Leases (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2024		Jun. 30, 2023		Jun. 30, 2024		Jun. 30, 2023		Dec. 31, 2023
Lessee, Lease, Description [Line Items]
Finance Lease, Right-of-Use Asset, Amortization		$ 1		$ 0		$ 2		$ 1
Finance Lease, Interest Expense		3		4		7		8
Finance Lease, Cost		4		4		9		9
Operating Lease, Cost		68	[1]	73	[1]	137	[2]	145	[2]
Lessee, Operating Lease, Liability, to be Paid		1,467				1,467
Finance Lease, Liability, Payment, Due	[3]	213				213
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(280)				(280)
Finance Lease, Liability, Undiscounted Excess Amount	[3]	(150)				(150)
Operating Lease, Liability		1,187				1,187
Finance Lease, Liability	[3]	63				63
Operating Lease, Liability, Current		(226)				(226)				$ (226)
Finance Lease, Liability, Current	[3]	(2)				(2)
Operating lease liabilities		961				961				$ 1,038
Finance Lease, Liability, Noncurrent	[3]	61				61
Short-term Lease, Cost		$ 1		3		$ 2		5
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		$ 57		61		$ 115		121
Lessee, Operating Lease, Liability, to be Paid		1,107				1,107
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(135)				(135)
Operating Lease, Liability		972				972
Property, Plant and Equipment, Other Types
Lessee, Lease, Description [Line Items]
Operating Lease, Cost		11	[4]	$ 12	[4]	22	[5]	$ 24	[5]
Lessee, Operating Lease, Liability, to be Paid		360				360
Lessee, Operating Lease, Liability, Undiscounted Excess Amount		(145)				(145)
Operating Lease, Liability		$ 215				$ 215

[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 and $3 million for 2024 and 2023, respectively.

[5] Includes short-term lease expense of $2 million and $5 million for 2024 and 2023, respectively.