Benefit Plans and Other Postretirement Benefits, Postretirement Benefit Plan Benefit Obligations, Cash Flows and Benefit Costs (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Funded Status of Plans at Dec. 31 [Abstract]
Noncurrent liabilities	$ (45,708,000)	$ (63,643,000)
Postretirement Benefit Plan
Change in Projected Benefit Obligation [Roll Forward]
Obligation at Jan. 1	19,432,000	22,127,000
Service cost	25,000	20,000	17,000
Interest cost	760,000	1,075,000	1,144,000
Medicare subsidy reimbursements	31,000	189,000
Plan amendments	0	(3,440,000)
Plan participants' contributions	621,000	893,000
Actuarial (gain) loss	(1,724,000)	1,486,000
Benefit payments	(1,992,000)	(2,918,000)
Obligation at Dec. 31	17,153,000	19,432,000	22,127,000
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at Jan. 1	647,000	746,000
Actual return (loss) on plan assets	(13,000)	3,000
Plan participants' contributions	621,000	893,000
Employer contributions	1,483,000	1,923,000
Benefit payments	(1,992,000)	(2,918,000)
Fair value of plan assets at Dec. 31	746,000	647,000	746,000
Funded Status of Plans at Dec. 31 [Abstract]
Funded status	(16,407,000)	(18,785,000)
Current liabilities	(718,000)	(943,000)
Noncurrent liabilities	(15,689,000)	(17,842,000)
Net postretirement amounts recognized on consolidated balance sheets	(16,407,000)	(18,785,000)
Amounts Not Yet Recognized as Components of Net Periodic Benefit Cost [Abstract]
Net loss	11,098,000	13,730,000
Prior service (credit) cost	(3,187,000)	(3,538,000)
Transition obligation	0	1,000
Total	7,911,000	10,193,000
Amounts Not Yet Recognized as Components of Net Periodic Benefit Cost Have Been Recorded as Follows Based Upon Expected Recovery in Rates [Abstract]
Current regulatory assets	570,000	433,000
Noncurrent regulatory assets	7,341,000	9,760,000
Total	7,911,000	10,193,000
Significant Assumptions Used to Measure Benefit Obligations [Abstract]
Measurement date	12/31/2013	12/31/2012
Discount rate for year-end valuation (in hundredths)	4.82%	4.10%
Mortality table	RP 2000	RP 2000
Health care costs trend rate - initial (in hundredths)	7.00%	7.50%
Ultimate health care trend assumption rate (in hundredths)	4.50%	4.50%
Period until ultimate trend rate is reached (in years)	5 years
Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
One-percent increase in APBO	1,773,000
One-percent decrease in APBO	(1,486,000)
One-percent increase in service and interest components	78,000
One-percent decrease in service and interest components	(61,000)
Cash Flows [Abstract]
Total contributions to Xcel Energy's postretirement health care plans during the year	1,500,000	1,900,000	2,400,000
Expected contribution to postretirement health care plans during 2014	1,500,000
Components of Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	25,000	20,000	17,000
Interest cost	760,000	1,075,000	1,144,000
Expected return on plan assets	(42,000)	(50,000)	(74,000)
Amortization of transition obligation	1,000	171,000	171,000
Amortization of prior service cost (credit)	(351,000)	(14,000)	(14,000)
Amortization of net loss	963,000	486,000	366,000
Net periodic benefit cost	1,356,000	1,688,000	1,610,000
Significant Assumptions Used to Measure Costs [Abstract]
Discount rate (in hundredths)	4.10%	5.00%	5.50%
Expected average long-term rate of return on assets (in hundredths)	7.11%	6.75%	7.50%
Xcel Energy Inc. | Postretirement Benefit Plan
Cash Flows [Abstract]
Total contributions to Xcel Energy's postretirement health care plans during the year	17,600,000	47,100,000	49,000,000
Expected contribution to postretirement health care plans during 2014	$ 13,300,000