Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Fair Value Assumptions for Stock Options

The following are the weighted-average assumptions used to calculate the grant-date fair values of stock option awards granted in the years ended December 31, 2019, 2018 and 2017:

	For the Years Ended December 31
	2019	2018	2017
Expected dividend yield	1.32%	1.34%	1.39%
Expected volatility	26.98%	27.41%	30.01%
Expected term	7.3 years	7.3 years	7.2 years
Risk-free interest rate	2.53%	2.88%	2.22%

Summary of Stock Option Activity

A summary of stock option activity for the year ended December 31, 2019 is presented below:

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value ($000)
Options
Outstanding at January 1, 2019		361,543		$	58.83
Granted		74,262			92.09
Exercised		(59,799	)		50.78
Forfeited		(15,184	)		79.12
Outstanding at December 31, 2019		360,822			66.15		6.62	$	13,093
Vested or expected to vest at December 31, 2019		350,805			65.69		6.58		12,891
Exercisable at December 31, 2019		270,871			60.09		6.00		11,470

Summary of Stock Award Activity

A summary of stock award activity for the year ended December 31, 2019, is presented below:

	Shares			Weighted-Average Grant Date Fair Value
Stock Awards
Unvested at January 1, 2019		85,370		$	73.65
Granted		45,327			89.12
Vested		(28,595	)		77.90
Forfeited		(14,768	)		70.76
Unvested at December 31, 2019		87,334			80.78

Summary of SARs Activity

The following is a summary of SARs activity for the year ended December 31, 2019:

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value ($000)
SARs
Outstanding at January 1, 2019		639,146		$	60.64
Granted		166,518			92.02
Exercised		(104,367	)		51.13
Forfeited		(45,880	)		79.12
Outstanding at December 31, 2019		655,417			68.83		6.89	$	22,048