XML 142 R125.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Financial instruments - Long-term Energy Derivative Contracts (Detail) - Cash flow hedge | Dec. 31, 2017 MWh $ / MWh
--- | ---
PJM Western HUB |
Derivative [Line Items] |
Notional quantity (MW-hrs) | MWh | 688,147
Receive average prices (per MW-hr) | $ / MWh | 40.40
NI HUB |
Derivative [Line Items] |
Notional quantity (MW-hrs) | MWh | 2,926,922
Receive average prices (per MW-hr) | $ / MWh | 29.26
ERCOT North HUB |
Derivative [Line Items] |
Notional quantity (MW-hrs) | MWh | 3,330,876
Receive average prices (per MW-hr) | $ / MWh | 36.46

X
- Definition Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNonmonetaryNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition The average strike price on the group of price risk option contracts such as put options or call options. + References No definition available. + Details
Name: | us-gaap_DerivativeAveragePriceRiskOptionStrikePrice
Namespace Prefix: | us-gaap_
Data Type: | us-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
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermContractForPurchaseOfElectricPowerAxis=aqunf_PJMWesternHUBExpiryDecember2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermContractForPurchaseOfElectricPowerAxis=aqunf_NIHUBExpiryDecember2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermContractForPurchaseOfElectricPowerAxis=aqunf_ERCOTNorthHUBExpiryDecember2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |