Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2016

Stock-Based Compensation [Abstract]

Schedule Of Assumptions Used To Estimate Fair Value Of Stock Options

	For the nine months ended
	September 30,
	2016	2015
Risk free interest rate	1.11% - 1.43%	1.21% - 1.45%
Dividend yield	0.0%	0.0%
Expected volatility	20.0%	20.0%
Expected lives	4.7 years	4.6 years

Company's Activities With Respect To Its Stock Options

				Weighted-
		Weighted-		Average
		Average		Remaining
	Number	Exercise Price		Contractual	Aggregate
	of Shares	Per Share		Life (in years)	Intrinsic Value
Outstanding at December 31, 2015	3,794	$	84.66
Granted	1,357	$	96.64
Exercised	(572)	$	44.74
Canceled	(98)	$	105.11
Outstanding at September 30, 2016	4,481	$	92.94	4.8	$	98,486
Exercisable at September 30, 2016	1,666	$	77.43	3.5	$	60,961
Unvested at September 30, 2016	2,815	$	102.11	5.6	$	37,525

Company's Restricted Stock Unit Activity

		Weighted-
		Average
		Grant Date
	Number of	Fair Value per
	Units	Share
	(in thousands)
Outstanding at December 31, 2015	277	$	97.14
Granted	137	$	96.76
Vested	(114)	$	84.43
Forfeited/canceled	(9)	$	103.24
Outstanding at September 30, 2016	291	$	101.74