Other Material Contingencies - Con Edison Transmission (Details) - Payment Guarantee by CET Electric of Contributions to New York Transco LLC	6 Months Ended
Jun. 30, 2020
Guarantor Obligations [Line Items]
Estimated project cost percentage	175.00%
NY Transco
Guarantor Obligations [Line Items]
Ownership interest, percentage	45.70%

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.

No definition available.

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