Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Share-Based Compensation [Abstract]

Schedule Of Selected Financial Impact Of Share-Based Compensation

		For the Years Ended December 31,
		2014			2013			2012
Share-based compensation expense included in cost of revenue	$	1,937		$	1,841		$	1,770
Share-based compensation expense included in operating expenses		16,162			14,733			14,152
Total share-based compensation expense included in consolidated statements of income		18,099			16,574			15,922
Income tax benefit resulting from share-based compensation arrangements		(6,107	)		(5,584	)		(5,403	)
Net impact of share-based compensation on net income	$	11,992		$	10,990		$	10,519

Schedule Of Weighted Averages Of The Assumptions Used In Estimating The Fair Value Of Stock Option Awards

	For the Years Ended December 31,
		2014			2013			2012
Expected stock price volatility		28	%		32	%		34	%
Expected term, in years		5.7			4.9			4.6
Risk-free interest rate		1.5	%		1.0	%		0.8	%
Weighted average fair value of options granted	$	36.14		$	27.17		$	26.38

Schedule Of Stock Option Activity

	Number of Options (000)	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value ($000)
Outstanding as of December 31, 2013	2,131	$	63.96
Granted	297		123.24
Exercised	(585)		41.63
Forfeited	(62)		92.53
Expired	(1)		91.68
Outstanding as of December 31, 2014	1,780	$	80.16	4.3	$	121,250
Fully vested as of December 31, 2014	888	$	63.50	2.7	$	75,286
Fully vested and expected to vest as of December 31, 2014	1,710	$	79.13	4.2	$	118,220

Schedule Of Restricted Stock Unit Activity

	Number of Units (000)	Weighted Average Grant-Date Fair Value
Nonvested as of December 31, 2013	336	$	76.67
Granted	98		122.92
Vested	(122)		64.71
Forfeited	(23)		89.25
Nonvested as of December 31, 2014	289	$	96.47
Expected to vest as of December 31, 2014	267	$	95.97