AROs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022		Dec. 31, 2021
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	$ 3,151		$ 2,884
Amounts Incurred	59	[1]	107	[2]
Accretion	148		138
Cash flow revisions	22	[3]	22	[4]
Ending balance	3,380		3,151
Fair Value, Recurring [Member] | Estimate of Fair Value Measurement [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Decommissioning fund investments	2,882		3,256
Fair Value, Recurring [Member] | Nuclear Decommissioning Fund | Estimate of Fair Value Measurement [Member] | NSP Minnesota
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Decommissioning fund investments	2,900		3,300
Electric Plant Nuclear Production Decommissioning
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	2,056		1,957
Amounts Incurred	0	[1]	0	[2]
Accretion	104		99
Cash flow revisions	0	[3]	0	[4]
Ending balance	2,160		2,056
Electric Plant Wind Production
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	478		360
Amounts Incurred	25	[1]	101	[2]
Accretion	19		17
Cash flow revisions	(8)	[3]	0	[4]
Ending balance	514		478
Electric Plant Steam, Hydro and Other Production Asbestos
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	288		264
Amounts Incurred	34	[1]	6	[2]
Accretion	12		10
Cash flow revisions	14	[3]	8	[4]
Ending balance	348		288
Electric Plant Electric Distribution
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	47		46
Amounts Incurred	0	[1]	0	[2]
Accretion	1		1
Cash flow revisions	0	[3]	0	[4]
Ending balance	48		47
Natural Gas Plant Gas Transmission and Distribution
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	271		252
Amounts Incurred	0	[1]	0	[2]
Accretion	12		10
Cash flow revisions	23	[3]	9	[4]
Ending balance	306		271
Natural Gas Plant Miscellaneous
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	8		3
Amounts Incurred	0	[1]	0	[2]
Accretion	0		0
Cash flow revisions	(7)	[3]	5	[4]
Ending balance	1		8
Common and Other Property Common Miscellaneous
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	1		1
Amounts Incurred	0	[1]	0	[2]
Accretion	0		0
Cash flow revisions	0	[3]	0	[4]
Ending balance	1		1
Non utility and other
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	2		1
Amounts Incurred	0	[1]	0	[2]
Accretion	0		1
Cash flow revisions	0	[3]	0	[4]
Ending balance	$ 2		$ 2

[1] Amounts incurred related to the wind farms placed in service in 2022 for NSP-Minnesota (Dakota Range and Rock Aetna) and steam production pond remediation costs for PSCo.

[2] Amounts incurred related to the wind farms placed in service in 2021 for NSP-Minnesota (Blazing Star 2, Mower and Freeborn) and removal of a utility scale battery asset in NSP-Minnesota.

[3] In 2022, AROs were revised for changes in timing and estimates of cash flows. Revisions in steam, hydro and other production AROs were primarily related to changes in cost estimates for remediation of ash containment facilities. Changes in gas transmission and distribution AROs were primarily related to changes in labor rates coupled with increased gas line mileage and number of services.

[4] In 2021, AROs were revised for changes in timing and estimates of cash flows. Revisions in steam, hydro and other production AROs were primarily related to changes in cost estimates for remediation of ash containment facilities. Changes in gas transmission and distribution AROs were primarily related to changes in labor rates coupled with increased gas line mileage and number of services.