Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of transactions with related party during the financial reporting period.

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Related Party Transactions - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Deposit balance	$ 0		$ 150,000,000
Iberdrola Solutions
Related Party Transaction [Line Items]
Notes payable	4,000,000		0
Affiliated Entity
Related Party Transaction [Line Items]
Impairments	0
Iberdrola Financiacion, S.A.U
Related Party Transaction [Line Items]
Line of credit facility, maximum borrowing capacity	$ 500,000,000
Credit facility, commitment fee percentage	0.105%
Credit facility outstanding amount	$ 0		$ 0
Iberdrola, S.A. \| Siemens-Gamesa
Related Party Transaction [Line Items]
Business acquisition, percentage of voting interests acquired	8.10%
Related party transaction, amount	$ 11,000,000	$ 18,000,000