Employee Pension and Other Postretirement Benefits Schedule of Allocation Plan Asset (Table) (Details) - USD ($) $ in Millions		Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 8,460	$ 7,710
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,528	2,261
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,033	2,402
Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4,561	4,663
Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,899	3,047
U.S. and international equities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,481	2,224
U.S. and international equities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,481	2,224
U.S. and international equities | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	1,994	1,881
Government and agency debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		477	466
Government and agency debt securities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		477	466
Corporate and other debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,553	1,933
Corporate and other debt securities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,553	1,933
Corporate and other debt securities | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		327	240
Group annuity contract | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	3
Group annuity contract | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	3
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		47	37
Cash and cash equivalents | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		47	37
Cash and cash equivalents | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[2]	232	78
Real Estate Investments | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		467	317
Partnership [Member] | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		518	202
Hedge funds | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 361	$ 329
Minimum | United States and International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		35.00%
Minimum | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		20.00%
Minimum | Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		10.00%
Maximum | United States and International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		60.00%
Maximum | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		45.00%
Maximum | Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		35.00%

[1] U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds.

[2] Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle.