SUPPLEMENTAL CASH FLOW INFORMATION (Non-Cash Transactions) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Information [Abstract]
Finance Leases	$ 67
Finance Leases		$ 164	$ 0
Accrued Capital Expenditures	40	31	24
Asset Retirement Obligations Increase (Decrease)	26	20	10
Operating Leases	8
Renewable Energy Credits	3	3	2
Net Cost of Removal Increase (Decrease)	$ (10)	$ (4)	$ (88)

Net cost of removal of interim retirements.

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- Definition

Renewal Energy Credit

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- Definition

Amount of increase in lease obligation from new lease.

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- Definition

Future cash outflow to pay for construction in progress expenditures that have occurred.

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The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations.

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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