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Jointly-owned Plant | 12 Months Ended
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Dec. 31, 2010
Jointly-owned Plant Note [Abstract] |
Jointly-owned Plant [Text Block] | JOINTLY-OWNED PLANT PGE has interests in three jointly-owned generating facilities. Under the joint operating agreements, each participating owner is responsible for financing its share of construction, operating and leasing costs. PGE’s proportionate share of direct operating and maintenance expenses of the facilities is included in the corresponding operating and maintenance expense categories in the consolidated statements of income. As of December 31, 2011, PGE had the following investments in jointly-owned plant (dollars in millions):
| PGE Share |  | In-service Date |  | Plant In-service |  | Accumulated Depreciation* |  | Construction Work In Progress
Boardman | 65.00 | % |  | 1980 |  | $ | 467 |  |  | $ | 292 |  |  | $ | 2 |
Colstrip | 20.00 |  |  | 1986 |  | 507 |  |  | 326 |  |  | 2 |
Pelton/Round Butte | 66.67 |  |  | 1958 | / | 1964 |  | 206 |  |  | 46 |  |  | 11 |
Total |  |  |  |  |  |  | $ | 1,180 |  |  | $ | 664 |  |  | $ | 15 |
* | Excludes asset retirement obligations and accumulated asset retirement removal costs.

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- Definition Jointly-owned Plant [Text Block] + References No definition available. + Details
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