Realignment Charges (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Charges
Accrued Realignment Costs
Realignment Costs incurred	$ 71	$ 49	$ 126	$ 51
Executive Transition Costs | Realignment Program [Member]
Accrued Realignment Costs
Realignment Costs incurred	0	20	0	22
Employee Severance [Member]
Accrued Realignment Costs
Realignment Costs incurred			65	27
Balance - December 31, 2019			47
Payments made			75
Balance - March 31, 2019	37	27	37	27
Employee Severance [Member] | Realignment Program [Member]
Accrued Realignment Costs
Realignment Costs incurred	0	27	0	27
Employee Severance [Member] | 2020 Fit for Growth [Member]
Accrued Realignment Costs
Realignment Costs incurred	39	0	65	0
Employee Retention Costs [Member] | Realignment Program [Member]
Accrued Realignment Costs
Realignment Costs incurred	9	0	15	0
Employee Retention Costs [Member] | 2020 Fit for Growth [Member]
Accrued Realignment Costs
Realignment Costs incurred	1	0	5	0
Other Restructuring | Realignment Program [Member]
Accrued Realignment Costs
Realignment Costs incurred	3	2	17	2
Exit From Content Related Services [Member] | 2020 Fit for Growth [Member]
Accrued Realignment Costs
Realignment Costs incurred	8		19
Facility Closing | 2020 Fit for Growth [Member]
Accrued Realignment Costs
Realignment Costs incurred	19	$ 0	24	$ 0
Restructuring and Related Cost, Accelerated Depreciation	$ 1		$ 4