Business Segments (Corporate Items) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Expenses:
Total revenues	$ 1,535	$ 1,651
Amortization expense of acquired intangible assets	40	36
Merger and strategic initiatives expense	15	45
Restructuring charges	0	10
Operating income	405	365
Corporate Items
Expenses:
Total revenues	1	15
Amortization expense of acquired intangible assets	40	36
Merger and strategic initiatives expense	15	45
Restructuring charges	0	10
Expenses - divested/contributed businesses	0	5
Other	4	2
Total expenses	59	98
Operating income	$ (58)	$ (83)