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Balance Sheet Components Net Utility Property (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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Balance Sheet Components [Abstract] |  |
Utility plant in service | $ 6,060,373 | $ 5,853,308
Construction work in progress | 180,237 | 157,839
Total | 6,240,610 | 6,011,147
Less: Accumulated depreciation and amortization | 1,685,170 | 1,612,337
Total net utility property | $ 4,555,440 | $ 4,398,810

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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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