FAIR VALUE MEASUREMENTS (Schedule of Maturities on Debt Securities) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Nuclear decommissioning trusts
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	$ 4,065	$ 3,872
Nuclear decommissioning trusts \| Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	39
1–5 years	635
5–10 years	450
More than 10 years	823
Total maturities of fixed-income securities	1,947	1,885
Customer credit trust
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	602	745
Customer credit trust \| Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	0
1–5 years	128
5–10 years	95
More than 10 years	186
Total maturities of fixed-income securities	$ 409	$ 508

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