Retirement and Employee Benefit Plans Narrative (Details) - USD ($) $ in Millions	11 Months Ended	12 Months Ended
	Dec. 13, 2019	Dec. 31, 2020	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic benefit cost	$ 5		$ 8	$ 38
Projected benefit obligation			173		$ 198
Accumulated benefit obligation for defined benefit pension plans					2
Employer contributions	5		5
Level 2 [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets			123		$ 144
Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contribution expenses related to the defined contribution plans which cover certain employees	$ 31		$ 37	$ 24
Forecast [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated future employer contributions in next fiscal year, cash		$ 5