FAIR VALUE MEASUREMENTS (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Assets:
Price risk management instruments, netting	$ 10	$ 367
Price risk management instruments, assets	369	1,497
TOTAL ASSETS	5,501	7,127
Liabilities:
Price risk management instruments, netting	(7)	(186)
TOTAL LIABILITIES	228	229
Amount primarily related to deferred taxes on appreciation of investment value	631	575
Short-term investments
Assets:
Short-term investments	487	658
Fixed-income securities
Assets:
Short-term investments		49
Nuclear decommissioning trusts
Assets:
Short-term investments	125	117
Global equity securities	1,933	1,845
Fixed-income securities	1,967	1,885
TOTAL ASSETS	4,041	3,872
Customer credit trust
Assets:
Short-term investments	108	19
Global equity securities	92	218
Fixed-income securities	119	508
TOTAL ASSETS	319	745
Rabbi trusts
Assets:
Short-term investments	98	25
Global equity securities	5	5
Fixed-income securities		69
Life insurance contracts	66	64
TOTAL ASSETS	169	163
Long-term disability trust
Assets:
Short-term investments	6	10
TOTAL ASSETS	116	143
Price Risk Derivative, Electricity
Assets:
Price risk management instruments, netting	1	40
Price risk management instruments, assets	340	566
Liabilities:
Price risk management instruments, netting	(6)	(20)
Price risk management instruments, liabilities	211	223
Price Risk Derivative, Gas
Assets:
Price risk management instruments, netting	9	327
Price risk management instruments, assets	29	931
Liabilities:
Price risk management instruments, netting	(1)	(166)
Price risk management instruments, liabilities	17	6
Level 1
Assets:
Price risk management instruments, gross subject to netting	0	0
TOTAL ASSETS	3,988	4,207
Liabilities:
TOTAL LIABILITIES	0	0
Level 1 | Short-term investments
Assets:
Short-term investments	487	658
Level 1 | Fixed-income securities
Assets:
Short-term investments		0
Level 1 | Nuclear decommissioning trusts
Assets:
Short-term investments	125	117
Global equity securities	1,933	1,845
Fixed-income securities	1,112	1,094
TOTAL ASSETS	3,170	3,056
Level 1 | Customer credit trust
Assets:
Short-term investments	108	19
Global equity securities	92	218
Fixed-income securities	22	216
TOTAL ASSETS	222	453
Level 1 | Rabbi trusts
Assets:
Short-term investments	98	25
Global equity securities	5	5
Fixed-income securities		0
Life insurance contracts	0	0
TOTAL ASSETS	103	30
Level 1 | Long-term disability trust
Assets:
Short-term investments	6	10
TOTAL ASSETS	6	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	33	698
TOTAL ASSETS	1,051	1,963
Liabilities:
TOTAL LIABILITIES	47	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	855	791
TOTAL ASSETS	855	791
Level 2 | Customer credit trust
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities	97	292
TOTAL ASSETS	97	292
Level 2 | Rabbi trusts
Assets:
Short-term investments	0	0
Global equity securities	0	0
Fixed-income securities		69
Life insurance contracts	66	64
TOTAL ASSETS	66	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	13	94
Liabilities:
Price risk management instruments, gross subject to netting	29	10
Level 2 | Price Risk Derivative, Gas
Assets:
Price risk management instruments, gross subject to netting	20	604
Liabilities:
Price risk management instruments, gross subject to netting	18	172
Level 3
Assets:
Price risk management instruments, gross subject to netting	326	432
TOTAL ASSETS	326	432
Liabilities:
TOTAL LIABILITIES	188	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	326	432
Liabilities:
Price risk management instruments, gross subject to netting	188	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	16	25
Fair Value Measured at Net Asset Value Per Share | Long-term disability trust
Assets:
Assets measured at NAV	$ 110	$ 133