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v3.19.3.a.u2

Note 13 - Property, Plant and Equipment (Tables) | 12 Months Ended
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Dec. 31, 2019
Notes Tables |
Property, Plant and Equipment [Table Text Block] |
(in thousands) |  | December 31, 2019 |  |  | December 31, 2018 |
Electric Plant in Service |  |  |  |  |  |  |  |
Production |  | $ | 915,996 |  |  | $ | 905,224 |
Transmission |  |  | 647,474 |  |  |  | 512,832 |
Distribution |  |  | 526,146 |  |  |  | 502,261 |
General |  |  | 123,268 |  |  |  | 99,404 |
Electric Plant in Service |  |  | 2,212,884 |  |  |  | 2,019,721 |
Construction Work in Progress |  |  | 177,584 |  |  |  | 170,090 |
Total Gross Electric Plant |  |  | 2,390,468 |  |  |  | 2,189,811 |
Less Accumulated Depreciation and Amortization |  |  | 731,110 |  |  |  | 699,642 |
Net Electric Plant |  | $ | 1,659,358 |  |  | $ | 1,490,169 |
Nonelectric Operations Plant |  |  |  |  |  |  |  |
Equipment |  | $ | 187,904 |  |  | $ | 170,634 |
Buildings and Leasehold Improvements |  |  | 53,412 |  |  |  | 53,011 |
Land |  |  | 6,040 |  |  |  | 4,475 |
Nonelectric Operations Plant |  |  | 247,356 |  |  |  | 228,120 |
Construction Work in Progress |  |  | 7,654 |  |  |  | 11,536 |
Total Gross Nonelectric Plant |  |  | 255,010 |  |  |  | 239,656 |
Less Accumulated Depreciation and Amortization |  |  | 160,574 |  |  |  | 148,727 |
Net Nonelectric Operations Plant |  | $ | 94,436 |  |  | $ | 90,929 |
Net Plant |  | $ | 1,753,794 |  |  | $ | 1,581,098 |
Schedule of Useful Lives for Property, Plant Equipment [Table Text Block] |
|  | Service Life Range |
(years) |  | Low |  |  | High |
Electric Fixed Assets: |  |  |  |  |  |
Production Plant |  | 9 |  |  | 82 |
Transmission Plant |  | 51 |  |  | 75 |
Distribution Plant |  | 15 |  |  | 70 |
General Plant |  | 5 |  |  | 57 |
Nonelectric Fixed Assets: |  |  |  |  |  |
Equipment |  | 2 |  |  | 12 |
Buildings and Leasehold Improvements |  | 5 |  |  | 40 |

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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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