Regulatory Matters	6 Months Ended
Jun. 30, 2025
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Matters	Regulatory Assets and Liabilities. We follow the accounting and reporting requirements of ASC Topic 980, which provides that regulated entities account for and report assets and liabilities consistent with the economic effect of regulatory rate-making procedures when the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates will be charged and collected from customers. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income or expense are deferred on the balance sheet and are recognized in the income statement as the related amounts are included in customer rates and recovered from or refunded to customers. We assess the probability of collection for all of our regulatory assets each period. The offset to the regulatory liability associated with our renewable investments included in regulated rates is recorded in "Depreciation and amortization" on the Condensed Statements of Consolidated Income (unaudited). Renewable generation filings. In February 2025, NIPSCO filed a petition with the IURC to, after notice and hearing, issue an order modifying its February 13, 2023 order that approved a power purchase agreement related to Templeton and allow for NIPSCO to fully own Templeton. A final order is expected in October 2025. NIPSCO GenCo filing. In January 2025, NIPSCO GenCo, a subsidiary of NIPSCO Holdings II, filed a declination of jurisdiction petition with the IURC related to the ownership, development, financing, construction and operation of generation facilities. This is an administrative filing and is a step in NIPSCO’s effort to set up a framework to accommodate megaload customers, including data centers. A settlement agreement among GenCo, NIPSCO, and a coalition of NIPSCO's largest industrial customers has been reached and filed with the IURC. The evidentiary hearing was held on July 1, and an order is expected in the third quarter of 2025. NIPSCO Electric rate case filing. On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC. The IURC issued an Order on June 26, 2025, approving the Settlement Agreement without modification. New rates will be implemented in multiple steps beginning in July 2025 through the beginning of 2026.

Regulatory Assets and Liabilities. We follow the accounting and reporting requirements of ASC Topic 980, which provides that regulated entities account for and report assets and liabilities consistent with the economic effect of regulatory rate-making procedures when the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates will be charged and collected from customers. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income or expense are deferred on the balance sheet and are recognized in the income statement as the related amounts are included in customer rates and recovered from or refunded to customers. We assess the probability of collection for all of our regulatory assets each period. The offset to the regulatory liability associated with our renewable investments included in regulated rates is recorded in "Depreciation and amortization" on the Condensed Statements of Consolidated Income (unaudited).

Renewable generation filings. In February 2025, NIPSCO filed a petition with the IURC to, after notice and hearing, issue an order modifying its February 13, 2023 order that approved a power purchase agreement related to Templeton and allow for NIPSCO to fully own Templeton. A final order is expected in October 2025.

NIPSCO GenCo filing. In January 2025, NIPSCO GenCo, a subsidiary of NIPSCO Holdings II, filed a declination of jurisdiction petition with the IURC related to the ownership, development, financing, construction and operation of generation facilities. This is an administrative filing and is a step in NIPSCO’s effort to set up a framework to accommodate megaload customers, including data centers. A settlement agreement among GenCo, NIPSCO, and a coalition of NIPSCO's largest industrial customers has been reached and filed with the IURC. The evidentiary hearing was held on July 1, and an order is expected in the third quarter of 2025.

NIPSCO Electric rate case filing. On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC. The IURC issued an Order on June 26, 2025, approving the Settlement Agreement without modification. New rates will be implemented in multiple steps beginning in July 2025 through the beginning of 2026.