SUPPLEMENTAL CASH FLOW INFORMATION (Non-Cash Transactions) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Supplemental Cash Flow Information [Abstract]
Accrued Capital Expenditures	$ 38	$ 26	$ 40
Asset Retirement Obligations Increase (Decrease)	34	(12)	26
Renewable Energy Credits	3	3	3
Operating Leases	0	1	8
Finance Leases	0	0	67
Net Cost of Removal Increase (Decrease)	$ (41)	$ (34)	$ (10)

Net cost of removal of interim retirements.

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- Definition

Renewal Energy Credit

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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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