Employee Benefit Plans - Net Periodic Benefit Expense (Income) (Details) - Pension Plans - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of Net Periodic Benefit Expense (Income)
Service cost, benefits earned during the period	$ 19	$ 17	$ 16
Interest cost on projected benefit obligation	104	121	139
Expected return on plan assets	(48)	(77)	(114)
Net amortization of prior service cost	1	1	1
Net amortization of actuarial loss	34	26	13
Net periodic benefit expense	$ 110	$ 88	$ 55