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- Definition

Annualized fee received for retained CES obligation guarantees

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No definition available.

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- Definition

Contested amount of fines imposed by the Minnesota Office of Pipeline Safety.

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- Definition

Energy savings commitments not guaranteed

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- Definition

Number of sites identified where the entity may potentially have some remedial responsibility

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- Definition

Estimated Remaining Exposure

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Estimated Capital Expenditure to Clean Ash Ponds

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Exposure Period After Closing

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Exposure Period Until Increased Fee

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Number of Owned Coal Ash Ponds

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Represents the number of warranties the wholly owned subsidiary has outstanding in its role as general contractor.

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Represents the absolute number of surety bonds the wholly owned subsidiary has outstanding in its role as general contractor

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Percentage of work yet to be completed by wholly owned subsidiary on projects with open surety bonds.

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Performance Guarantees & Product Warranties [Abstract]

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Face amount of individual surety bonds the wholly-owned subsidiary has outstanding

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Quarterly increase of fee received for retained CES guarantee exposure

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Estimate of the reasonably possible loss exposure at an individual site.

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This represents the estimated years necessary to resolve the contingency.

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Solar Array Generating Capacity

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Warranty obligations outstanding face amount

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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Number of claims dismissed.

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Number of pending claims pertaining to a loss contingency.

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Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in remainder of current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment.

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- Definition

Term of the unrecognized unconditional purchase obligation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Commitments and Contingencies (Details)		1 Months Ended	3 Months Ended
Commitments and Contingencies (Details)	May 03, 2021 USD ($)	Dec. 31, 2018 lawsuit	Mar. 31, 2021 USD ($) ashPond suretyBond gasManufacturingAndStorageSite warrantyObligation MW	Apr. 29, 2021 lawsuit	Dec. 31, 2020 USD ($)	Aug. 31, 2018 lawsuit	Jul. 31, 2018 lawsuit
Performance Guarantees & Product Warranties [Abstract]
Number of surety bond obligations outstanding \| suretyBond			51
Performance guarantee obligations outstanding face amount			$ 527,000,000
Percentage of work yet to be completed on projects with open surety bonds			47.00%
Number of warranty obligations outstanding \| warrantyObligation			32
Warranty obligations outstanding face amount			$ 554,000,000
Energy savings commitments not guaranteed			1,200,000,000
Guarantor obligations, maximum exposure, undiscounted			$ 517,000,000
Legal, Environmental and Other Matters
Number of Owned Coal Ash Ponds \| ashPond			3
Energy Services Disposal Group [Member]
Legal, Environmental and Other Matters
Guarantor Obligations, Current Carrying Value			$ 0		$ 0
F.B. Culley
Legal, Environmental and Other Matters
Number of Owned Coal Ash Ponds \| ashPond			2
A.B. Brown
Legal, Environmental and Other Matters
Number of Owned Coal Ash Ponds \| ashPond			1
Posey Solar [Member]
Purchase Obligations
Solar Array Generating Capacity \| MW			300
Capital Addition Purchase Commitments
Purchase Obligations
Unrecorded Unconditional Purchase Obligation, Term			25 years
ESG
Legal, Environmental and Other Matters
Guarantees, Fair Value Disclosure			$ 0
Natural Gas and Coal
Purchase Obligations
Remaining nine months of 2021			429,000,000
2022			547,000,000
2023			470,000,000
2024			392,000,000
2025			337,000,000
2026			304,000,000
2027 and beyond			1,634,000,000
Technology Hardware and Software
Purchase Obligations
Remaining nine months of 2021			2,000,000
2022			12,000,000
2023			404,000,000
2024			198,000,000
2025			7,000,000
2026			7,000,000
2027 and beyond			137,000,000
Minnesota and Indiana Gas Service Territories [Member]
Legal, Environmental and Other Matters
Liability recorded for environmental loss contingencies			12,000,000
Minnesota and Indiana Gas Service Territories [Member] \| Minimum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites			$ 8,000,000
Years to resolve contingency			5
Minnesota and Indiana Gas Service Territories [Member] \| Maximum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites			$ 55,000,000
Years to resolve contingency			50
Indiana Gas Service Territory [Member]
Legal, Environmental and Other Matters
Environmental remediation number of sites with potential remedial responsibility \| gasManufacturingAndStorageSite			26
SIGECO [Member]
Legal, Environmental and Other Matters
Environmental remediation number of sites with potential remedial responsibility \| gasManufacturingAndStorageSite			5
CERC Corp [Member] \| Energy Services Disposal Group [Member]
Performance Guarantees & Product Warranties [Abstract]
Quarterly increase of fee received for retained CES guarantee exposure			3.00%
Quarterly increase of fee received for retained CES guarantee exposure			1.00%
Estimated Remaining Exposure			$ 51,000,000
Legal, Environmental and Other Matters
Additional Guarantees			$ 0
Exposure Period After Closing			90 days
Exposure Period Until Increased Fee			3 months
Guarantor Obligations, Current Carrying Value			$ 0		0
CERC Corp [Member] \| Subsequent Event [Member] \| Energy Services Disposal Group [Member]
Performance Guarantees & Product Warranties [Abstract]
Estimated Remaining Exposure	$ 41,000,000
CERC Corp [Member] \| Natural Gas
Purchase Obligations
Remaining nine months of 2021			271,000,000
2022			332,000,000
2023			279,000,000
2024			259,000,000
2025			231,000,000
2026			226,000,000
2027 and beyond			1,331,000,000
CERC Corp [Member] \| Minnesota Service Territory [Member]
Legal, Environmental and Other Matters
Liability recorded for environmental loss contingencies			7,000,000
CERC Corp [Member] \| Minnesota Service Territory [Member] \| Minimum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites			$ 5,000,000
Years to resolve contingency			30
CERC Corp [Member] \| Minnesota Service Territory [Member] \| Maximum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites			$ 32,000,000
Years to resolve contingency			50
Indiana Electric [Member]
Legal, Environmental and Other Matters
Asset retirement obligation			$ 88,000,000
Indiana Electric [Member] \| Minimum [Member]
Legal, Environmental and Other Matters
Estimated capital expenditure to clean ash ponds			60,000,000
Indiana Electric [Member] \| Maximum [Member]
Legal, Environmental and Other Matters
Estimated capital expenditure to clean ash ponds			80,000,000
Shell Energy North America (US), L.P.
Performance Guarantees & Product Warranties [Abstract]
Guarantor obligations, maximum exposure, undiscounted			$ 40,000,000
Minnehaha Academy Gas Explosion [Member]
Legal, Environmental and Other Matters
Contested amount of fines imposed					200,000
Minnehaha Academy Gas Explosion [Member] \| CERC Corp [Member]
Legal, Environmental and Other Matters
Contested amount of fines imposed					$ 200,000
February 2021 Winter Storm [Member] \| Subsequent Event [Member]
Legal, Environmental and Other Matters
Loss Contingency, Pending Claims, Number \| lawsuit				60
February 2021 Winter Storm [Member] \| Houston Electric [Member] \| Subsequent Event [Member]
Legal, Environmental and Other Matters
Loss Contingency, Pending Claims, Number \| lawsuit				60
Vectren Proxy Statement Materially Incomplete Related to Merger
Legal, Environmental and Other Matters
Loss Contingency, Pending Claims, Number \| lawsuit						7	7
Loss Contingency, Claims Dismissed, Number \| lawsuit		2