XML 80 R63.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Business acquisitions and development projects - Additional Information (Details) $ / shares in Units, CAD in Thousands, $ in Thousands |  |  |  |  |  |  |  |  |  |  |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 18, 2017 USD ($) | Feb. 28, 2017 USD ($) | Feb. 17, 2017 USD ($) | Feb. 15, 2017 MWac | Jan. 01, 2017 USD ($) $ / shares | Dec. 31, 2016 USD ($) | Dec. 30, 2016 USD ($) | Dec. 14, 2016 MWac | Nov. 29, 2016 USD ($) | Jan. 08, 2016 CAD water_utility | Jan. 08, 2016 USD ($) water_utility | Aug. 12, 2015 MWac | Mar. 31, 2018 CAD | Dec. 31, 2016 CAD MWh $ / kWh | Dec. 31, 2018 USD ($) | Dec. 31, 2017 CAD | Dec. 31, 2017 USD ($) | Dec. 31, 2016 CAD | Mar. 31, 2018 $ / shares
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additions to property, plant and equipment | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | CAD 740,023 |  | CAD 405,743 |
Property, plant and equipment | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  | CAD 4,889,946 |  | 7,909,493 |  | 4,889,946 |
Intangible assets | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  | 64,989 |  | CAD 64,108 |  | 64,989 |
Empire |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination, purchase price |  |  |  |  | $ 2,414,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business acquisition, cash paid per common share (usd per share) | $ / shares |  |  |  |  | $ 34.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination, liabilities incurred |  |  |  |  | $ 855,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39 years | 39 years |  |
Park Water Company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination, purchase price |  |  |  |  |  |  |  |  |  | CAD 353,077 | $ 249,540 |  |  |  |  |  |  |  |
Business combination, liabilities incurred |  |  |  |  |  |  |  |  |  |  | $ 91,750 |  |  |  |  |  |  |  |
Number of regulated water utilities | water_utility |  |  |  |  |  |  |  |  |  | 3 | 3 |  |  |  |  |  |  |  |
Revenue | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | CAD 91,817 |  | 96,695 |
Pre-tax net earnings | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | CAD 17,620 |  | CAD 25,374 |
Great Bay Solar Project |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Solar power capacity (megawatt ac) | MWac |  |  |  |  |  |  |  |  |  |  |  | 75 |  |  |  |  |  |  |
Great Bay Solar Facility | Partnership |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership agreement, funded amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 42,750 |  |
Great Bay Solar Facility | Partnership | Tax Investor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership agreement, funded amount | $ 59 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Luning Solar Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Solar power capacity (megawatt ac) | MWac |  |  |  | 50 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Luning Solar Facility | Partnership | Tax Investor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership agreement, funded amount |  |  | $ 31,212 |  |  | $ 7,826 |  |  |  |  |  |  |  |  |  |  |  |  |
Bakersfield Solar Project |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Solar power capacity (megawatt ac) | MWac |  |  |  |  |  |  |  | 20 |  |  |  |  |  |  |  |  |  |  |
Bakersfield Solar Project II |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Solar power capacity (megawatt ac) | MWac |  |  |  |  |  |  |  | 10 |  |  |  |  |  |  |  |  |  |  |
Bakersfield Solar Project II | Tax Investor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership agreement, funded amount |  | $ 9,800 |  |  |  |  |  |  | $ 2,454 |  |  |  |  |  |  |  |  |  |
Wind Turbine Components |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additions to property, plant and equipment | CAD |  |  |  |  |  |  |  |  |  |  |  |  |  | CAD 75,000 |  |  |  |  |
Renewable energy production tax credit (usd per kwh) | $ / kWh |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.023 |  |  |  |  |
Acquisition Facility | Line of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceed from long-term lines of credit |  |  |  |  |  |  | $ 1,336,440 |  |  |  |  |  |  |  |  |  |  |  |
Minimum | Wind Turbine Components |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Wind power capacity (megawatt) | MWh |  |  |  |  |  |  |  |  |  |  |  |  |  | 500 |  |  |  |  |
Maximum | Wind Turbine Components |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Wind power capacity (megawatt) | MWh |  |  |  |  |  |  |  |  |  |  |  |  |  | 700 |  |  |  |  |
Weighted Average | Park Water Company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful lives |  |  |  |  |  |  |  |  |  | 40 years | 40 years |  |  |  |  |  |  |  |
Bridge Loan | Acquisition Facility | Line of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceed from long-term lines of credit |  |  |  |  | $ 1,336,440 |  | $ 1,336,440 |  |  |  |  |  |  |  |  |  |  |  |
Scenario, Forecast [Member] | Perris Water Distribution System |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination, purchase price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 12 |  |  |  |
Scenario, Forecast [Member] | St. Lawrence Gas Company, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination, purchase price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 70 |  |  |  |
Atlantica Yield | Scenario, Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity interest |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00%
Total purchase price | CAD |  |  |  |  |  |  |  |  |  |  |  |  | CAD 608 |  |  |  |  |  |
Equity Method Investment, Share Price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 24.25
Business Acquisition, Share Price, Contingent Payment | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.60

X
- Definition Business Combination, Number of Regulated Water Utilities + References No definition available. + Details
Name: | aqunf_BusinessCombinationNumberofRegulatedWaterUtilities
Namespace Prefix: | aqunf_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity Method Investment, Share Price + References No definition available. + Details
Name: | aqunf_EquityMethodInvestmentSharePrice
Namespace Prefix: | aqunf_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Equity Method Investment, Share Price, Contingent Payment + References No definition available. + Details
Name: | aqunf_EquityMethodInvestmentSharePriceContingentPayment
Namespace Prefix: | aqunf_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Partnership Agreement, Funded Amount + References No definition available. + Details
Name: | aqunf_PartnershipAgreementFundedAmount
Namespace Prefix: | aqunf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Renewable Energy Production Tax Credit + References No definition available. + Details
Name: | aqunf_PublicUtilitiesRenewableEnergyProductionTaxCredit
Namespace Prefix: | aqunf_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | duration

X
- Definition Solar Power Capacity + References No definition available. + Details
Name: | aqunf_SolarPowerCapacity
Namespace Prefix: | aqunf_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Wind Power Capacity + References No definition available. + Details
Name: | aqunf_WindPowerCapacity
Namespace Prefix: | aqunf_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
Name: | us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination. + References No definition available. + Details
Name: | us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph ((a)(1),(b)) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
Name: | us-gaap_IntangibleAssetsNetExcludingGoodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquireEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromLongTermLinesOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(14)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=aqunf_TheEmpireDistrictElectricCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=aqunf_ParkWaterCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aqunf_GreatBaySolarProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aqunf_GreatBaySolarFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis=us-gaap_PartnershipMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CounterpartyNameAxis=aqunf_TaxInvestorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aqunf_LuningSolarFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aqunf_BakersfieldSolarProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aqunf_BakersfieldSolarProjectIIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=aqunf_WindTurbineComponentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=aqunf_PerrisWaterDistributionSystemMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=aqunf_St.LawrenceGasCompanyInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=aqunf_AtlanticaYieldMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |