Acquisitions - (Schedule of Merger Related Costs) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Transition Services	$ 18	$ 0
Professional fees (bank, legal, consulting)	1	47
Representation & warranty insurance	0	11
Contract buyouts, terminations and transfers	3	8
Due diligence and environmental	2	4
Employee-related	1	3
Other	2	3
Merger-related expenses	27	76	$ 41
Indigo Merger
Business Acquisition [Line Items]
Transition Services	0	0
Professional fees (bank, legal, consulting)	0	27
Representation & warranty insurance	0	4
Contract buyouts, terminations and transfers	1	7
Due diligence and environmental	1	3
Employee-related	0	2
Other	0	2
Merger-related expenses	2	45
GEPH Merger
Business Acquisition [Line Items]
Transition Services	18	0
Professional fees (bank, legal, consulting)	1	19
Representation & warranty insurance	0	7
Contract buyouts, terminations and transfers	2	1
Due diligence and environmental	1	1
Employee-related	1	0
Other	2	0
Merger-related expenses	$ 25	28
Montage Merger
Business Acquisition [Line Items]
Transition Services		0	0
Professional fees (bank, legal, consulting)		1	18
Representation & warranty insurance		0	0
Contract buyouts, terminations and transfers		0	5
Due diligence and environmental		0	0
Employee-related		1	17
Other		1	1
Merger-related expenses		$ 3	$ 41

Business Combination, Acquisition Related Costs, Other

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Due Diligence And Environmental Expense

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Representation And Warranty Insurance

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Transition Services

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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