ACQUISTIONS, DIVESTITURES AND DISCONTINUED OPERATIONS - Schedule of Purchase Price Allocation (Details) - Oncor Electric Delivery Holdings Company LLC [Member] $ in Millions	Mar. 09, 2018 USD ($)
Assets acquired:
Accounts receivable	$ 1
Due from unconsolidated affiliates	46
Investment in Oncor Holdings	9,227
Deferred income taxes	287
Other noncurrent assets	109
Total assets acquired	9,670
Liabilities assumed:
Other current liabilities	23
Pension and other postretirement benefit plan obligations	21
Deferred credits and other	58
Total liabilities assumed	102
Net assets acquired	9,568
Total purchase price paid	$ 9,568