EBP, Employer Contribution, Annual Contribution, Percentage

No definition available.

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- Definition

EBP, Involuntary Cash-out Limit

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Account, Maximum Term For Repayment Deferral

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

EBP, Note Receivable From Participant, Maximum Number of Loans

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Number of Customers

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Number of States the Entity Operates In

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, After-Tax, Maximum Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Maximum Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Contribution, Pre-Tax, Catch-Up and Roth, Maximum Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	nix_
Data Type:	xbrli:pureItemType
Balance Type:	na
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- Definition

EBP, Rollover Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	nix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of contribution receivable from employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule II))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478642/962-310-45-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Description of the Plan (Details) - EBP 005 customer in Millions		5 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 22, 2020 loan	Dec. 31, 2025 USD ($) customer state loan	Dec. 31, 2024
EBP, Description of Plan [Line Items]
Number of customers \| customer			3.8
Number of states the entity operates in \| state			6
Maximum pre-tax, catch-up and Roth basis annual compensation to total compensation, percentage			0.50
Maximum after-tax annual compensation to total compensation, percentage			25.00%
Maximum annual compensation to total compensation, percentage			0.75
Discretionary contribution			$ 9,827,840
Annual Next Gen Employer Contribution, percentage			0.045
Automatic deferral rate			6.00%
Minimum borrowing, amount			$ 1,000
Maximum borrowing, amount			$ 50,000
Maximum borrowing, to total account, percentage			50.00%
Maximum number of loans \| loan		3	2
General loan, maximum borrowing term			5 years
Primary residence, maximum borrowing term	30 years		15 years
Maximum term for repayment deferral			1 year
Involuntary cash-out limit			$ 1,000
Rollover limit			$ 7,000
Minimum
EBP, Description of Plan [Line Items]
Participant loan, interest rate			3.25%	3.25%
Maximum
EBP, Description of Plan [Line Items]
Participant loan, interest rate			10.50%	10.50%
Non-Eligible Pension Plans
EBP, Description of Plan [Line Items]
Matching percentage			50.00%
Participant compensation matched, percentage			6.00%
Account Balance II
EBP, Description of Plan [Line Items]
Matching percentage			100.00%
Participant compensation matched, percentage			6.00%
Account Balance I
EBP, Description of Plan [Line Items]
Matching percentage			75.00%
Participant compensation matched, percentage			6.00%
NIPSCO Union Pension Plan
EBP, Description of Plan [Line Items]
Participant compensation matched, percentage			11.10%