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Commitments, Guarantees and Contingencies - North Dakota Wind Development (Details) (USD $) In Millions, unless otherwise specified | Sep. 30, 2011
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North Dakota Wind Development [Line Items] |
Capital Cost Spent to Date | $ 19.7
Bison 1 Wind Project [Member] |
North Dakota Wind Development [Line Items] |
Number of Phases | 2
Generating Unit Capacity (MW) | 82
Expected Capital Cost | 177
Capital Cost Spent to Date | 158.8
MPUC, Current Cost Recovery, Approval Date | 2009
MPUC, Rates, Approval Date | July 2010
MPUC, Rates, Effective Date | Aug. 1, 2010
MPUC, Updated Rates, Filing Date | Mar. 31, 2011
Bison 1 Wind Project, Phase 1 [Member] |
North Dakota Wind Development [Line Items] |
Transmission Line Capacity (kV) | 230
Transmission Line Length (Miles) | 22
Number of Turbines | 16
Capacity of Turbines (MW) | 2.3
Project Completion Date | 2010
Bison 1 Wind Project, Phase 2 [Member] |
North Dakota Wind Development [Line Items] |
Number of Turbines | 15
Capacity of Turbines (MW) | 3.0
Project Completion Date | 2011
Bison 2 Wind Project [Member] |
North Dakota Wind Development [Line Items] |
MPUC, Project, Approval Date | Aug. 24, 2011
NDPSC, Site Permit, Approval Date | Aug. 10, 2011
Bison 3 Wind Project [Member] |
North Dakota Wind Development [Line Items] |
MPUC, Project, Approval Date | Oct. 12, 2011
NDPSC, Site Permit, Approval Date | Oct. 20, 2011
Bison 2 and 3 Wind Projects [Member] |
North Dakota Wind Development [Line Items] |
Generating Unit Capacity (MW) | 105
Project Completion Date | 2012
Expected Capital Cost | $ 160
DC Transmission Line from Square Butte [Member] |
North Dakota Wind Development [Line Items] |
Transmission Line Capacity (kV) | 250
Transmission Line Length (Miles) | 465
Transmission Line Purchase Date | December 2009

X
- Definition Capacity of each turbine in megawatts at a site. + Details
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- Definition Capacity of each generating unit/individual project in megawatts. + Details
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- Definition Date/expected date of approval by the Minnesota Public Utilities Commission (MPUC) of current cost recovery for expenditures and investments related to a project. + Details
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- Definition Date/expected date of project approval by the Minnesota Public Utilities Commission (MPUC). + Details
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- Definition Date/expected date of approval by the Minnesota Public Utilities Commission (MPUC) establishing rates. + Details
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- Definition Effective date of established rates as approved by the Minnesota Public Utilities Commission (MPUC). + Details
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- Definition Filing date of petition to the Minnesota Public Utilities Commission (MPUC) seeking updated rates for additional investments and expenditures. + Details
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- Definition Date/expected date of approval of site permit by the North Dakota Public Service Commission (NDPSC). + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + Details
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- Definition Number of phases for project. + Details
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- Definition Number of turbines at a site. + Details
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