Number of customers that experienced an outage as a result of a severe weather event.

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- Definition

Nameplate Capacity

+ References

No definition available.

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- Definition

Number of Distribution Poles Replaced

+ References

No definition available.

+ Details

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- Definition

Number of Transmission Towers Replaced

+ References

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- Definition

Sections 205, 202 (c), and 309 Emergency order Cost Recovery

+ References

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- 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.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Regulatory Matters (Narrative) (Details) $ in Millions		9 Months Ended
Regulatory Matters (Narrative) (Details) $ in Millions	Aug. 11, 2026 segment	Sep. 30, 2026 USD ($) MW	Dec. 31, 2025 USD ($)
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 2,447.4	$ 2,225.2
Regulatory Liability, Noncurrent		1,633.4	$ 1,513.3
Number of Distribution Poles Replaced \| segment	1,500
Number of Transmission Towers Replaced \| segment	5
NIPSCO
Public Utilities, General Disclosures [Line Items]
Sections 205, 202 (c), and 309 Emergency order Cost Recovery		62.6
NIPSCO
Public Utilities, General Disclosures [Line Items]
Sections 205, 202 (c), and 309 Emergency order Cost Recovery		38.0
Emergency Order 202c
Public Utilities, General Disclosures [Line Items]
Regulatory Liability, Noncurrent		33.5
Emergency Order 202c
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 141.4
Rosewater
Public Utilities, General Disclosures [Line Items]
Nameplate Capacity \| MW		102
NIPSCO
Public Utilities, General Disclosures [Line Items]
Customers Impacted by Severe Weather Event \| segment	375,000