XML 122 R106.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Income taxes - Income (Loss) Before Taxes (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items] |  |
Income/(loss) before taxes | $ 132,461 | $ 175,132
Canada |  |
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items] |  |
Income/(loss) before taxes | (109,537) | (2,711)
U.S. |  |
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items] |  |
Income/(loss) before taxes | $ 241,998 | $ 177,843

X
- Definition Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items] + References No definition available. + Details
Name: | aqunf_ScheduleOfComponentsOfIncomeBeforeIncomeTaxExpenseBenefitLineItems
Namespace Prefix: | aqunf_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_StatementGeographicalAxis=country_CA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |