Benefit Plans and Other Postretirement Benefits, Pension Plan Benefit Obligations, Cash Flows and Benefit Costs (Details) $ in Millions		1 Months Ended		12 Months Ended
		Jan. 31, 2022 USD ($)		Dec. 31, 2022 USD ($)		Dec. 31, 2021 USD ($) Plan		Dec. 31, 2020 USD ($)		Dec. 31, 2019 USD ($)
Components of Net Periodic Benefit Cost (Credit) [Abstract]
Utilities Operating Expense, Maintenance, Operations, and Other Costs and Expenses						$ 831.0		$ 811.0		$ 810.0
Significant Assumptions Used to Measure Costs [Abstract]
Liability, Defined Benefit Plan, Noncurrent						23.0		161.0
Other Pension, Postretirement and Supplemental Plans [Member]
Change in Projected Benefit Obligation [Roll Forward]
Obligation at Jan. 1		$ 2.0		$ 2.0		2.0
Obligation at Dec. 31						2.0		2.0
Other Pension, Postretirement and Supplemental Plans [Member] | Xcel Energy Inc.
Change in Projected Benefit Obligation [Roll Forward]
Obligation at Jan. 1		43.0		43.0		43.0
Obligation at Dec. 31						43.0		43.0
Components of Net Periodic Benefit Cost (Credit) [Abstract]
Net benefit cost recognized for financial reporting						4.0		6.0
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation at Dec. 31						1,291.0		1,353.0
Change in Projected Benefit Obligation [Roll Forward]
Obligation at Jan. 1		1,363.0		1,363.0		1,428.0
Service cost						32.0		30.0		26.0
Interest cost						39.0		46.0		52.0
Plan amendments						0.0		0.0
Actuarial (gain) loss						(57.0)		102.0
Benefit payments						(79.0)		(80.0)
Obligation at Dec. 31						1,363.0		1,428.0
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at Jan. 1		1,351.0	[1]	$ 1,351.0	[1]	1,283.0	[2]
Actual return (loss) on plan assets						102.0		189.0
Employer contributions						45.0		50.0
Plan participants' contributions						0.0		0.0
Benefit payments						(79.0)		(80.0)
Fair value of plan assets at Dec. 31						1,351.0	[1]	1,283.0	[2]
Funded Status of Plans at Dec. 31 [Abstract]
Funded status						12.0		145.0
Amounts Not Yet Recognized as Components of Net Periodic Benefit Cost [Abstract]
Net loss						313.0		432.0
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax						(1.0)		(1.0)
Total						312.0		431.0
Amounts Not Yet Recognized as Components of Net Periodic Benefit Cost Have Been Recorded as Follows Based Upon Expected Recovery in Rates [Abstract]
Current regulatory assets						24.0		25.0
Noncurrent regulatory assets						288.0		404.0
Deferred income taxes						0.0		1.0
Net-of-tax accumulated OCI						0.0		1.0
Total						$ 312.0		$ 431.0
Significant Assumptions Used to Measure Benefit Obligations [Abstract]
Discount rate for year-end valuation (as a percent)						3.08%		2.71%
Expected average long-term increase in compensation level (as a percent)						3.75%		3.75%
Components of Net Periodic Benefit Cost (Credit) [Abstract]
Service cost						$ 32.0		$ 30.0		26.0
Interest cost						39.0		46.0		52.0
Expected return on plan assets						(73.0)		(70.0)		(69.0)
Amortization of prior service (credit) cost						0.0		(3.0)		(3.0)
Amortization of net loss						32.0		30.0		25.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	[3]					0.0		0.0		(3.0)
Net periodic pension cost						30.0		33.0		34.0
Defined Benefit Plan, Costs Not Recognized Due To Regulation						0.0		4.0		4.0
Net benefit cost recognized for financial reporting						$ 30.0		$ 37.0		$ 38.0
Significant Assumptions Used to Measure Costs [Abstract]
Discount rate (as a percent)						2.71%		3.49%		4.31%
Expected average long-term increase in compensation level (as a percent)						3.75%		3.75%		3.75%
Expected average long-term rate of return on assets (as a percent)						6.38%		6.84%		6.84%
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant						$ 0.0		$ 0.0
Medicare subsidy reimbursements						0.0		0.0
Liability, Defined Benefit Plan, Noncurrent						18.0		145.0
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position						(12.0)		(145.0)
Pension Plan [Member] | PSCo [Member]
Cash Flows [Abstract]
Total contributions to Xcel Energy's pension plans during the period						$ 46.0		$ 50.0		$ 46.0
Components of Net Periodic Benefit Cost (Credit) [Abstract]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement										$ (3.0)
Pension Plan [Member] | Xcel Energy Inc.
Cash Flows [Abstract]
Number of pension plans to which contributions were made | Plan						4
Pension Plan [Member] | Subsequent Event
Significant Assumptions Used to Measure Costs [Abstract]
Expected average long-term rate of return on assets for next fiscal year (as a percent)				6.39%
Pension Plan [Member] | Subsequent Event | PSCo [Member]
Cash Flows [Abstract]
Total contributions to Xcel Energy's pension plans during the period		$ 40.0

[1] See Note 8 for further information on fair value measurement inputs and methods.

[2] See Note 8 for further information on fair value measurement inputs and methods.

[3] A settlement charge is required when the amount of all lump-sum distributions during the year is greater than the sum of the service and interest cost components of the annual net periodic pension cost. In 2019, as a result of lump-sum distributions during the plan year, PSCo recorded a total pension settlement charge of $3 million. An immaterial amount was recorded in the income statement in 2019. There were no settlement charges recorded to the qualified pension plans in 2021 or 2020