Condensed Statements of Income and Comprehensive Income (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income
Income (Loss) from Equity Method Investments		$ 36	$ 62	$ 40
Expenses and other deductions
Other income		13	(5)	6
Interest charges and financing costs		953	842	840
Income before income taxes		1,601	1,527	1,467
Income tax benefit		(135)	(70)	(6)
Net income		1,736	1,597	1,473
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Pension and retiree medical benefits, tax expense(benefit)		1	1	1
Derivative instruments, tax expense(benefit)		3	(1)	(7)
Total comprehensive income		$ 1,766	$ 1,615	$ 1,473
Weighted average common shares outstanding:
Basic		547	539	527
Diluted	[1]	547	540	528
Earnings per average common share:
Basic		$ 3.18	$ 2.96	$ 2.79
Diluted		$ 3.17	$ 2.96	$ 2.79
Xcel Energy Inc.
Income
Income (Loss) from Equity Method Investments		$ 1,905	$ 1,744	$ 1,646
Total income		1,905	1,744	1,646
Expenses and other deductions
Operating expenses		19	21	43
Other income		2	(3)	4
Interest charges and financing costs		206	173	198
Total expenses and other deductions		223	197	237
Income before income taxes		1,682	1,547	1,409
Income tax benefit		(54)	(50)	(64)
Net income		1,736	1,597	1,473
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net pension and retiree medical gains (losses) arising during the period, net of tax of $1, $— and $(2), respectively		9	8	5
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax		21	10	(5)
Other Comprehensive Income (Loss), Net of Tax		30	18	0
Total comprehensive income		$ 1,766	$ 1,615	$ 1,473

[1] Diluted common shares outstanding included common stock equivalents of 0.3 million, 0.3 million and 1.1 million shares for 2022, 2021 and 2020, respectively.