Variable Interest Entities (VIEs) (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Variable Interest Entity [Line Items]
Operating Revenues	$ 2,423	$ 2,421	$ 5,183	$ 6,176
Operation and Maintenance	824	744	1,607	1,487
Long Island ServCo [Member]
Variable Interest Entity [Line Items]
Operating Revenues	142	129	292	257
Operation and Maintenance	$ 142	$ 129	$ 292	$ 257

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

- Definition

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 + Details