Segment Information (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) segment	Jun. 30, 2022 USD ($) segment
Segment Reporting Information [Line Items]
Number of reportable segments | segment			2	2
Revenues	$ 4,656,000,000	$ 5,093,000,000	$ 9,772,000,000	$ 9,765,000,000
Intersegment, Nonoperating
Segment Reporting Information [Line Items]
Revenues			$ 0	$ 0