Stock Based Compensation Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Weighted-average grant date fair value of incentive/performance unit awards and restricted share/restricted share unit awards granted	$ 154.91	$ 198.28	$ 161.04
Total intrinsic value of incentive/performance unit and restricted share/restricted share unit awards vested during the year.	$ 219	$ 322	$ 207

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(02)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Balance Type:	na
Period Type:	duration