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The minimum number of utility, oil, chemical and coal companies against which a lawsuit was filed in U.S. District Court in Mississippi.

+ References

No definition available.

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- Definition

Number of lawsuits filed arising out of a dispute concerning payments for energy produced from the John Deere Wind Energy subsidiaries' (JD Wind) projects.

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No definition available.

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- Definition

The number of other entities against which the native village of Kivalina has filed a lawsuit to relocate the village of Kivalina, Alaska.

+ References

No definition available.

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- Definition

The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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The increase (decrease) in the period in loss contingency liabilities.

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- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14557-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 14

-Paragraph 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Topic 450

-SubTopic 20

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-Paragraph 4

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- Definition

The estimated minimum amount of possible loss from the contingency.

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Commitments and Contingencies, Legal Contingencies (Details) (USD $)							3 Months Ended
	Jun. 30, 2012 Native Village of Kivalina vs. Xcel Energy Inc. et al. [Member]	Feb. 29, 2008 Native Village of Kivalina vs. Xcel Energy Inc. et al. [Member]	Jun. 30, 2012 Comer vs. Xcel Energy Inc. et al. [Member]	May 31, 2011 Comer vs. Xcel Energy Inc. et al. [Member]	Jun. 30, 2012 Exelon Wind (formerly John Deere Wind) Complaint [Member]	Jun. 30, 2012 Exelon Wind Complaint - State Lawsuit Regarding Disputed Energy Payments [Member]	Jun. 20, 2012 Exelon Wind Complaint - State Lawsuit Regarding Wind Facility Registration with Southwest Power Pool (SPP) [Member]
Legal Contingencies [Abstract]
Number of other entities against which the native village of Kivalina has filed a lawsuit		23
Estimated cost of relocating the village of Kivalina, low end of range	$ 95,000,000
Estimated cost of relocating the village of Kivalina, high end of range	400,000,000
Accrual for legal contingency	0		0			0
Minimum number of utility, oil, chemical and coal companies against which a lawsuit was filed in U.S. District Court in Mississippi				85
Number of lawsuits filed related to disputed energy payments					4
Accrual for legal contingency							$ 2,000,000