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Income Taxes (Effective Tax Rate) (Details) - CAD CAD in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Income before provision for income taxes | CAD 244 | CAD 545
Statutory income tax rate | 31.00% | 31.00%
Income taxes, at statutory income tax rates | CAD 76 | CAD 169
Deferred income taxes on regulated income recorded as regulatory assets and regulatory liabilities | (47) | (31)
Financing deductions | 17 | 10
Manufacturing And Investment Allowances | (7) | (5)
Foreign tax rate variance | (5) | 2
Tax effect of equity earnings | (10) | (11)
Other | 1 | (3)
Income Tax Expense (Benefit), Total | CAD (22) | CAD 93
Effective Income Tax Rate Reconciliation, Percent | (9.00%) | 17.00%
TECO Energy Inc [Member] |  |
Non-taxable portion of mark-to-market gains related to pending TECO Energy acquisition | CAD 21 | CAD (18)
Algonquin Power and Utilities Corporation [Member] |  |
Non-taxable portion of gains on transactions | CAD (34) | CAD 0

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