Disclosure of the aggregate tax benefit realized from the issuance of stock and settlement of RPSRs and RSRs.

No definition available.

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Ultimate vesting percentages based on continued performance targets.

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Number of shares transferred by employees to the company during the period to satisfy minimum tax obligations resulting from share-based compensation arrangements.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Net number of non-option equity instruments granted to participants.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Stock Compensation Plans (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock awards
Stock rights, weighted-average grant date fair value	$ 191.23		$ 191.23
Stock awards, vested in the period			0.1	0.1
Maximum
Stock awards
Stock awards, transferred for employee withholding taxes			0.1	0.1
Restricted performance stock rights
Stock awards
Stock rights, granted			0.2	0.1
Stock rights, weighted-average grant date fair value	$ 180.05	$ 230.10	$ 180.05	$ 230.10
Restricted performance stock rights \| Minimum
Stock awards
Restricted performance stock rights ultimate vesting percentage	0.00%		0.00%
Restricted performance stock rights \| Maximum
Stock awards
Restricted performance stock rights ultimate vesting percentage	200.00%		200.00%
Stock Awards [Member]
Stock awards
Employee Service Share-Based Compensation, Tax Benefit Realized From Issuance Of Instruments Other Than Options			$ 2.0	$ 3.0
Stock Awards [Member] \| Maximum
Stock awards
Employee Service Share-Based Compensation, Tax Benefit Realized From Issuance Of Instruments Other Than Options	$ 1.0	$ 1.0