Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity for the year ended December 31, 2021 for employees:

	Options			Weighted Average Exercise price		Weighted Average Remaining Contractual Life (years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020		148,920		$	79.20		5.2		15,130
Granted		19,250
Exercised		(46,741	)
Forfeited		(470	)
Outstanding at December 31, 2021		120,959		$	98.28		4.7	$	28,879
Exercisable at December 31, 2021		9,556		$	92.92		4.6	$	2,333

Summary of Weighted Average Assumptions Used In Valuing Options

The following table summarizes the weighted average assumptions used in valuing options for the years ended December 31, 2021, 2020 and 2019:

	2021			2020			2019
Risk-free interest rate		1.19	%		1.66	%		2.70	%
Expected life in years		3.5			3.2			3.1
Expected volatility		40.57	%		32.80	%		35.57	%
Dividend rate		—			—			—

Summary of Unvested Option

The following table summarizes the status of the Company’s unvested options as of December 31, 2021 and changes during the year ended December 31, 2021:

	Options			Weighted Average Grant-date Fair  Value
Unvested at December 31, 2020		148,920		$	22.07
Granted		19,250			62.65
Vested		(56,297	)		24.22
Forfeited		(470	)		62.65
Unvested at December 31, 2021		111,403		$	27.83

Summary of Restricted Stock Activity

The following table summarizes restricted stock activity during the year ended December 31, 2021:

	Shares			Weighted Average Grant-date Fair  Value
Restricted Stock at December 31, 2020		74,156		$	73.84
Granted		13,653			215.42
Vested		(25,553	)		55.36
Forfeited		(185	)		200.81
Restricted Stock at December 31, 2021		62,071		$	112.21