XML 79 R124.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Financial instruments - Additional Information (Detail) |  | 3 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 25, 2018 USD ($) | Jun. 30, 2019 | Dec. 31, 2019 USD ($) $ / MWh MWh | Dec. 31, 2018 USD ($) | Dec. 31, 2019 CAD ($) $ / MWh | May 23, 2019 USD ($) | Mar. 31, 2019 | Jan. 29, 2019 CAD ($) | Oct. 17, 2018 USD ($) | Jan. 31, 2017 USD ($) | Jan. 31, 2014 USD ($) | Dec. 31, 2012 USD ($)
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MWh |  |  | 151,680 |  |  |  |  |  |  |  |  |
Cost per Megawatt Hour | $ / MWh |  |  | 38.95 |  |  |  |  |  |  |  |  |
Long-term debt |  |  | $ 3,931,868,000 | $ 3,336,795,000 |  |  |  |  |  |  |  |
Realized gain/(loss) in OCI from foreign exchange forward contract |  |  | $ 7,795,000 | (27,969,000) |  |  |  |  |  |  |  |
Revenue collection period |  |  | 45 days |  |  |  |  |  |  |  |  |
Cash on hand |  |  | $ 62,485,000 |  |  |  |  |  |  |  |  |
Available for drawn on senior debt facilities |  |  | 1,047,216,000 |  |  |  |  |  |  |  |  |
Utility Services |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Accounts receivable balances |  |  | 200,594,000 |  |  |  |  |  |  |  |  |
Liberty Power Group |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Realized gain/(loss) in OCI from foreign exchange forward contract |  |  | (15,946,000) | 41,244,000 |  |  |  |  |  |  |  |
Bonds |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  | $ 135,000,000 |  |  |  |  |  |  |
Bonds | Plan |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term | 10 years |  |  |  |  |  |  |  |  |  |  |
Long-term debt | $ 135,000,000 |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes | Senior Unsecured Notes Due January 2029 |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term |  | 10 years |  |  |  |  |  |  |  |  |  |
Interest Rate |  |  |  |  |  |  | 4.60% |  |  |  |  |
Par value |  |  |  |  |  |  |  | $ 300,000,000 |  |  |  |
Senior Unsecured Notes | U.S. Dollar Subordinated Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  | 621,049,000 | 278,771,000 |  |  |  |  |  |  |  |
Interest Rate |  |  |  |  |  | 6.20% |  |  |  |  |  |
Par value |  |  | 637,500,000 |  |  | $ 350,000,000 |  |  | $ 287,500 |  |  |
Senior Unsecured Notes | Liberty Power Group | 4.82% Senior Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Par value |  |  |  |  |  |  |  |  |  |  |  | $ 150,000,000
Senior Unsecured Notes | Liberty Power Group | 4.65% Senior Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Par value |  |  |  |  |  |  |  |  |  |  | $ 200,000,000 |
Senior Unsecured Notes | Liberty Power Group | Convertible Unsecured Subordinated Debentures |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Par value |  |  |  |  |  |  |  |  |  | $ 300,000,000 |  |
Forward contracts |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Realized gain/(loss) in OCI from foreign exchange forward contract |  |  | 983,000 | (1,115,000) |  |  |  |  |  |  |  |
Foreign exchange contract |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Realized gain/(loss) in OCI from foreign exchange forward contract |  |  | $ 35,277,000 | $ (28,705,000) |  |  |  |  |  |  |  |
Cash flow hedge | Interest rate swaps |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Term of forward-starting interest rate swap |  |  | 10 years |  |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forward price | $ / MWh |  |  | 13.33 |  | 13.33 |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forward price | $ / MWh |  |  | 178.65 |  | 178.65 |  |  |  |  |  |  |
Weighted Average |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forward price | $ / MWh |  |  | 23.66 |  | 23.66 |  |  |  |  |  |  |
Non-regulated Energy Sales |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unrealized gains in AOCI to be reclassified |  |  | $ 8,704,000 |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unrealized gains in AOCI to be reclassified |  |  | $ 2,203,000 |  |  |  |  |  |  |  |  |
Accounts Receivable | Credit Concentration Risk | Liberty Power Group |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of revenue contributed |  |  | 87.00% |  |  |  |  |  |  |  |  |
Atlantica Yield Energy Solutions Canada, Inc |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Equity method investment, prepayment |  |  | $ 53,750,000 |  |  |  |  |  |  |  |  |
Atlantica Yield Energy Solutions Canada, Inc | Measurement Input, Price Volatility | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Alternative Investment, Measurement Input |  |  | 0.18 |  | 0.18 |  |  |  |  |  |  |
Atlantica Yield Energy Solutions Canada, Inc | Measurement Input, Price Volatility | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Alternative Investment, Measurement Input |  |  | 0.22 |  | 0.22 |  |  |  |  |  |  |
AYES Canada | Measurement Input, Discount Rate | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Alternative Investment, Measurement Input |  |  | 0.0875 |  | 0.0875 |  |  |  |  |  |  |
AYES Canada | Measurement Input, Discount Rate | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Alternative Investment, Measurement Input |  |  | 0.0950 |  | 0.0950 |  |  |  |  |  |  |
AYES Canada | Measurement Input, Discount Rate | Weighted Average |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Alternative Investment, Measurement Input |  |  | 0.0942 |  | 0.0942 |  |  |  |  |  |  |
Sugar Creek |  |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent |  |  | $ 15,765 |  |  |  |  |  |  |  |  |

X
- Definition Cost per Megawatt Hour + References No definition available. + Details
Name: | aqunf_CostperMegawattHour
Namespace Prefix: | aqunf_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity Method Investment, Prepayment + References No definition available. + Details
Name: | aqunf_EquityMethodInvestmentPrepayment
Namespace Prefix: | aqunf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Revenue Target Period + References No definition available. + Details
Name: | aqunf_RevenueTargetPeriod
Namespace Prefix: | aqunf_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(5)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
Name: | us-gaap_AccountsReceivableNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure alternative investment. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_AlternativeInvestmentMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631418-115840 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631419-115840 + Details
Name: | us-gaap_Cash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
Name: | us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The forward price on the price risk forward or futures contract, such as a gas futures contract. + References No definition available. + Details
Name: | us-gaap_DerivativeForwardPrice
Namespace Prefix: | us-gaap_
Data Type: | srt-types:perUnitItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountEnergyMeasure
Namespace Prefix: | us-gaap_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DerivativeTermOfContract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (b,c) -URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount before tax of reclassification adjustments of other comprehensive income (loss) attributable to parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580 + Details
Name: | us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=aqunf_UtilityServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=aqunf_GenerationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_BondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=us-gaap_ScenarioPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aqunf_SeniorUnsecuredNotesDueJanuary2029Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aqunf_U.S.DollarSubordinatedUnsecuredNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aqunf_SeniorUnsecuredNotes4.82Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aqunf_SeniorUnsecuredNotes4.65Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aqunf_ConvertibleUnsecuredSubordinatedDebenturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForwardContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=aqunf_NonregulatedEnergySalesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_InterestExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=aqunf_AtlanticaYieldEnergySolutionsCanadaInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputPriceVolatilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=aqunf_AYESCanadaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=aqunf_SugarCreekMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |