Fair Value of Financial Assets and Liabilities (Details) (USD $)	3 Months Ended
	Mar. 31, 2012 Y		Mar. 31, 2011		Dec. 31, 2011
Fair Value of Financial Assets and Liabilities [Abstract]
Number of years of monthly revenues or charges holder of FTRs purchased from MISO is entitled (in years)	1
Non-Derivative Instruments Fair Value Measurements [Abstract]
Nuclear decommissioning fund available-for-sale securities, unrealized gains	$ 117,100,000				$ 79,800,000
Nuclear decommissioning fund available-for-sale securities, unrealized losses	65,700,000				87,500,000
Nuclear decommissioning fund [Abstract]
Cost	1,358,124,000	[1]			1,344,178,000	[2]
Other derivative instruments [Abstract]
Current derivative instruments	61,971,000				64,340,000
Other derivative instruments [Abstract]
Noncurrent derivative instruments	146,438,000				152,887,000
Other derivative instruments [Abstract]
Current derivative instruments	56,132,000				157,414,000
Other derivative instruments [Abstract]
Noncurrent derivative instruments	260,152,000				263,906,000
Investments [Abstract]
Equity investments in unconsolidated subsidiaries	92,300,000				92,700,000
Miscellaneous investments	35,700,000				34,300,000
Changes in Level 3 Nuclear Decommissioning Fund Assets [Roll Forward]
Balance	130,763,000		105,763,000
Purchases	18,695,000		46,869,000
Settlements	(18,495,000)		(27,783,000)
Gains (losses) recognized as regulatory assets and liabilities	2,228,000		(462,000)
Balance	133,191,000		124,387,000
Commodity Derivatives [Abstract]
Amount of accumulated other comprehensive gains (losses) related to commodity derivatives expected to be reclassified into earnings within the next twelve months	200,000
Financial Impact of Qualifying Fair Value Hedges [Abstract]
Derivative instruments designated as fair value hedges	0		0
Recognized gains (losses) from fair value hedges or related hedged transactions	0		0
Credit Related Contingent Features [Abstract]
Derivative instruments in a gross liability position	10,800,000				8,300,000
Payments required if credit ratings were downgraded below investment grade	9,400,000				9,300,000
Collateral posted on derivative instruments in a gross liability position	0				0
Collateral posted related to adequate assurance clauses in derivative contracts	0				0
Carrying Amount [Member]
Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, including current portion	9,908,044,000				9,908,435,000
Fair Value [Member]
Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, including current portion	11,414,894,000				11,734,798,000
Commodity Derivatives, Net [Member]
Changes in Level 3 Commodity Derivatives [Roll Forward]
Balance	12,417,000		2,392,000
Settlements	(8,884,000)		(7,790,000)
Net transactions recorded during the period [Abstract]
(Losses) gains recognized in earnings	(9,000)	[3]	68,000	[3]
Gains recognized as regulatory liabilities	1,800,000		7,662,000
Balance	5,324,000		2,332,000
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Cash Flow Hedges [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	41,883,000		389,000
Fair value changes recognized during the period in regulatory (assets) and liabilities	0		0
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	337,000		305,000
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	0		0
Pre-tax gains (losses) recognized during the period in income	0		0
Cash Flow Hedges [Member] | Interest Rate Contract [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	41,704,000		0
Fair value changes recognized during the period in regulatory (assets) and liabilities	0		0
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	389,000	[4]	337,000	[4]
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	0		0
Pre-tax gains (losses) recognized during the period in income	0		0
Cash Flow Hedges [Member] | Vehicle Fuel And Other Commodity Contract [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	179,000		389,000
Fair value changes recognized during the period in regulatory (assets) and liabilities	0		0
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	(52,000)	[5]	(32,000)	[5]
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	0		0
Pre-tax gains (losses) recognized during the period in income	0		0
Other Derivative Instruments [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	0		0
Fair value changes recognized during the period in regulatory (assets) and liabilities	(9,201,000)		1,231,000
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	0		0
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	72,967,000		48,499,000
Pre-tax gains (losses) recognized during the period in income	1,614,000		5,600,000
Other Derivative Instruments [Member] | Trading Commodity Contract [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	0		0
Fair value changes recognized during the period in regulatory (assets) and liabilities	0		0
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	0		0
