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Share-Based Compensation Summary of the Corporation's Restricted Stock Unit Activity and Related Information (Details) - Restricted Stock Units (RSUs) shares in Thousands	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Service-Based Units
Restricted shares outstanding at January 1, 2021 | shares	1,048
Non-vested shares granted | shares	456
Restricted shares forfeited | shares	(41)
Restricted shares vested | shares	(117)
Restricted shares outstanding at December 31, 2021 | shares	1,346
Restricted shares outstanding at January 1, 2021 (Weighted-average grant-date fair value) | $ / shares	$ 61.52
Non-vested shares granted (Weighted-average grant-date fair value) | $ / shares	60.92
Restricted shares forfeited (Weighted-average grant-date fair value) | $ / shares	62.09
Restricted shares vested (Weighted-average grant-date fair value) | $ / shares	86.13
Restricted shares outstanding at December 31, 2021 (Weighted-average grant-date fair value) | $ / shares	$ 59.18
Performance-Based Units
Restricted shares outstanding at January 1, 2021 | shares	690
Non-vested shares granted | shares	332
Restricted shares forfeited | shares	(17)
Restricted shares vested | shares	(189)
Restricted shares outstanding at December 31, 2021 | shares	816
Restricted shares outstanding at January 1, 2021 (Weighted-average grant-date fair value) | $ / shares	$ 73.48
Non-vested shares granted (Weighted-average grant-date fair value) | $ / shares	58.64
Restricted shares forfeited (Weighted-average grant-date fair value) | $ / shares	64.38
Restricted shares vested (Weighted-average grant-date fair value) | $ / shares	93.02
Restricted shares outstanding at December 31, 2021 (Weighted-average grant-date fair value) | $ / shares	$ 63.12

X

- Definition

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

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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.

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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).

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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.

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