v3.4.0.3

Accounting for derivative instruments and hedging activities (Details) CAD in Millions, $ in Millions |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
May. 05, 2014 USD ($) | May. 05, 2014 USD ($) | Jun. 30, 2014 MMBTU | Mar. 31, 2016 USD ($) MMBTU | Mar. 31, 2015 USD ($) | Dec. 31, 2015 USD ($) MMBTU | Mar. 31, 2016 CAD item | Mar. 31, 2016 USD ($) item | Feb. 14, 2014 USD ($)
Derivative instruments |  |  |  |  |  |  |  |  |
Derivative Number of Contracts Designated as Cash Flow Hedges | item |  |  |  |  |  |  | 1 | 1 |
Long-term debt | CAD |  |  |  |  |  |  | CAD 210.0 |  |
Long-term debt excluding debentures |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  | $ (15.8) |  | $ (15.7) |
Senior secured term loan, due 2021 | Long-term debt excluding debentures |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  | $ 473.2 |  | 447.9 |
Adjusted Eurodollar Rate |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Minimum percentage of variable rate base |  | 1.00% |  |  |  |  |  |  |
Applicable margin (as a percent) |  | 3.75% |  |  |  |  |  |  |
Gas purchase agreements | Ontario project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount, energy (in gigajoules: Ontario, in Mmbtu: Orlando) | MMBTU |  |  | 2,900,000 |  |  |  |  |  |
Gas purchase agreements | Morris Project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount, energy (in gigajoules: Ontario, in Mmbtu: Orlando) | MMBTU |  |  |  | 450,000 |  |  |  |  |
Expected uncontracted gas requirements for 2015 | Ontario project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Percentage of requirements whose price is fixed by derivative |  |  |  | 100.00% |  |  |  |  |
Expected uncontracted gas requirements for 2016 | Ontario project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Percentage of requirements whose price is fixed by derivative |  |  |  | 35.00% |  |  |  |  |
Expected uncontracted gas requirements for 2017 | Ontario project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Percentage of requirements whose price is fixed by derivative |  |  |  | 30.00% |  |  |  |  |
Natural gas swaps |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount, energy (in gigajoules: Ontario, in Mmbtu: Orlando) | MMBTU |  |  |  | 6,700,000 |  | 2,800,000 |  |  |
Natural gas swaps | Derivative instruments not designated as cash flow hedges |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Derivatives |  |  |  | $ 2.0 | $ 12.0 |  |  |  |
Natural gas swaps during remainder of 2014 | Orlando project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount, energy (in gigajoules: Ontario, in Mmbtu: Orlando) | MMBTU |  |  |  | 7,700,000 |  |  |  |  |
Percentage of the entity's share in required natural gas purchases hedge |  |  |  | 95.00% |  |  |  |  |
Interest rate swaps |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Minimum fixed interest rate (as a percent) | 4.75% | 4.75% |  |  |  |  |  |  |
Notional amount |  |  |  |  |  | $ 302.3 |  | 228.9 |
Maximum fixed interest rate (as a percent) | 4.91% | 4.91% |  |  |  |  |  |  |
Interest rate swaps | Derivative instruments not designated as cash flow hedges |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Derivatives |  |  |  | $ 0.6 | $ (1.0) |  |  |  |
Interest rate swaps | Adjusted Eurodollar Rate |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount | $ 199.0 | $ 199.0 |  |  |  |  |  | 140.4 |
Aggregate principal amount of debt |  |  |  |  |  |  |  | $ 447.9 |
Interest rate swaps | Adjusted Eurodollar Rate | Senior secured term loan, due 2021 | Long-term debt excluding debentures |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Notional amount | 199.0 | 199.0 |  |  |  |  |  |  |
Aggregate principal amount of debt | $ 600.0 | $ 600.0 |  |  |  |  |  |  |
Interest rate swaps | Adjusted Eurodollar Rate | Derivative instruments not designated as cash flow hedges |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) | 1.16% | 1.16% |  |  |  |  |  |  |
Interest rate swaps | Adjusted Eurodollar Below One Percent |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption all in one interest rate (as a percent) | 4.75% | 4.75% |  |  |  |  |  |  |
Interest rate swaps | Minimum | Adjusted Eurodollar Rate |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Minimum percentage of variable rate base | 1.00% |  |  |  |  |  |  |  |
Interest rate swaps | Piedmont |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  | $ 68.5
Interest rate swaps | Swaption interest rate until February 15, 2015 | Cadillac Project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 6.00% | 6.00% |
Interest rate swaps | Swaption interest rate from February 16, 2015 to February 15, 2019 | Cadillac Project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 6.10% | 6.10% |
Interest rate swaps | Swaption interest rate from February 16, 2019 to February 15, 2023 | Cadillac Project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 6.30% | 6.30% |
Interest rate swaps | Swaption interest rate after February 15, 2023 | Cadillac Project |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 6.40% | 6.40% |
Interest rate swaps | Swaption interest rate until February 29, 2016 | Piedmont |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 1.70% | 1.70% |
Applicable margin, low end of range (as a percent) |  |  |  |  |  |  | 3.50% | 3.50% |
Applicable margin, high end of range (as a percent) |  |  |  |  |  |  | 3.80% | 3.80% |
Interest rate swaps | Swaption interest rate from February, 2016 to November, 2017 | Piedmont |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 4.47% | 4.47% |
Applicable margin of derivative (as a percent) |  |  |  |  |  |  | 4.00% | 4.00% |
Swaption all in one interest rate (as a percent) |  |  |  |  |  |  | 8.50% | 8.50% |
Interest rate swaps | Swaption interest rate from November, 2017 to November, 2030 | Piedmont |  |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |  |
Swaption interest rate (as a percent) |  |  |  |  |  |  | 4.47% | 4.47% |

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