OTHER FINANCIAL DATA - CAPITALIZED FINANCING COSTS (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2016 |
Mar. 31, 2015 |
|
| Capitalized Financing Costs Disclosure [Line Items] | ||
| AFUDC related to debt | $ 7 | $ 6 |
| AFUDC related to equity | 27 | 27 |
| Other capitalized financing costs | 18 | 17 |
| Total capitalized financing costs | 52 | 50 |
| San Diego Gas and Electric Company [Member] | ||
| Capitalized Financing Costs Disclosure [Line Items] | ||
| AFUDC related to debt | 4 | 3 |
| AFUDC related to equity | 11 | 8 |
| Total capitalized financing costs | 15 | 11 |
| Southern California Gas Company [Member] | ||
| Capitalized Financing Costs Disclosure [Line Items] | ||
| AFUDC related to debt | 3 | 3 |
| AFUDC related to equity | 10 | 9 |
| Total capitalized financing costs | $ 13 | $ 12 |