Benefit Plans and Other Postretirement Benefits (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended			9 Months Ended
		Jan. 31, 2023	Sep. 30, 2023	Sep. 30, 2022		Sep. 30, 2023		Sep. 30, 2022
Pension Plan [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service Cost			$ 5	$ 6		$ 15		$ 20
Interest cost (a)	[1]		9	7		27		19
Expected return on plan assets (a)	[1]		(11)	(12)		(34)		(36)
Amortization of prior service credit (a)	[1]		0	0		0		0
Amortization of net loss (a)	[1]		3	6		9		18
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement			0	29	[2]	0	[2]	28	[2]
Net periodic benefit cost			6	36		17		49
Effects of regulation			8	(32)		13		(31)
Net benefit cost recognized for financial reporting			14	4		30		18
Total contributions to the pension plans during the period		$ 23
Pension Plan [Member] | Xcel Energy Inc.
Components of Net Periodic Benefit Cost [Abstract]
Total contributions to the pension plans during the period		$ 50
Other Postretirement Benefits Plan [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service Cost			0	0		0		0
Interest cost (a)	[1]		1	0		2		1
Expected return on plan assets (a)	[1]		0	0		0		0
Amortization of prior service credit (a)	[1]		0	(1)		0		(2)
Amortization of net loss (a)	[1]		0	1		0		1
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement			0	0		0	[2]	0	[2]
Net periodic benefit cost			1	0		2		0
Effects of regulation			0	0		0		0
Net benefit cost recognized for financial reporting			$ 1	$ 0		$ 2		$ 0

[1] The components of net periodic cost other than the service cost component are included in the line item “Other expense, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.

[2] In the third quarter of 2022, as a result of lump-sum distributions during the 2022 plan year, NSP-Minnesota recorded a pension settlement charge of $29 million, which was not recognized in earnings due to the effects of rate making.