DERIVATIVE FINANCIAL INSTRUMENTS - CONTINGENT FEATURES (Details) - USD ($) $ in Millions |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Aggregate fair value of net liability position | $ 10 | $ 6 |
| Aggregate fair value of additional collateral | 13 | |
| San Diego Gas and Electric Company [Member] | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Aggregate fair value of net liability position | 0 | $ 5 |
| Aggregate fair value of additional collateral | $ 3 |