Stock Plans and Share-Based Compensation - Share-Based Compensation and Related Income Tax Benefit (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 107	$ 29	$ 74
Income Tax Benefit	23	19	43
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	71	(3)	42
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	18	19	18
Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	12	6	8
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	4	5	4
Stock Awards for Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 2	$ 2	$ 2