Employee Benefit Plans - Schedule of amounts for pension and retirement expenses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Retirement Benefits [Abstract]
Service cost	$ 0	$ 4	$ 1	$ 11
Non-service pension benefit	0	(20)	(5)	(45)
Total	$ 0	$ (16)	$ (4)	$ (34)