Stock Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

The following tables summarize option activity for the three-month period ended March 31, 2021:

						Weighted		Aggregate
				Weighted		Average		Intrinsic
				Average		Remaining		Value
	Options			Exercise Price		Contractual Life		(in 000’s)
Outstanding options at January 1, 2021		1,632,334		$	70.67
Options granted		44,496			97.64
Options exercised		(121,645	)		56.04
Options canceled/forfeited		(600	)		93.24
Outstanding options at March 31, 2021		1,554,585		$	72.57		5.17	$	60,622
Exercisable options at March 31, 2021		563,215		$	61.80		3.75	$	28,029

Summary of Weighted Average Grant-date Assumptions and Weighted Average Fair Values

The fair value of options was estimated using a Black-Scholes based option pricing model with the following weighted average grant-date assumptions and weighted average fair values as of March 31:

	2021			2020
Weighted-average fair value of grants	$	13.82		$	14.48
Risk-free interest rates		0.27	%		1.54	%
Dividend yield		2.30	%		2.69	%
Expected volatility		22.67	%		22.68	%
Expected option life		4.96	years		4.99	years

Schedule of Restricted Stock Units Activity

				Weighted
				Average
				Grant Date
	RSUs			Fair Value
Nonvested at January 1, 2021		47,658		$	81.53
Reinvested		102			112.16
Forfeited		(51	)		93.42
Nonvested at March 31, 2021		47,709		$	81.58