Employee Incentive, Retirement, Deferred Compensation, and Career Achievement Plans (Stock-Based Compensation Expense 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	$ 254	$ 204	$ 183
Income tax benefit on share-based compensation expense	(60)	(49)	(44)
Stock option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	36	36	51
Restricted stock unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	200	156	120
Employee stock purchase plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	18	12	12
Share-based Payment Arrangement, Option Exercised and Restricted Stock units (RSUs) Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit on share-based compensation expense	$ (93)	$ (14)	$ (23)

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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Amount of noncash expense for share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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