FAIR VALUE MEASUREMENTS (Schedule of Maturities on Debt Securities) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Nuclear decommissioning trusts
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	$ 3,850	$ 4,581
Nuclear decommissioning trusts \| Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	11
1–5 years	620
5–10 years	461
More than 10 years	847
Total maturities of fixed-income securities	1,939	$ 2,024
Customer credit trust
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	478
Customer credit trust \| Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	0
1–5 years	38
5–10 years	116
More than 10 years	94
Total maturities of fixed-income securities	$ 248

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