Benefit Plans (Notes)	12 Months Ended
Benefit Plans (Notes)	Dec. 31, 2023
Retirement Benefits [Abstract]
Employee Benefit Plans [Text Block]	Benefit Plans Certain of the benefit costs charged to us by Williams associated with employees who directly support us are described below. Additionally, allocated corporate expenses from Williams to us also include amounts related to these same employee benefits, which are not included in the amounts presented below (see Note 9 – Transactions With Major Customers and Affiliates). Pension and Other Postretirement Benefit Plans Williams has noncontributory defined benefit pension plans (Williams Pension Plan, Williams Inactive Employees Pension Plan, and The Williams Companies Retirement Restoration Plan) that provide pension benefits for its eligible employees hired prior to January 1, 2019. We received pension credits from Williams of $0.2 million in 2023, and pension charges of $0.7 million in 2022 and $0.8 million in 2021. Williams provides subsidized retiree medical benefits to a closed group of participants as well as retiree life insurance to eligible participants. During 2023, 2022, and 2021, we received credits from Williams related to retiree medical and life insurance benefits of $0.2 million, $1.2 million and $1.6 million, respectively. These credits were recorded as regulatory liabilities. We have been allowed by rate case settlements to collect or refund in future rates any differences between the actuarially determined costs and amounts currently being recovered in rates related to other postretirement benefits. Any differences between the annual actuarially determined cost and amounts currently being recovered in rates are recorded as regulatory assets or liabilities and collected or refunded through future rate adjustments. The amounts of other postretirement benefits costs deferred as regulatory liabilities at December 31, 2023 and 2022 are $42.4 million and $42.2 million, respectively. Defined Contribution Plan Williams maintains a defined contribution plan for substantially all of its employees. Williams charged us compensation expense of $3.0 million in 2023, $2.8 million in 2022 and $2.7 million in 2021 for Williams’ company contributions to this plan. Employee Stock-Based Compensation Plan Information The Williams Companies, Inc. 2007 Incentive Plan (the Plan), as subsequently amended and restated, provides for Williams’ common stock-based awards to both employees and non-management directors. The Plan permits the granting of various types of awards including, but not limited to, restricted stock units and stock options. Awards may be granted for no consideration other than prior and future services or based on certain financial performance targets achieved. Williams currently bills us directly for compensation expense related to stock-based compensation awards based on the fair value of the awards. We are also billed for our proportionate share of Williams’ and other affiliates’ stock-based compensation expense through various allocation processes. Total stock-based compensation expense for the years ended December 31, 2023, 2022 and 2021 was $1.5 million, $1.3 million and $1.2 million, respectively, excluding amounts allocated from Williams.

The entire disclosure for retirement benefits.

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