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Balance Sheet Components (Policies) | 12 Months Ended
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Dec. 31, 2012
Balance Sheet Components [Abstract] |
Preliminary Engineering [Policy Text Block] | The Company incurs preliminary engineering costs related to potential future capital projects, which are capitalized in Other noncurrent assets in the consolidated balance sheets. Preliminary engineering costs consist of expenditures for preliminary surveys, plans, and investigations made for the purpose of determining the feasibility of utility projects being considered. Once the project is approved for construction, such costs are reclassified to Construction work in progress within Electric utility plant. If the project is abandoned, such costs are expensed to Production and distribution expense in the period such determination is made. If any preliminary engineering costs are expensed, the Company may seek recovery of such costs in customer prices, although there can be no guarantee such recovery would be granted.

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- Definition Preliminary Engineering [Policy Text Block] + References No definition available. + Details
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