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Commitments Commitments 2 (Details) - Electric Power Purchase Commitments [Member] - Electric:	12 Months Ended
	Dec. 31, 2019
Minimum
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Derivative, Term of Contract	3 years
Maximum [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Derivative, Term of Contract	5 years

X

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Details

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X

- Details

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X

- Details

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X

- Details

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