Other Postretirement Benefits - Additional Information (Details) - Other Postretirement Benefits - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in liability for other postretirement benefits	$ (50,000,000)	$ 62,000,000
Noncurrent liabilities	72,000,000	79,000,000
Increase (decrease) in regulatory liabilities	2,000,000
Other comprehensive income (loss), unrecognized net losses	2,000,000
Other comprehensive (income) loss, prior service cost	0
Expected contributions	1,000,000
CECONY
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in liability for other postretirement benefits	(21,000,000)	35,000,000
Noncurrent liabilities	27,000,000	$ 55,000,000
Increase (decrease) in regulatory liabilities	11,000,000
Other comprehensive income (loss), unrecognized net losses	1,000,000
Other comprehensive (income) loss, prior service cost	$ 0