Employee Benefit Plans (Accumulated Other Comprehensive Loss Pretax Amounts Not Yet Reflected in Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Accumulated net actuarial losses	$ 857	$ 1,071
Accumulated prior service cost/(credit)	5	4
Total	862	1,075
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated net actuarial losses	170	233
Accumulated prior service cost/(credit)	(21)	(75)
Total	$ 149	$ 158