v3.20.1

Leases - PPA Leases (Details) $ in Millions | 1 Months Ended | 3 Months Ended
--- | --- | ---
May 31, 2019 USD ($) | Mar. 31, 2020 USD ($) agreement project | Mar. 31, 2019 USD ($)
Lessor, Lease, Description [Line Items] |  |  |
Lease, Practical Expedients, Package [true false] |  | true |
Number of PPAs accounted for as operating leases | agreement |  | 11 |
Number of PPAs accounted for as direct financing leases | project |  | 1 |
Number of project which are in operation | project |  | 21 |
Lessor, Operating Lease, Existence of Option to Extend [true false] |  | false |
Assets and Liabilities, Lessor [Abstract] |  |  |
Net investment in direct financing lease |  | $ 0.4 |
Operating Lease, Lease Income [Abstract] |  |  |
Rental income from operating leases |  | $ 40.8 | $ 44.4
Minimum |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Lessor, Operating Lease, Term of Contract |  | 2 months |
Maximum |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Lessor, Operating Lease, Term of Contract |  | 24 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 |  | $ 16.6 | 19.7
Natural Gas |  |  |
Operating Lease, Lease Income [Abstract] |  |  |
Rental income from operating leases |  | 5.9 | 6.3
Hydroelectric |  |  |
Operating Lease, Lease Income [Abstract] |  |  |
Rental income from operating leases |  | $ 18.3 | $ 18.4

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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 The number of PPAs accounted for as direct financing leases under lessor. + References No definition available. + Details
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- Definition Represents the number of power generation projects which are in operation. + References No definition available. + Details
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- Definition Amount of net investment in direct financing lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919379-209981 + 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=119364159&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=119364159&loc=SL77916155-209984 + 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=119202524&loc=SL77919359-209981 + Details
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- Definition Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=119202524&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=118952077&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=119202524&loc=SL77919372-209981 + Details
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