Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

Summary of Assumptions for Options Issued

The assumptions used to determine the grant date fair value for options issued during 2019, 2018, and 2017 are presented below:

	2019		2018		2017
Expected term (in years)	5.5		5.3		5.3
Volatility	23.6	%	23.0	%	24.9	%
Weighted-average risk-free interest rate	2.50	%	2.69	%	1.95	%
Dividend yield	1.02	%	0.74	%	0.60	%

Summary of Options Including Non-Plan Stock Options

A summary of the status of our options as of December 31, 2019, and changes during the year, is presented below:

	2019
	Shares	Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (In Thousands)
Stock Options:
Outstanding at beginning of year	790,744	$	22.48	2.18	$	13,235
Plus: Granted	120,019	43.28
Less: Exercised	(475,090)	16.74
Forfeited	(4,937)	46.87
Outstanding at end of year	430,736	34.33		3.16	4,550
Nonvested at end of year	140,076	43.91		5.61	166
Exercisable at end of year	290,660	29.70		1.98	4,099

Schedule of Nonvested Stock Option Outstanding

The following table provides information about our nonvested stock options outstanding at December 31, 2019:

	2019
	Shares	Weighted- Average Exercise Price		Weighted- Average Grant Date Fair Value
Stock Options:
Nonvested at beginning of period	124,348	$	42.76	$	10.38
Plus: Granted	120,019	43.28		10.26
Less: Vested	(104,291)	41.80		10.04
Forfeited	—	—		—
Nonvested at end of period	140,076	43.91		10.53

Schedule of RSAs and RSUs

The following table summarizes the Company’s RSUs and changes during the year:

	Units (in whole)	Weighted Average Grant-Date Fair Value per Unit
Balance at December 31, 2018	95,707	$	43.08
Plus: Granted	72,151	43.28
Less: Vested	(38,737)	40.38
Forfeited	(6,461)	44.20
Balance at December 31, 2019	122,660	44.24