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Regulatory Assets and Liabilities (Other) (Details) CAD in Millions, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2016 USD ($) | Dec. 31, 2016 CAD | Dec. 31, 2015 CAD
Regulatory Assets [Line Items] |  |  |
Regulatory Assets |  | CAD 1,322 | CAD 699
TECO Energy Inc [Member] |  |  |
Regulatory Assets [Line Items] |  |  |
Public Utilities Annual Bill Reduction To Customers | $ | $ 4 |  |
TECO Energy Inc [Member] | Storm Costs [Member] |  |  |
Regulatory Assets [Line Items] |  |  |
Regulatory Assets |  | CAD 11 |
Tampa Electric Division [Member] | Storm Costs [Member] |  |  |
Regulatory Assets [Line Items] |  |  |
Regulatory Assets |  |  | CAD 11

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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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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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