EMPLOYEE BENEFIT PLANS - PROFIT SHARING PLANS (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Chilquinta Energia Profit Sharing [Member] | |||
| Profit Sharing Plans [Line Items] | |||
| Recorded Annual Profit Sharing Expense | $ 5 | $ 3 | $ 4 |
| Luz del Sur Profit Sharing [Member] | |||
| Profit Sharing Plans [Line Items] | |||
| Recorded Annual Profit Sharing Expense | $ 10 | $ 10 | $ 10 |