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v3.20.2

Derivatives and Risk Management - Additional Information (Details) | 1 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 31, 2020 USD ($) | Jun. 30, 2020 USD ($) MWh MMBTU Contract | Dec. 31, 2019 MWh MMBTU
Canadian [Member] |  |  |
Derivative [Line Items] |  |  |
Number of days Canadian currency prices are settled with U.S. dollars |  | 60 days |
Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Number of interest rate swaps settled | Contract |  | 7 |
Settled derivative notional amount | $ |  | $ 70,000,000.0 |
Interest Rate Swap [Member] | Subsequent Event [Member] |  |  |
Derivative [Line Items] |  |  |
Payments for (proceeds from) derivative instrument operating activities | $ | $ 33,500,000 |  |
Purchase [Member] | Physical [Member] | Electric Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MWh |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MWh |  |  | 0
Purchase [Member] | Physical [Member] | Gas Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MMBTU |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MMBTU |  |  | 0
Purchase [Member] | Financial [Member] | Electric Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MWh |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MWh |  |  | 0
Purchase [Member] | Financial [Member] | Gas Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MMBTU |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MMBTU |  |  | 0
Sales [Member] | Physical [Member] | Electric Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MWh |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MWh |  |  | 0
Sales [Member] | Physical [Member] | Gas Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MMBTU |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MMBTU |  |  | 0
Sales [Member] | Financial [Member] | Electric Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MWh |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MWh |  |  | 0
Sales [Member] | Financial [Member] | Gas Derivative [Member] |  |  |
Derivative [Line Items] |  |  |
Expected deliveries of energy commodity derivatives after 2023 | MMBTU |  | 0 |
Expected deliveries of energy commodity derivatives after 2022 | MMBTU |  |  | 0

X
- Definition Energy commodity derivative expected to be settle after year four. + References No definition available. + Details
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Data Type: | xbrli:integerItemType
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X
- Definition Energy commodity derivative expected to be settle after year three. + References No definition available. + Details
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- Definition Number of interest rate swaps settled. + References No definition available. + Details
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- Definition Number of period currency prices are settled with domestic country currency. + References No definition available. + Details
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- Definition Payments for (proceeds from) derivative instrument operating activities. + References No definition available. + Details
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- Definition Settled derivative notional amount. + References No definition available. + Details
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- 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
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- Details
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- Details
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- Details
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- Details
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