ESTIMATES, SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND BALANCE SHEET DETAIL Estimates, Significant Accounting Policies and Balance Sheet Detail - Inventory (Details) MMbtu in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2021 USD ($) MMbtu	Dec. 31, 2020 USD ($) MMbtu
Inventory Accounting Policies [Abstract]
Energy Related Inventory, Natural Gas in Storage	[1]	$ 36	$ 63
Inventory, Raw Materials and Supplies		21	23
Inventories		$ 57	$ 86
Natural Gas Volumes | MMbtu		11.4	29.2
Interest Costs Capitalized		$ 0	$ 2

[1] Natural gas volumes held for operations at December 31, 2021 and 2020 were 11.4 TBtu and 29.2 TBtu, respectively.