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Regulatory Assets and Liabilities (ROE of Tampa Electric) (Details) - Tampa Electric Division [Member] - Florida Public Service Commission [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Public Utilities, General Disclosures [Line Items] |
Public Utilities, Approved Rate Increase (Decrease), Amount | $ 110
Public Utilities Approved Return On Equity Percentage Trigger Rate Minimum | 9.25%
Public Utilities Approved Return On Equity Percentage Trigger Rate Maximum | 11.25%
Public Utilities, Approved Equity Capital Structure, Percentage | 54.00%
Minimum [Member] |
Public Utilities, General Disclosures [Line Items] |
Public Utilities, Approved Return on Equity, Percentage | 9.25%
Maximum [Member] |
Public Utilities, General Disclosures [Line Items] |
Public Utilities, Approved Return on Equity, Percentage | 11.25%

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- Definition Minumum trigger rate percentage of public utility's approved return on equity to allow utility to request early rate increase + References No definition available. + Details
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- Definition Percentage of public utility's approved equity to capital, including debt and equity. + References No definition available. + Details
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- Details
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