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Organization and Basis of Presentation (Details 4) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Annual Composite Depreciation Rate |  |  |
Annual Composite Depreciation Rate (percent) | 2.50% | 2.50% | 2.50%
FES |  |  |
Annual Composite Depreciation Rate |  |  |
Annual Composite Depreciation Rate (percent) | 3.30% | 3.20% | 3.10%

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- Definition Annual composite depreciation rate. + References No definition available. + Details
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- Definition Composite depreciation rate for public utility plants in service. + References No definition available. + Details
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- Details
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