The percentage of expected requirements covered by the aggregate notional amount of derivative contracts expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract as a percentage of expected need.

No definition available.

Name:	us-gaap_DerivativeNonmonetaryNotionalAmountPercentOfRequiredNeedCoverage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Derivatives, Hedging Programs and Other Financial Instruments - Summary of Derivative Positions (Parenthetical) (Details) - Scenario, Forecast	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Electricity
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage					49.00%	58.00%	59.00%
Natural Gas
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage	25.00%	25.00%	85.00%	93.00%	95.00%	91.00%	83.00%