FAIR VALUE MEASUREMENTS (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Assets:
Price risk management instruments, netting	$ 51	$ 367
Price risk management instruments, assets	527	1,497
TOTAL ASSETS	6,438	7,127
Liabilities:
Price risk management instruments, netting	(23)	(186)
TOTAL LIABILITIES	207	229
Amount primarily related to deferred taxes on appreciation of investment value	627	575
Short-term investments
Assets:
Short-term investments	944	658
Fixed-income securities
Assets:
Short-term investments		49
Nuclear decommissioning trusts
Assets:
Short-term investments	131	117
Global equity securities	1,960	1,845
Fixed-income securities	1,947	1,885
TOTAL ASSETS	4,065	3,872
Customer credit trust
Assets:
Short-term investments	8	19
Global equity securities	185	218
Fixed-income securities	409	508
TOTAL ASSETS	602	745
Rabbi trusts
Assets:
Short-term investments	96	25
Global equity securities	5	5
Fixed-income securities		69
Life insurance contracts	65	64
TOTAL ASSETS	166	163
Long-term disability trust
Assets:
Short-term investments	5	10
TOTAL ASSETS	134	143
Price Risk Derivative, Electricity
Assets:
Price risk management instruments, netting	45	40
Price risk management instruments, assets	516	566
Liabilities:
Price risk management instruments, netting	(21)	(20)
Price risk management instruments, liabilities	203	223
Price Risk Derivative, Gas
Assets:
Price risk management instruments, netting	6	327
Price risk management instruments, assets	11	931
Liabilities:
Price risk management instruments, netting	(2)	(166)
Price risk management instruments, liabilities	4	6
Level 1
Assets:
Price risk management instruments, gross subject to netting	0	0
TOTAL ASSETS	4,654	4,207
Liabilities:
TOTAL LIABILITIES	0	0
Level 1 | Short-term investments
Assets:
Short-term investments	944	658
Level 1 | Fixed-income securities
Assets:
Short-term investments		0
Level 1 | Nuclear decommissioning trusts
Assets:
Short-term investments	131	117
Global equity securities	1,960	1,845
Fixed-income securities	1,191	1,094
TOTAL ASSETS	3,282	3,056
Level 1 | Customer credit trust
Assets:
Short-term investments	8	19
Global equity securities	185	218
Fixed-income securities	129	216
TOTAL ASSETS	322	453
Level 1 | Rabbi trusts
Assets:
Short-term investments	96	25
Global equity securities	5	5
Fixed-income securities		0
Life insurance contracts	0	0
TOTAL ASSETS	101	30
Level 1 | Long-term disability trust
Assets:
Short-term investments	5	10
TOTAL ASSETS	5	10
Level 1 | Price Risk Derivative, Electricity
Assets:
Price risk management instruments, gross subject to netting	0	0
Liabilities:
Price risk management instruments, gross subject to netting	0	0
Level 1 | Price Risk Derivative, Gas
Assets:
Price risk management instruments, gross subject to netting	0	0
Liabilities:
Price risk management instruments, gross subject to netting	0	0
Level 2
Assets:
Price risk management instruments, gross subject to netting	55	698
TOTAL ASSETS	1,156	1,963
Liabilities:
TOTAL LIABILITIES	21	182
Level 2 | Short-term investments
Assets:
Short-term investments	0	0
Level 2 | Fixed-income securities
Assets:
Short-term investments		49
Level 2 | Nuclear decommissioning trusts
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities	756	791
TOTAL ASSETS	756	791
Level 2 | Customer credit trust
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities	280	292
TOTAL ASSETS	280	292
Level 2 | Rabbi trusts
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities		69
Life insurance contracts	65	64
TOTAL ASSETS	65	133
Level 2 | Long-term disability trust
Assets:
Short-term investments	0	0
TOTAL ASSETS	0	0
Level 2 | Price Risk Derivative, Electricity
Assets:
Price risk management instruments, gross subject to netting	50	94
Liabilities:
Price risk management instruments, gross subject to netting	15	10
Level 2 | Price Risk Derivative, Gas
Assets:
Price risk management instruments, gross subject to netting	5	604
Liabilities:
Price risk management instruments, gross subject to netting	6	172
Level 3
Assets:
Price risk management instruments, gross subject to netting	421	432
TOTAL ASSETS	421	432
Liabilities:
TOTAL LIABILITIES	209	233
Level 3 | Short-term investments
Assets:
Short-term investments	0	0
Level 3 | Fixed-income securities
Assets:
Short-term investments		0
Level 3 | Nuclear decommissioning trusts
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities	0	0
TOTAL ASSETS	0	0
Level 3 | Customer credit trust
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities	0	0
TOTAL ASSETS	0	0
Level 3 | Rabbi trusts
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities		0
Life insurance contracts	0	0
TOTAL ASSETS	0	0
Level 3 | Long-term disability trust
Assets:
Short-term investments	0	0
TOTAL ASSETS	0	0
Level 3 | Price Risk Derivative, Electricity
Assets:
Price risk management instruments, gross subject to netting	421	432
Liabilities:
Price risk management instruments, gross subject to netting	209	233
Level 3 | Price Risk Derivative, Gas
Assets:
Price risk management instruments, gross subject to netting	0	0
Liabilities:
Price risk management instruments, gross subject to netting	0	0
Fair Value Measured at Net Asset Value Per Share | Nuclear decommissioning trusts
Assets:
Assets measured at NAV	27	25
Fair Value Measured at Net Asset Value Per Share | Long-term disability trust
Assets:
Assets measured at NAV	$ 129	$ 133