Benefit Plans and Other Postretirement Benefits (Details) - Pension Plan [Member] - USD ($) $ in Millions |
1 Months Ended | 3 Months Ended | 9 Months Ended | ||||
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Jan. 31, 2026 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Components of Net Periodic Benefit Cost (Credit) [Abstract] | |||||||
| Service cost | $ 2 | $ 1 | $ 6 | $ 5 | |||
| Interest cost (a) | [1] | 7 | 5 | 18 | 17 | ||
| Expected return on plan assets (a) | [1] | (8) | (8) | (23) | (24) | ||
| Amortization of net loss (gain) (a) | [1] | 1 | 1 | 4 | 2 | ||
| Net periodic benefit cost (credit) | 2 | (1) | 5 | 0 | |||
| Contributions to pension plans | $ 2 | ||||||
| Defined Benefit Plan Credits Not Recognized Due To Effects of Regulation | 0 | 0 | 0 | 1 | |||
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | $ 2 | $ (1) | $ 5 | $ 1 | |||
| Xcel Energy Inc. | |||||||
| Components of Net Periodic Benefit Cost (Credit) [Abstract] | |||||||
| Contributions to pension plans | $ 75 | ||||||
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- Definition The additional amount of credits not recognized in net periodic benefit as reported in the financial statements of the entity due to effects of regulation. No definition available.
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- Definition The total mount of net periodic benefit cost, before regulatory adjustments, for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain or loss, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments, before regulatory adjustments. No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- Details
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