Share-Based Compensation Plans (Performance Share Activity) (Details) - Performance Based Shares shares in Thousands	12 Months Ended
Dec. 31, 2020 $ / shares shares
Summary of Performance-based shares activity
Vested \| shares	(89)
Weighted Average Grant Date Fair Value / Share
Weighted Average Grant Date Fair Value, Vested \| $ / shares	$ 49.15
ROIC Performance Share Unit Grants
Summary of Performance-based shares activity
Outstanding Shares, Beginning \| shares	225
Granted \| shares	82
Forfeited \| shares	(36)
Outstanding Shares, Ending \| shares	182
Weighted Average Grant Date Fair Value / Share
Weighted Average Grant Date Fair Value, Outstanding at January 1, 2016 \| $ / shares	$ 64.51
Weighted Average Grant Date Fair Value, Granted \| $ / shares	78.90
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	76.67
Weighted Average Grant Date Fair Value, Outstanding at December 31, 2016 \| $ / shares	$ 76.12
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Adjustments In Period \| shares	0
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Adjustments In Period, Weighted Average Grant Date Fair Value \| $ / shares	$ 0
TSR Performance Share Unit Grants
Summary of Performance-based shares activity
Outstanding Shares, Beginning \| shares	225
Granted \| shares	82
Vested \| shares	(124)
Forfeited \| shares	(36)
Outstanding Shares, Ending \| shares	182
Weighted Average Grant Date Fair Value / Share
Weighted Average Grant Date Fair Value, Outstanding at January 1, 2016 \| $ / shares	$ 75.80
Weighted Average Grant Date Fair Value, Granted \| $ / shares	102.05
Weighted Average Grant Date Fair Value, Vested \| $ / shares	47.81
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	92.03
Weighted Average Grant Date Fair Value, Outstanding at December 31, 2016 \| $ / shares	$ 96.98
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Adjustments In Period \| shares	35
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Adjustments In Period, Weighted Average Grant Date Fair Value \| $ / shares	$ 47.81

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

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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Name Accounting Standards Codification
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

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.

+ References

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-Publisher FASB
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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Adjustments In Period

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