Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2020

Stock-Based Compensation [Abstract]

Schedule of Assumptions Used to Estimate Fair Value of Stock Options

	For the six months ended
	June 30,
	2020	2019
Risk free interest rate	1.66%	1.84% - 2.47%
Dividend yield	1.3%	1.3%
Expected volatility	20%	20%
Expected lives	4.6 years	4.6 years

Summary of Stock Option Activity

		Weighted-		Weighted-Average
		Average		Remaining
	Number	Exercise Price		Contractual	Aggregate
	of Shares	Per Share		Life (in years)	Intrinsic Value
Outstanding at December 31, 2019	4,507	$	133.68
Granted	10	$	240.99
Exercised	(1,164)	$	109.72
Forfeited/canceled	(19)	$	171.25
Outstanding at June 30, 2020	3,334	$	142.15	4.2	$	519,323
Exercisable at June 30, 2020	1,821	$	124.40	3.5	$	316,048
Unvested at June 30, 2020	1,513	$	163.53	5.1	$	203,275

Summary of Restricted Stock Unit and Performance Based Restricted Stock Unit Activity

	RSUs			PSUs
		Weighted-Average			Weighted-Average
	Number of	Grant Date Fair		Number of	Grant Date Fair
	Shares	Value per Share		Shares	Value per Share
	(in thousands)			(in thousands)
Outstanding at December 31, 2019	313	$	152.98	—	$	—
Granted (1)	98	$	290.67	149	$	375.81
Vested	(129)	$	141.90	—	$	—
Forfeited/canceled	(5)	$	190.95	—	$	—
Outstanding at June 30, 2020	277	$	206.26	149	$	375.81

(1)PSUs represent the target number of shares granted that are issuable at the end of the three year performance period. Fair value for a portion of the PSUs was calculated using a Monte Carlo simulation model.