Projected Benefit Payments (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
		Jan. 31, 2025	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
Defined Contribution Plan, Administrative Expense				$ 4	$ 4	$ 4
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation				393	383
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2026				31
2027				31
2028				32
2029				32
2030				33
2031-2035				161
Pension Plan [Member] | Xcel Energy [Member]
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
Payment for Pension Benefits		$ 75		125	100	50
Pension Plan [Member] | SPS [Member]
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
Payment for Pension Benefits		$ 2		3	3
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2026	[1]			3
2027	[1]			3
2028	[1]			3
2029	[1]			3
2030	[1]			3
2031-2035	[1]			11
Defined Benefit Plan, Overfunded Plan [Member] | Xcel Energy [Member]
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
Payment for Pension Benefits				$ 13	$ 11	$ 11
Defined Benefit Plan, Overfunded Plan [Member] | Xcel Energy [Member] | Subsequent Event
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
Payment for Pension Benefits			$ 8

[1] Amount is reported net of expected Medicare Part D subsidies, which are immaterial.