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Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Stock Based Compensation [Abstract]

Schedule of Share based Payment Award Restricted Stock Valuation Assumptions

The following is a summary of the key assumptions used in the valuation calculations for market based awards granted during the years ended December 31, 2020, 2019 and 2018:

		2020			2019			2018
Risk free rate		1.603%			2.578%			1.61% - 2.14%
Dividend yield		3.070%			4.043%			3.884%
Volatility		17.02%			18.95%			15.05% - 17.18%
Requisite service period		3 years			3 years			3 years

Nonvested Restricted Stock Shares Activity

A summary of the status of the nonvested restricted shares as of December 31, 2020, and the changes for the year ended December 31, 2020, is presented below:

Nonvested Shares		Shares				Weighted Average Grant-Date Fair Value
Nonvested as of January 1, 2020			233,878			$	96.33
Issued			152,729				88.56
Vested			(169,198	)			81.69
Forfeited			(559	)			106.86
Nonvested as of December 31, 2020			216,850			$	102.10

Share-based Compensation, Stock Options, Activity

A summary of the status of the outstanding stock options as of December 31, 2020 and the changes for the year ended December 31, 2020 is presented below:

Stock Options		Options				Weighted Average Exercise Price
Outstanding as of January 1, 2020			20,763			$	77.82
Exercised			(918	)			77.77
Outstanding as of December 31, 2020			19,845			$	77.83

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Schedule of Share-based Payment Award, Restricted Stock, Valuation Assumptions [Table Text Block]

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Stock Based Compensation [Abstract]

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Tabular disclosure of the changes in outstanding nonvested restricted stock shares.

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-Publisher FASB
-Name Accounting Standards Codification
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Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.

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