Employee Benefit Plans (Schedule of Allocation of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	$ 48,945	$ 47,960
Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	9,663	8,688
Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	16,761	15,003
Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,467	1,650	$ 1,885
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	21,088	21,810
Global Equities [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	6,160	6,199
Global Equities [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	6,156	6,194
Global Equities [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	4	5
Global Equities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Global Equities [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Global Equity Commingled Funds [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,012	588
Global Equity Commingled Funds [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	20
Global Equity Commingled Funds [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,012	568
Global Equity Commingled Funds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Global Equity Commingled Funds [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Enhanced Global Equities [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	22
Enhanced Global Equities [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	(53)
Enhanced Global Equities [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	75
Enhanced Global Equities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Enhanced Global Equities [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Public Equities
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	2,308	5,771
Other Public Equities | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Public Equities | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Public Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Public Equities | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	2,308	5,771
Private Equity Funds [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	4,936	4,068
Private Equity Funds [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Private Equity Funds [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Private Equity Funds [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Private Equity Funds [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	4,936	4,068
Governments [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	5,067	3,952
Governments [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	3,507	2,526
Governments [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,560	1,426
Governments [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Governments [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Corporate Debt Securities [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	13,185	12,639
Corporate Debt Securities [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	1
Corporate Debt Securities [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	13,185	12,638
Corporate Debt Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Corporate Debt Securities [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Structured Products
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	57	57
Structured Products | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Structured Products | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	57	57
Structured Products | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Structured Products | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Fixed Income Securities [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	9,669	6,975
Fixed Income Securities [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Fixed Income Securities [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Fixed Income Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Fixed Income Securities [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	9,669	6,975
Real Estate [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	3,099	3,411
Real Estate [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Real Estate [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Real Estate [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,467	1,650
Real Estate [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	1,632	1,761
Other Pension Plan Assets [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	2,975	3,155
Other Pension Plan Assets [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Pension Plan Assets [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	560	84
Other Pension Plan Assets [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Other Pension Plan Assets [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	2,415	3,071
Cash & Cash Equivalents [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	511	314
Cash & Cash Equivalents [Member] | Quoted price in active markets (Level 1) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Cash & Cash Equivalents [Member] | Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	383	150
Cash & Cash Equivalents [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	0	0
Cash & Cash Equivalents [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	128	164
Pension Plan Assets Leveled [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan asset, subtotal	48,979	47,151
Other Assets And Liabilities [Member]
Defined Benefit Plan, Plan Assets, Allocation [Line Items]
Fair value of plan assets	$ (34)	$ 809