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	0		0
Pre-tax gains (losses) recognized during the period in income	1,723,000	[6]	5,600,000	[6]
Other Derivative Instruments [Member] | Electric Commodity Contract [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	0		0
Fair value changes recognized during the period in regulatory (assets) and liabilities	1,582,000		8,846,000
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	0		0
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	(7,972,000)	[7]	(8,888,000)	[7]
Pre-tax gains (losses) recognized during the period in income	0		0
Other Derivative Instruments [Member] | Natural Gas Commodity Contract [Member]
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income [Abstract]
Fair value changes recognized during the period in accumulated other comprehensive loss	0		0
Fair value changes recognized during the period in regulatory (assets) and liabilities	(10,783,000)		(7,615,000)
Pre-tax amounts reclassified into income during the period from accumulated other comprehensive loss	0		0
Pre-tax amounts reclassified into income during the period from regulatory assets and (liabilities)	80,939,000	[8]	57,387,000	[8]
Pre-tax gains (losses) recognized during the period in income	(109,000)	[6]	0
Electric Commodity [Member]
Gross notional amounts of commodity forwards, options and FTRs [Abstract]
Notional amount	23,385,000	[10],[9]			38,822,000	[10],[9]
Natural Gas Commodity [Member]
Gross notional amounts of commodity forwards, options and FTRs [Abstract]
Notional amount	0	[10],[9]			40,736,000	[10],[9]
Vehicle Fuel Commodity [Member]
Gross notional amounts of commodity forwards, options and FTRs [Abstract]
Notional amount	550,000	[10],[9]			600,000	[10],[9]
Interest Rate Swap [Member]
Interest Rate Derivatives [Abstract]
Amount of accumulated other comprehensive gains (losses) related to interest rate derivatives expected to be reclassified into earnings within the next twelve months	900,000
Notional amount outstanding	475,000,000
Asset-backed Securities [Member]
Changes in Level 3 Nuclear Decommissioning Fund Assets [Roll Forward]
Balance	16,501,000		33,174,000
Purchases	0		756,000
Settlements	(1,000)		(7,910,000)
Gains (losses) recognized as regulatory assets and liabilities	47,000		0
Balance	16,547,000		26,020,000
Mortgage-backed Securities [Member]
Changes in Level 3 Nuclear Decommissioning Fund Assets [Roll Forward]
Balance	78,664,000		72,589,000
Purchases	6,904,000		46,113,000
Settlements	(16,728,000)		(19,873,000)
Gains (losses) recognized as regulatory assets and liabilities	(169,000)		(462,000)
Balance	68,671,000		98,367,000
Real Estate [Member]
Changes in Level 3 Nuclear Decommissioning Fund Assets [Roll Forward]
Balance	26,395,000
Purchases	1,636,000
Settlements	(1,766,000)
Gains (losses) recognized as regulatory assets and liabilities	1,640,000
Balance	27,905,000
Private Equity Investments [Member]
Changes in Level 3 Nuclear Decommissioning Fund Assets [Roll Forward]
Balance	9,203,000
Purchases	10,155,000
Settlements	0
Gains (losses) recognized as regulatory assets and liabilities	710,000
Balance	20,068,000
Fair Value Measured on a Recurring Basis [Member]
Nuclear decommissioning fund [Abstract]
Cash equivalents	12,383,000	[1]			26,123,000	[2]
Commingled funds	371,078,000	[1]			311,105,000	[2]
International equity funds	67,183,000	[1]			58,508,000	[2]
Private equity investments	20,068,000	[1]			9,203,000	[2]
Real estate	27,905,000	[1]			26,395,000	[2]
Debt securities [Abstract]
Government securities	131,401,000	[1]			117,256,000	[2]
U.S. corporate bonds	163,851,000	[1]			193,516,000	[2]
International corporate bonds	26,351,000	[1]			35,804,000	[2]
Municipal bonds	56,862,000	[1]			64,731,000	[2]
Asset-backed securities	16,547,000	[1]			16,501,000	[2]
Mortgage-backed securities	68,671,000	[1]			78,664,000	[2]
Equity securities [Abstract]
Common stock	447,205,000	[1]			398,625,000	[2]
Total	1,409,505,000	[1]			1,336,431,000	[2]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	306,000
Vehicle fuel and other commodity	208,000				93,000
Other derivative instruments [Abstract]
Trading commodity	23,288,000				19,291,000
Electric commodity	5,328,000				11,862,000
Total current derivative assets	29,130,000				31,246,000
Purchased power agreements	32,841,000	[11]			33,094,000	[11]
Current derivative instruments	61,971,000				64,340,000
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	94,000				48,000
Other derivative instruments [Abstract]
Trading commodity	32,744,000				31,059,000
Total noncurrent derivative assets	32,838,000				31,107,000
Purchased power agreements	113,600,000	[11]			121,780,000	[11]
Noncurrent derivative instruments	146,438,000				152,887,000
Derivatives designated as cash flow hedges [Abstract]
Interest rate	16,352,000				57,749,000
Other derivative instruments [Abstract]
Trading commodity	16,862,000				13,474,000
