v3.20.1

Accounting for derivative instruments and hedging activities (Details) MMBTU in Millions, $ in Millions, J in Billions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 31, 2020 | Mar. 31, 2020 USD ($) J MMBTU item contract $ / J | Dec. 31, 2019 USD ($) MMBTU
Derivative instruments designated as cash flow hedges |  |  |
Derivative instruments |  |  |
Number of derivative contracts designated as cash flow hedges | item |  | 1 |
Adjusted Eurodollar Rate |  |  |
Derivative instruments |  |  |
Applicable margin (as a percent) |  | 2.50% |
Nipigon Project |  |  |
Derivative instruments |  |  |
Notional amount, energy (in joules: Ontario, in Mmbtu: Orlando and Morris) | J |  | 6,500 |
Gas purchase agreements | Nipigon Project |  |  |
Derivative instruments |  |  |
Price per Gj | $ / J |  | 4.57 |
Gas purchase agreements | Nipigon Project | Minimum |  |  |
Derivative instruments |  |  |
Notional amount, energy (in joules: Ontario, in Mmbtu: Orlando and Morris) | J |  | 6,500 |
Natural gas swaps |  |  |
Derivative instruments |  |  |
Notional amount, energy (in joules: Ontario, in Mmbtu: Orlando and Morris) | MMBTU |  | 15.4 | 16.3
Natural gas swaps | Orlando project |  |  |
Derivative instruments |  |  |
Amount of future natural gas purchases to fix the price (in Mmbtu) | MMBTU |  | 15.4 |
Natural gas swaps during 2016 | Orlando project |  |  |
Derivative instruments |  |  |
Percentage of the entity's share in required natural gas purchases hedge |  | 100.00% |
Interest rate swaps |  |  |
Derivative instruments |  |  |
Notional amount |  | $ 346.6 | $ 468.4
Derivative, Average Swaption Interest Rate |  | 2.03% |
Swaption interest rate (as a percent) |  | 4.53% |
Interest rate swaps | Adjusted Eurodollar Rate |  |  |
Derivative instruments |  |  |
Derivative, Floor Interest Rate |  | 1.00% |
Interest rate swaps | Minimum |  |  |
Derivative instruments |  |  |
Minimum fixed interest rate (as a percent) |  | 3.50% |
Interest rate swaps | Swaption interest rate until February 15, 2023 | Cadillac Project |  |  |
Derivative instruments |  |  |
Swaption interest rate (as a percent) |  | 6.30% |
Interest rate swaps | Swaption interest rate after February 15, 2023 | Cadillac Project |  |  |
Derivative instruments |  |  |
Swaption interest rate (as a percent) |  | 6.40% |
Foreign currency forward contracts | Derivative instruments not designated as cash flow hedges |  |  |
Derivative instruments |  |  |
Number of forward contracts | contract |  | 0 |
APLP Holdings | Senior secured term loans |  |  |
Derivative instruments |  |  |
Face amount of debt |  | $ 700.0 |
Applicable margin (as a percent) | 2.50% |  |
APLP Holdings | Interest rate swaps | Adjusted Eurodollar Rate | Senior secured term loans | Long-term debt excluding debentures |  |  |
Derivative instruments |  |  |
Notional amount |  | 360.0 |
Remaining aggregate principal amount |  | 329.4 |
Face amount of debt |  | $ 360.0 |
APLP Holdings | Interest rate swaps | Derivative Swaption Interest Rate from Mar 31 2020 to December 31 2021 | One-month LIBOR | New term loan facility |  |  |
Derivative instruments |  |  |
Swaption interest rate (as a percent) |  | 1.39% |
APLP Holdings | Interest rate swaps | Derivative Swaption Interest Rate from Mar 31 2020 to December 31 2021 | Minimum | New term loan facility |  |  |
Derivative instruments |  |  |
Notional amount |  | $ 3.1 |
APLP Holdings | Interest rate swaps | Derivative Swaption Interest Rate from Mar 31 2020 to December 31 2021 | Maximum | New term loan facility |  |  |
Derivative instruments |  |  |
Notional amount |  | $ 100.0 |

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