Retirement and Employee Benefit Plans (Pension and Other Postretirement Benefit Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 7	$ 7
Interest cost	4	5	5
Expected return on plan assets	(4)	(6)	(6)
Amortization of transition obligation	0	0	0
Amortization of prior service cost	0	0	0
Amortization of net loss	0	1	2
Net periodic benefit cost	0	7	8
Curtailment gain	0	0	0
Settlement loss	2	0	6
Total benefit cost	2	7	14
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	1
Interest cost	0	0	0
Expected return on plan assets	0	0	0
Amortization of transition obligation	0	0	0
Amortization of prior service cost	0	0	0
Amortization of net loss	0	0	0
Net periodic benefit cost	2	2	1
Curtailment gain	0	0	0
Settlement loss	0	0	0
Total benefit cost	$ 2	$ 2	$ 1