Leases - Cottonwood Sale Leaseback Agreement (Details)	Sep. 30, 2020 USD ($)
Cottonwood Energy
Lessor, Lease, Description [Line Items]
Fixed lease payments per year	$ 40,000,000.0

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.

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