Employee Benefit Plans - Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pension Benefits Cost
Components of expense/ (income) related to net benefit expense:
Service Cost Included in Labor and Fringe	$ 8	$ 10	$ 24	$ 28
Interest Cost	16	13	48	40
Expected Return on Plan Assets	(47)	(46)	(141)	(139)
Amortization of Net Loss	12	18	37	55
Total Included in Other Income - Net	(19)	(15)	(56)	(44)
Net Periodic Benefit Credit	(11)	(5)	(32)	(16)
Other Post-retirement Benefits Cost
Components of expense/ (income) related to net benefit expense:
Service Cost Included in Labor and Fringe	0	1	0	1
Interest Cost	0	0	1	1
Amortization of Prior Service Credits	(2)	(2)	(5)	(6)
Total Included in Other Income - Net	(2)	(2)	(4)	(5)
Net Periodic Benefit Credit	$ (2)	$ (1)	$ (4)	$ (4)