v3.19.3.a.u2

Long-term debt - Credit Facilities (Details) $ in Millions, $ in Millions		1 Months Ended
	Apr. 16, 2016	Jan. 31, 2020 USD ($)	Oct. 31, 2018	Apr. 30, 2018	Oct. 31, 2017	Apr. 30, 2017	Dec. 31, 2019 CAD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 13, 2016 USD ($)
Debt Instrument [Line Items]
Total debt								$ 560.4
Original issue discount amount								5.8	$ 9.0
Subsequent event
Debt Instrument [Line Items]
Applicable margin (as a percent)		2.50%
Minimum percentage of variable rate base		1.00%
Credit Facilities
Debt Instrument [Line Items]
Applicable margin (as a percent)			2.75%	3.00%
Original issue discount (as a percent)	3.00%
Commitment fee related to New Revolver, as a percent	0.75%
Interest rate margin reduction due to repricing, as a percent			0.25%	0.50%	0.75%	0.75%
Credit Facilities | Minimum
Debt Instrument [Line Items]
Applicable margin (as a percent)	4.00%
Credit Facilities | Maximum
Debt Instrument [Line Items]
Applicable margin (as a percent)	5.00%
Credit Facilities | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin (as a percent)					3.50%	4.25%
Senior secured term loans
Debt Instrument [Line Items]
Total debt								380.0
Letters of credit
Debt Instrument [Line Items]
Face amount of debt								$ 78.3
Senior unsecured notes, due June 2036
Debt Instrument [Line Items]
Amount drawn under loan							$ 210.0
APLP Holdings | Credit Facilities
Debt Instrument [Line Items]
Amount of cash flow of APLP Holdings and its subsidiaries remaining after application of funds according to the Credit Agreement to be applied under										50.00%
APLP Holdings | Credit Facilities | Maximum
Debt Instrument [Line Items]
Other percentage of cash flow required to reduce aggregate principal amount of new term loans outstanding to achieve target principal amount that declines										100.00%
APLP Holdings | Credit Facilities | from June 30, 2020 | Minimum
Debt Instrument [Line Items]
Leverage ratio as defined in Credit Agreement							4.25	4.25
APLP Holdings | Credit Facilities | from June 30, 2020 | Maximum
Debt Instrument [Line Items]
Leverage ratio as defined in Credit Agreement							5.00	5.00
APLP Holdings | Credit Facilities | from June 30, 2022 | Minimum
Debt Instrument [Line Items]
Interest coverage ratio as defined in Credit Agreement							3.25	3.25
APLP Holdings | Credit Facilities | from June 30, 2022 | Maximum
Debt Instrument [Line Items]
Interest coverage ratio as defined in Credit Agreement							4.00	4.00
APLP Holdings | Senior secured term loans
Debt Instrument [Line Items]
Face amount of debt										$ 700.0
Prepayment of term loans if change of control occurs, as a percentage of par										101.00%
Percent of principal amount required to be repaid, prepaid, refinanced or replaced if APLP elects to do so within one year of initial funding date										101.00%
APLP Holdings | Senior secured term loans | Subsequent event
Debt Instrument [Line Items]
Applicable margin (as a percent)		2.50%
Debt repriced		$ 380.0
Interest rate margin reduction due to repricing, as a percent		0.25%
Interest rate margin additional reduction due to repricing, as a percent		0.25%
Leverage ratio as defined in Credit Agreement		2.75
Minimum percentage of variable rate base		1.00%
Term loan maturity		2 years
APLP Holdings | Senior secured term loan, due 2021
Debt Instrument [Line Items]
Face amount of debt										$ 200.0

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The percentage of additional reduction on the interest rate margin due to repricing the debt instrument effective in the event the Leverage Ratio is as defined in the Credit Agreement .

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The percentage of reduction on the interest rate margin due to repricing the debt instrument.

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Represents the minimum reference rate for variable rate of debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized as a percentage of total debt issued.

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The interest coverage ratio as defined in the Credit Agreement, which is part of the requirements in the negative covenants of the Credit Agreement.

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The leverage ratio as defined in the Credit Agreement, which is part of the requirements in the negative covenants of the Credit Agreement.

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The percentage amount of reduction on the interest rate margin due to repricing the Credit Facilities.

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The amount of debt that was repriced on the effective date.

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Such other amount of the cash flow, as a percentage, described in the Credit Agreement that is required to reduce the aggregate principal amount of New Term Loans outstanding to achieve a target principal amount that declines quarterly based on a pre-determined specified schedule.

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The percentage of the principal amount of the term loans that would be required to be repaid, prepaid, refinanced or replaced if APLP elected to do so within one year of funding date.

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Percentage of the cash flow of APLP Holdings and its subsidiaries that remains after the application of funds, in accordance with a customary priority, to operations and maintenance expenses, debt service on the New Credit Facilities and the MTNs, funding of the debt service reserve account, debt service on other permitted debt of APLP Holdings and its subsidiaries, capital expenditures permitted under the Credit Agreement and payment on the preferred equity issued by Atlantic Power Preferred Equity Ltd. to be applied under mandatory prepayment provisions.

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The percentage of par value of the term loan that APLP may offer to prepay a lender if a Change of Control occurs, as defined in the Credit Agreement.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Amount, after accumulated amortization, of debt discount.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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