Long-term Contract for Purchase of Electric Power, Buyout Payment

No definition available.

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- Definition

Long-term Contract for Purchase of Electric Power, Contract Term Amendment

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No definition available.

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- Definition

Regulatory Matters [Line Items]

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No definition available.

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- Definition

Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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No definition available.

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Name:	us-gaap_PublicUtilitiesInterimRateIncreaseDecreaseAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

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No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Details

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Namespace Prefix:
Data Type:	na
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Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Mar. 31, 2019	Dec. 31, 2020
2020 Forward Test Period Retail Electric [Member] \| IPL [Member]
Regulatory Matters [Line Items]
Requested rate annual increase, amount		$ 204
Interim rate annual increase, amount		90
2020 Forward Test Period Retail Gas [Member] \| IPL [Member]
Regulatory Matters [Line Items]
Requested rate annual increase, amount		$ 21
Scenario, Forecast [Member] \| 2020 Forward Test Period Retail Electric [Member] \| IPL [Member]
Regulatory Matters [Line Items]
Requested rate annual increase, amount			$ 114
DAEC PPA [Member]
Regulatory Matters [Line Items]
PPA term amendment		5 years
Recovery period, authorized		5 years
DAEC PPA [Member] \| Scenario, Forecast [Member]
Regulatory Matters [Line Items]
Buyout payment	$ 110