Related Party Transactions - Schedule of Related Party Balances (Details) - Related Party - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Owed By	$ 11	$ 5
Owed To	0	(39)
Iberdrola, S.A.
Related Party Transaction [Line Items]
Owed By	1	1
Owed To	0	(29)
Iberdrola Renovables Energia, S.L.
Related Party Transaction [Line Items]
Owed By	4	0
Owed To	0	0
Iberdrola Financiación, S.A.U.
Related Party Transaction [Line Items]
Owed By	0	0
Owed To	(799)	(9)
Vineyard Wind 1
Related Party Transaction [Line Items]
Owed By	6	3
Owed To	(8)	(8)
Iberdrola Solutions
Related Party Transaction [Line Items]
Owed By	0	0
Owed To	(6)	(2)
Other
Related Party Transaction [Line Items]
Owed By	4	4
Owed To	$ 0	$ (1)

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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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.

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