Business, Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of Reportable Segments | Segment	3
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholder's Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,941	$ 6,514	$ 8,536	$ 18,115
Proceeds from Sale of Short-Term Investments	1,100	976	3,600
Payments to Acquire Short-Term Investments	$ 1,400	$ 611	$ 2,400
Retained Earnings (Deficit)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholder's Equity, Including Portion Attributable to Noncontrolling Interest				(5,200)
AOCI Attributable to Parent
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholder's Equity, Including Portion Attributable to Noncontrolling Interest				$ (3,900)