Leases (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2023		Sep. 30, 2022		Sep. 30, 2023		Sep. 30, 2022		Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Finance Lease, Right-of-Use Asset, Amortization		$ 1		$ 1		$ 2		$ 3
Finance Lease, Interest Expense		4		4		12		12
Finance Lease, Cost		5		5		14		15
Operating Lease, Cost		72	[1]	67	[1]	217	[2]	210	[2]
Lessee, Operating Lease, Liability, to be Paid		1,401				1,401
Finance Lease, Liability, Payment, Due	[3]	220				220
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(240)				(240)
Finance Lease, Liability, Undiscounted Excess Amount	[3]	(156)				(156)
Operating Lease, Liability		1,161				1,161
Finance Lease, Liability	[3]	64				64
Operating Lease, Liability, Current		(231)				(231)				$ (217)
Finance Lease, Liability, Current	[3]	(2)				(2)
Operating lease liabilities		930				930				$ 1,038
Finance Lease, Liability, Noncurrent	[3]	62				62
Short-term Lease, Cost		$ 1		1		$ 6		4
WYCO, Inc.
Lessee, Lease, Description [Line Items]
Equity Method Investment, Ownership Percentage		50.00%				50.00%
PPAs
Lessee, Lease, Description [Line Items]
Operating Lease, Cost		$ 61		59		$ 182		182
Lessee, Operating Lease, Liability, to be Paid		1,108				1,108
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(139)				(139)
Operating Lease, Liability		969				969
Property, Plant and Equipment, Other Types
Lessee, Lease, Description [Line Items]
Operating Lease, Cost		11	[4]	$ 8	[4]	35	[5]	$ 28	[5]
Lessee, Operating Lease, Liability, to be Paid		293				293
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(101)				(101)
Operating Lease, Liability		$ 192				$ 192

[1] PPA capacity payments are included in electric fuel and purchased power on the consolidated statements of income. Expense for other operating leases is included in O&M expense and electric fuel and purchased power.

[2] PPA capacity payments are included in electric fuel and purchased power on the consolidated statements of income. Expense for other operating leases is included in O&M expense and electric fuel and purchased power.

[3] Excludes certain amounts related to Xcel Energy’s 50% ownership interest in WYCO.

[4] Includes short-term lease expense of $1 million for both 2023 and 2022.

[5] Includes short-term lease expense of $6 million and $4 million for 2023 and 2022, respectively.