Condensed Financial Information (Parent Company) (Long-term Debt - Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Condensed Financial Statements, Captions [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 108	$ 87
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	1,800
Long-term Debt, Maturities, Repayments of Principal in Year Two	1,300
Long-term Debt, Maturities, Repayments of Principal in Year Three	180
Long-term Debt, Maturities, Repayments of Principal in Year Four	52
Long-term Debt, Maturities, Repayments of Principal in Year Five	348
Long-term Debt, Maturities, Repayments of Principal after Year Five	11,900
Parent Company
Condensed Financial Statements, Captions [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	1,400
Long-term Debt, Maturities, Repayments of Principal in Year Two	1,200
Long-term Debt, Maturities, Repayments of Principal in Year Three	476
Long-term Debt, Maturities, Repayments of Principal in Year Four	0
Long-term Debt, Maturities, Repayments of Principal in Year Five	237
Long-term Debt, Maturities, Repayments of Principal after Year Five	12,700
Senior Notes	14,516	13,588
Parent Company | Senior Notes Unaffiliated [Member]
Condensed Financial Statements, Captions [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	106	83
Senior Notes	14,516	13,588
Parent Company | Senior Notes, Affiliated [Member]
Condensed Financial Statements, Captions [Line Items]
Senior Notes	$ 1,585	$ 1,676