (28.7)	$ (100.5)
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Derivative Liability Before Effects Of Master Netting Arrangements Noncurrent	Derivative Liability Before Effects Of Master Netting Arrangements Noncurrent
Pro forma net presentation, liability, total	$ (107.0)	$ (273.4)
Counterparties with Offsetting Positions or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(216.6)	(454.1)
Pro forma net presentation, liability, current	(75.9)	(169.5)
Pro forma net presentation, liability, noncurrent	(28.7)	(97.8)
Pro forma net presentation, liability, total	(104.6)	(267.3)
Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability		(6.1)
Pro forma net presentation, liability, current	(2.4)	(3.4)
Pro forma net presentation, liability, noncurrent	(2.4)	(2.7)
Pro forma net presentation, liability, total		(6.1)
Current Liabilities from Risk Management Activities [Member]
Derivative Liability [Abstract]
Gross liability	(156.6)	(320.1)
Current Liabilities from Risk Management Activities [Member] \| Counterparties with Offsetting Positions or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(154.2)	(316.7)
Current Liabilities from Risk Management Activities [Member] \| Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability	(2.4)	(3.4)
Long-Term Liabilities from Risk Management Activities [Member]
Derivative Liability [Abstract]
Gross liability	(62.4)	(140.1)
Long-Term Liabilities from Risk Management Activities [Member] \| Counterparties with Offsetting Positions or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(62.4)	(137.4)
Long-Term Liabilities from Risk Management Activities [Member] \| Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability	$ (2.4)	$ (2.7)

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Indicates line item in statement of financial position that includes derivative liability classified as current.

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Indicates line item in statement of financial position that includes derivative liability classified as noncurrent.

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