Variable Interest Entities - Power Purchase Commitment (Details) - Power purchase commitment $ in Millions	1 Months Ended
Nov. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) MW
Variable interest entities
Firm capacity from power purchase agreement (in megawatts) \| MW		236.5
Minimum energy requirements over remaining term of power purchase agreement (in megawatts) \| MW		0
Residual guarantee associated with power purchase agreement		$ 0.0
Required capacity payments		$ 6.4
Whitewater
Variable interest entities
Acquisition purchase price, expected	$ 72.7

Purchase price of expected asset acquisition prior to consideration being transferred.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 50
-Section 15
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6911878&loc=d3e8732-128492

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=123419778&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 810
-SubTopic 10
-Section 50
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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.

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- Definition

Firm capacity, in megawatts, from a power purchase agreement accounted for as a finance lease.

+ References

No definition available.

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- Definition

The minimum energy requirements, in megawatts, over the remaining term of a power purchase agreement accounted for as a finance lease.

+ References

No definition available.

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- Definition

Amount of the residual guarantee associated with a power purchase agreement accounted for as a finance lease.

+ References

No definition available.

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