XML 77 R58.htm IDEA: XBRL DOCUMENT
v3.20.2

Long-term debt - Schedule of Long-term Debt (Detail) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | May 23, 2019
--- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 4,154,776,000 | $ 3,931,868,000 |  |
Less: current portion | (221,827,000) | (225,013,000) |  |
Long-term debt, excluding current portion | $ 3,932,949,000 | 3,706,855,000 |  |
Senior Unsecured Notes | U.S. Dollar Senior Unsecured Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 4.21% |  |  |
Par value | $ 1,125,000,000 |  |  |
Long-term debt | $ 1,120,004,000 | 1,219,579,000 |  |
Senior Unsecured Notes | U.S. Dollar Senior Unsecured Utility Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 6.01% |  |  |
Par value | $ 212,000,000 |  |  |
Long-term debt | $ 227,956,000 | 233,686,000 |  |
Senior Unsecured Notes | U.S Dollar Senior Secured Utility Bonds |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 4.71% |  |  |
Par value | $ 556,000,000 |  |  |
Long-term debt | $ 562,913,000 | 672,337,000 |  |
Senior Unsecured Notes | Canadian Dollar Senior Unsecured Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 4.28% |  |  |
Par value | $ 1,150,669,000 |  |  |
Long-term debt | $ 840,337,000 | 728,679,000 |  |
Senior Unsecured Notes | Canadian Dollar Senior Secured Project Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 10.21% |  |  |
Par value | $ 27,098,000 |  |  |
Long-term debt | 19,870,000 | 21,961,000 |  |
Senior Unsecured Notes | Senior Unsecured Debt |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 3,533,590,000 | 3,310,819,000 |  |
Senior Unsecured Notes | U.S. Dollar Subordinated Unsecured Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average coupon | 6.50% |  |  |
Par value | $ 637,500,000 |  | $ 350,000,000 | $ 350,000,000
Long-term debt | 621,186,000 | 621,049,000 |  |
Revolving Credit Facility | Senior Unsecured Notes | Senior Unsecured Revolving Credit Facilities |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 89,000,000 | 141,577,000 |  |
Revolving Credit Facility | Senior Unsecured Notes | Senior Unsecured Bank Credit Facilities |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 458,510,000 | 75,000,000 |  |
Revolving Credit Facility | Senior Unsecured Notes | Commercial Paper |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 215,000,000 | $ 218,000,000 |  |

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 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_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
Name: | us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
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 unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtCurrent
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 classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_U.SDollarSeniorUnsecuredNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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

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

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