Electric commodity	0				143,000
Natural gas commodity					63,051,000
Total current derivative liabilities	33,214,000				134,417,000
Purchased power agreements	22,918,000	[11]			22,997,000	[11]
Current derivative instruments	56,132,000				157,414,000
Other derivative instruments [Abstract]
Trading commodity	17,333,000				15,367,000
Total noncurrent derivative liabilities	17,333,000				15,367,000
Purchased power agreements	242,819,000	[11]			248,539,000	[11]
Noncurrent derivative instruments	260,152,000				263,906,000
Fair Value Measured on a Recurring Basis [Member] | Level 1 [Member]
Nuclear decommissioning fund [Abstract]
Cash equivalents	8,023,000	[1]			7,103,000	[2]
Commingled funds	0	[1]			0	[2]
International equity funds	0	[1]			0	[2]
Private equity investments	0	[1]			0	[2]
Real estate	0	[1]			0	[2]
Debt securities [Abstract]
Government securities	0	[1]			0	[2]
U.S. corporate bonds	0	[1]			0	[2]
International corporate bonds	0	[1]			0	[2]
Municipal bonds	0	[1]			0	[2]
Asset-backed securities	0	[1]			0	[2]
Mortgage-backed securities	0	[1]			0	[2]
Equity securities [Abstract]
Common stock	447,205,000	[1]			398,625,000	[2]
Total	455,228,000	[1]			405,728,000	[2]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0
Vehicle fuel and other commodity	0				0
Other derivative instruments [Abstract]
Trading commodity	0				0
Electric commodity	0				0
Total current derivative assets	0				0
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	0				0
Other derivative instruments [Abstract]
Trading commodity	0				0
Total noncurrent derivative assets	0				0
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0				0
Other derivative instruments [Abstract]
Trading commodity	0				0
Electric commodity	0				0
Natural gas commodity					418,000
Total current derivative liabilities	0				418,000
Other derivative instruments [Abstract]
Trading commodity	0				0
Total noncurrent derivative liabilities	0				0
Fair Value Measured on a Recurring Basis [Member] | Level 2 [Member]
Nuclear decommissioning fund [Abstract]
Cash equivalents	4,360,000	[1]			19,020,000	[2]
Commingled funds	371,078,000	[1]			311,105,000	[2]
International equity funds	67,183,000	[1]			58,508,000	[2]
Private equity investments	0	[1]			0	[2]
Real estate	0	[1]			0	[2]
Debt securities [Abstract]
Government securities	131,401,000	[1]			117,256,000	[2]
U.S. corporate bonds	163,851,000	[1]			193,516,000	[2]
International corporate bonds	26,351,000	[1]			35,804,000	[2]
Municipal bonds	56,862,000	[1]			64,731,000	[2]
Asset-backed securities	0	[1]			0	[2]
Mortgage-backed securities	0	[1]			0	[2]
Equity securities [Abstract]
Common stock	0	[1]			0	[2]
Total	821,086,000	[1]			799,940,000	[2]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	306,000
Vehicle fuel and other commodity	208,000				169,000
Other derivative instruments [Abstract]
Trading commodity	39,483,000				32,682,000
Electric commodity	0				0
Total current derivative assets	39,997,000				32,851,000
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	209,000				107,000
Other derivative instruments [Abstract]
Trading commodity	38,214,000				36,599,000
Total noncurrent derivative assets	38,423,000				36,706,000
Derivatives designated as cash flow hedges [Abstract]
Interest rate	16,352,000				57,749,000
Other derivative instruments [Abstract]
Trading commodity	34,130,000				27,891,000
Electric commodity	0				698,000
Natural gas commodity					70,119,000
Total current derivative liabilities	50,482,000				156,457,000
Other derivative instruments [Abstract]
Trading commodity	22,918,000				20,966,000
Total noncurrent derivative liabilities	22,918,000				20,966,000
Fair Value Measured on a Recurring Basis [Member] | Level 3 [Member]
Nuclear decommissioning fund [Abstract]
Cash equivalents	0	[1]			0	[2]
Commingled funds	0	[1]			0	[2]
International equity funds	0	[1]			0	[2]
Private equity investments	20,068,000	[1]			9,203,000	[2]
Real estate	27,905,000	[1]			26,395,000	[2]
Debt securities [Abstract]
Government securities	0	[1]			0	[2]
U.S. corporate bonds	0	[1]			0	[2]
International corporate bonds	0	[1]			0	[2]
Municipal bonds	0	[1]			0	[2]
Asset-backed securities	16,547,000	[1]			16,501,000	[2]
Mortgage-backed securities	68,671,000	[1]			78,664,000	[2]
Equity securities [Abstract]
Common stock	0	[1]			0	[2]
Total	133,191,000	[1]			130,763,000	[2]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0
Vehicle fuel and other commodity	0				0
Other derivative instruments [Abstract]
Trading commodity	0				0
Electric commodity	5,898,000				13,333,000
Total current derivative assets	5,898,000				13,333,000
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	0				0
Other derivative instruments [Abstract]
Trading commodity	0				0
Total noncurrent derivative assets	0				0
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0				0
Other derivative instruments [Abstract]
Trading commodity	4,000				0
Electric commodity	570,000				916,000
Natural gas commodity					0
Total current derivative liabilities	574,000				916,000
Other derivative instruments [Abstract]
Trading commodity	0				0
Total noncurrent derivative liabilities	0				0
Fair Value Measured on a Recurring Basis [Member] | Fair Value Total [Member]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	306,000
Vehicle fuel and other commodity	208,000				169,000
Other derivative instruments [Abstract]
Trading commodity	39,483,000				32,682,000
Electric commodity	5,898,000				13,333,000
Total current derivative assets	45,895,000				46,184,000
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	209,000				107,000
Other derivative instruments [Abstract]
Trading commodity	38,214,000				36,599,000
Total noncurrent derivative assets	38,423,000				36,706,000
Derivatives designated as cash flow hedges [Abstract]
Interest rate	16,352,000				57,749,000
Other derivative instruments [Abstract]
Trading commodity	34,134,000				27,891,000
Electric commodity	570,000				1,614,000
Natural gas commodity					70,537,000
Total current derivative liabilities	51,056,000				157,791,000
Other derivative instruments [Abstract]
Trading commodity	22,918,000				20,966,000
Total noncurrent derivative liabilities	22,918,000				20,966,000
Fair Value Measured on a Recurring Basis [Member] | Counterparty Netting [Member]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0	[12]
Vehicle fuel and other commodity	0	[12]			(76,000)	[12]
Other derivative instruments [Abstract]
Trading commodity	(16,195,000)	[12]			(13,391,000)	[12]
Electric commodity	(570,000)	[12]			(1,471,000)	[12]
Total current derivative assets	(16,765,000)	[12]			(14,938,000)	[12]
Derivatives designated as cash flow hedges [Abstract]
Vehicle fuel and other commodity	(115,000)	[12]			(59,000)	[12]
Other derivative instruments [Abstract]
Trading commodity	(5,470,000)	[12]			(5,540,000)	[12]
Total noncurrent derivative assets	(5,585,000)	[12]			(5,599,000)	[12]
Derivatives designated as cash flow hedges [Abstract]
Interest rate	0	[12]			0	[12]
Other derivative instruments [Abstract]
Trading commodity	(17,272,000)	[12]			(14,417,000)	[12]
Electric commodity	(570,000)	[12]			(1,471,000)	[12]
Natural gas commodity					(7,486,000)	[12]
Total current derivative liabilities	(17,842,000)	[12]			(23,374,000)	[12]
Other derivative instruments [Abstract]
Trading commodity	(5,585,000)	[12]			(5,599,000)	[12]
Total noncurrent derivative liabilities	(5,585,000)	[12]			(5,599,000)	[12]
Cash Equivalents [Member]
Nuclear decommissioning fund [Abstract]
Cost	12,383,000	[1]			26,123,000	[2]
Commingled Funds [Member]
Nuclear decommissioning fund [Abstract]
Cost	374,523,000	[1]			320,798,000	[2]
International Equity Funds [Member]
Nuclear decommissioning fund [Abstract]
Cost	65,712,000	[1]			63,781,000	[2]
Private Equity Investments [Member]
Nuclear decommissioning fund [Abstract]
Cost	19,358,000	[1]			9,203,000	[2]
Real Estate [Member]
Nuclear decommissioning fund [Abstract]
Cost	26,265,000	[1]			24,768,000	[2]
Debt Securities [Member]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	113,004,000
Due in 1 to 5 Years	59,688,000
Due in 5 to 10 Years	179,261,000
Due after 10 Years	111,730,000
Total	463,683,000
Government Securities [Member]
Nuclear decommissioning fund [Abstract]
Cost	131,152,000	[1]			116,490,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	113,004,000
Due in 1 to 5 Years	701,000
Due in 5 to 10 Years	17,696,000
Due after 10 Years	0
Total	131,401,000
U.S. Corporate Bonds [Member]
Nuclear decommissioning fund [Abstract]
Cost	156,602,000	[1]			187,083,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	0
Due in 1 to 5 Years	37,556,000
Due in 5 to 10 Years	112,103,000
Due after 10 Years	14,192,000
Total	163,851,000
International Corporate Bonds [Member]
Nuclear decommissioning fund [Abstract]
Cost	25,187,000	[1]			35,198,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	0
Due in 1 to 5 Years	8,162,000
Due in 5 to 10 Years	18,186,000
Due after 10 Years	3,000
Total	26,351,000
Municipal Bonds [Member]
Nuclear decommissioning fund [Abstract]
Cost	53,895,000	[1]			60,469,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	0
Due in 1 to 5 Years	0
Due in 5 to 10 Years	27,039,000
Due after 10 Years	29,823,000
Total	56,862,000
Asset-backed Securities [Member]
Nuclear decommissioning fund [Abstract]
Cost	16,515,000	[1]			16,516,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	0
Due in 1 to 5 Years	13,269,000
Due in 5 to 10 Years	3,278,000
Due after 10 Years	0
Total	16,547,000
Mortgage-backed Securities [Member]
Nuclear decommissioning fund [Abstract]
Cost	65,803,000	[1]			75,627,000	[2]
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	0
Due in 1 to 5 Years	0
Due in 5 to 10 Years	959,000
Due after 10 Years	67,712,000
Total	68,671,000
Common Stock [Member]
Nuclear decommissioning fund [Abstract]
Cost	$ 410,729,000	[1]			$ 408,122,000	[2]

