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Operations and Significant Accounting Policies - Revision of Prior Balance Sheet (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($)
Regulatory Assets [Member] |
Revision of Prior Balance Sheet [Line Items] |
Immaterial Revision | $ 29.5
Deferred Income Taxes [Member] |
Revision of Prior Balance Sheet [Line Items] |
Immaterial Revision | $ 29.5

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- Definition Amount of each individual error being corrected in the correcting adjustment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 1.N) -URI http://asc.fasb.org/extlink&oid=26874127&loc=d3e30840-122693 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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