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Property Plant and Equipment Joint Ownership (Details) $ in Millions | Dec. 31, 2018 USD ($)
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NSP-Minnesota |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 1,725
Accumulated Depreciation | 594
CWIP | 4
NSP-Minnesota | Electric Generation | Sherco Unit 3 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | 604
Accumulated Depreciation | 415
CWIP | $ 1
Ownership percentage (in hundredths) | 59.00%
NSP-Minnesota | Electric Generation | Sherco Common Facilities Units 1, 2 and 3 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 145
Accumulated Depreciation | 100
CWIP | $ 1
Ownership percentage (in hundredths) | 80.00%
NSP-Minnesota | Electric Generation | Sherco Substation |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 5
Accumulated Depreciation | 4
CWIP | $ 0
Ownership percentage (in hundredths) | 59.00%
NSP-Minnesota | Electric Transmission | Grand Meadow Line and Substation |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 960
Accumulated Depreciation | 73
CWIP | $ 2
Ownership percentage (in hundredths) | 51.00%
NSP-Minnesota | Electric Transmission | Other joint ownership [Domain] |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 11
Accumulated Depreciation | 2
CWIP | $ 0
Ownership percentage (in hundredths) | 50.00%
NSP-Wisconsin |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 344
Accumulated Depreciation | 17
CWIP | 2
NSP-Wisconsin | Electric Transmission | CapX2020 Transmission |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | 169
Accumulated Depreciation | 15
CWIP | $ 2
Ownership percentage (in hundredths) | 81.00%
NSP-Wisconsin | Electric Transmission | La Crosse, Wis. to Madison, Wis. |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 175
Accumulated Depreciation | 2
CWIP | $ 0
Ownership percentage (in hundredths) | 37.00%
PSCo |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 1,590
Accumulated Depreciation | 430
CWIP | 1
PSCo | Electric Generation | Hayden Unit 1 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | 153
Accumulated Depreciation | 76
CWIP | $ 0
Ownership percentage (in hundredths) | 76.00%
PSCo | Electric Generation | Hayden Unit 2 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 149
Accumulated Depreciation | 68
CWIP | $ 0
Ownership percentage (in hundredths) | 37.00%
PSCo | Electric Generation | Hayden Common Facilities |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 41
Accumulated Depreciation | 21
CWIP | $ 0
Ownership percentage (in hundredths) | 53.00%
PSCo | Electric Generation | Craig Units 1 and 2 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 81
Accumulated Depreciation | 40
CWIP | $ 0
Ownership percentage (in hundredths) | 10.00%
PSCo | Electric Generation | Craig Common Facilities 1, 2 and 3 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 39
Accumulated Depreciation | 21
CWIP | $ 0
Ownership percentage (in hundredths) | 7.00%
PSCo | Electric Generation | Comanche Unit 3 |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 886
Accumulated Depreciation | 130
CWIP | $ 0
Ownership percentage (in hundredths) | 67.00%
PSCo | Electric Generation | Comanche Common Facilities |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 28
Accumulated Depreciation | 3
CWIP | $ 0
Ownership percentage (in hundredths) | 82.00%
PSCo | Electric Transmission | Transmission and Other Facilities, including Substations |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 183
Accumulated Depreciation | 63
CWIP | 1
PSCo | Gas Transportation | Rifle to Avon |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | 22
Accumulated Depreciation | 7
CWIP | $ 0
Ownership percentage (in hundredths) | 60.00%
PSCo | Gas Transportation | Gas Transportation Compressor |
Jointly Owned Utility Plant Interests [Line Items] |
Plant in Service | $ 8
Accumulated Depreciation | 1
CWIP | $ 0
Ownership percentage (in hundredths) | 50.00%

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