[1] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheet, which also includes $92.3 million of equity investments in unconsolidated subsidiaries and $35.7 million of miscellaneous investments.

[2] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheet, which also includes $92.7 million of equity investments in unconsolidated subsidiaries and $34.3 million of miscellaneous investments.

[3] These amounts relate to commodity derivatives held at the end of the period.

[4] Recorded to interest charges.

[5] Recorded to O&M expenses.

[6] Recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue, as appropriate.

[7] Recorded to electric fuel and purchased power. These derivative settlement gains and losses are shared with electric customers through fuel and purchased energy cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.

[8] Recorded to cost of natural gas sold and transported. These derivative settlement gains and losses are shared with natural gas customers through purchased natural gas cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.

[9] Amounts are not reflective of net positions in the underlying commodities.

[10] Notional amounts for options are included on a gross basis, but are weighted for the probability of exercise.

[11] In 2003, as a result of implementing new guidance on the normal purchase exception for derivative accounting, Xcel Energy began recording several long-term purchased power agreements at fair value due to accounting requirements related to underlying price adjustments. As these purchases are recovered through normal regulatory recovery mechanisms in the respective jurisdictions, the changes in fair value for these contracts were offset by regulatory assets and liabilities. During 2006, Xcel Energy qualified these contracts under the normal purchase exception. Based on this qualification, the contracts are no longer adjusted to fair value and the previous carrying value of these contracts will be amortized over the remaining contract lives along with the offsetting regulatory assets and liabilities.

[12] The accounting guidance for derivatives and hedging permits the netting of receivables and payables for derivatives and related collateral amounts when a legally enforceable master netting agreement exists between Xcel Energy and a counterparty. A master netting agreement is an agreement between two parties who have multiple contracts with each other that provides for the net settlement of all contracts in the event of default on or termination of any one contract.