XML 59 R48.htm IDEA: XBRL DOCUMENT v3.24.1.u1

Gas in Storage (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Gas in Storage [Abstract]
LIFO Inventory Amount	$ 27.5	$ 0.0
Inventory [Line Items]
LIFO Inventory Amount	$ 27.5	$ 0.0

X

- Definition

Gas in Storage [Abstract]

+ References

No definition available.

+ Details

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Namespace Prefix:	nix_
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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration

X

- Definition

The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483489/210-10-50-1

+ Details

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