v3.20.2

Leases - PPA Leases (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
May 31, 2019 USD ($) | Sep. 30, 2020 USD ($) project agreement | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) project agreement | Sep. 30, 2019 USD ($)
Lessor, Lease, Description [Line Items] |  |  |  |  |
Lease, Practical Expedients, Package [true false] |  |  |  | true |
Number of PPAs accounted for as operating leases | agreement |  | 10 |  | 10 |
Number of project which are in operation | project |  | 21 |  | 21 |
Lessor, Operating Lease, Existence of Option to Extend [true false] |  |  |  | false |
Operating Lease, Lease Income [Abstract] |  |  |  |  |
Rental income from operating leases |  | $ 35.2 | $ 42.3 | $ 115.6 | $ 133.4
Minimum |  |  |  |  |
Lessor, Lease, Description [Line Items] |  |  |  |  |
Remaining lease term |  |  |  | 19 months |
Maximum |  |  |  |  |
Lessor, Lease, Description [Line Items] |  |  |  |  |
Remaining lease term |  |  |  | 23 years |
Manchief |  |  |  |  |
Operating Lease Lessor Sale Of Plant [Abstract] |  |  |  |  |
Sales price of Manchief plant | $ 45.2 |  |  |  |
Mamquam | BC Hydro |  |  |  |  |
Operating Lease Lessor Sale Of Plant [Abstract] |  |  |  |  |
Period of time between the anniversaries the option to purchase will become exercisable after the option is first exercisable |  |  |  | 5 years |
Solid Fuel |  |  |  |  |
Operating Lease, Lease Income [Abstract] |  |  |  |  |
Rental income from operating leases |  | 19.0 | 26.1 | $ 51.1 | 64.4
Natural Gas |  |  |  |  |
Operating Lease, Lease Income [Abstract] |  |  |  |  |
Rental income from operating leases |  | 7.0 | 6.5 | 19.0 | 18.4
Hydroelectric |  |  |  |  |
Operating Lease, Lease Income [Abstract] |  |  |  |  |
Rental income from operating leases |  | $ 9.2 | $ 9.7 | $ 45.5 | $ 50.6

X
- Definition Period between anniversaries from the date the option to purchase is first exercisable. + References No definition available. + Details
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- Definition Sales price of plant under PPA accounted for as a lease per agreement. + References No definition available. + Details
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- Definition Remaining lease term of lessor operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The number of PPAs accounted for as operating leases under lessor. + References No definition available. + Details
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- Definition Indicates (true false) whether practical expedients are elected for not reassessing whether any expired or existing contract is or contains lease, lease classification for expired or existing lease, and initial direct cost for any existing lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL77916155-209984 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL77916155-209984 + 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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- Definition Indicates (true false) whether lessor has option to extend operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919359-209981 + Details
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- Definition Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 + Details
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