Stock-Based Compensation (Additional Information on Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Closing stock price used to calculate intrinsic value	$ 67.90
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices	$22.06 - $27.24
Range of Exercise Prices, Lower Limit	$ 22.06
Range of Exercise Prices, Upper Limit	$ 27.24
Options Outstanding, Number of Options	203,908
Options Outstanding, Weighted Average Remaining Contractual Term (years)	0 years 5 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 25.08
Options Outstanding, Aggregate Intrinsic Value	$ 8,732
Options Exercisable, Exercisable Shares	203,908
Options Exercisable, Weighted Average Remaining Contractual Life (years)	0 years 5 months 1 day
Options Exercisable, Weighted Average Exercise Price	$ 25.08
Options Exercisable, Aggregate Intrinsic Value	8,732
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices	$40.08 - $50.46
Range of Exercise Prices, Lower Limit	$ 40.08
Range of Exercise Prices, Upper Limit	$ 50.46
Options Outstanding, Number of Options	6,506
Options Outstanding, Weighted Average Remaining Contractual Term (years)	1 year 2 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 48.61
Options Outstanding, Aggregate Intrinsic Value	125
Options Exercisable, Exercisable Shares	6,506
Options Exercisable, Weighted Average Remaining Contractual Life (years)	1 year 2 months 1 day
Options Exercisable, Weighted Average Exercise Price	$ 48.61
Options Exercisable, Aggregate Intrinsic Value	125
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices	$57.28 - $59.35
Range of Exercise Prices, Lower Limit	$ 57.28
Range of Exercise Prices, Upper Limit	$ 59.35
Options Outstanding, Number of Options	71,675
Options Outstanding, Weighted Average Remaining Contractual Term (years)	6 years 9 months 4 days
Options Outstanding, Weighted Average Exercise Price	$ 57.46
Options Outstanding, Aggregate Intrinsic Value	749
Options Exercisable, Exercisable Shares	55,205
Options Exercisable, Weighted Average Remaining Contractual Life (years)	6 years 9 months
Options Exercisable, Weighted Average Exercise Price	$ 57.39
Options Exercisable, Aggregate Intrinsic Value	555
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices	$22.06 - $59.35
Range of Exercise Prices, Lower Limit	$ 22.06
Range of Exercise Prices, Upper Limit	$ 59.35
Options Outstanding, Number of Options	282,089
Options Outstanding, Weighted Average Remaining Contractual Term (years)	2 years 0 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 33.85
Options Outstanding, Aggregate Intrinsic Value	9,606
Options Exercisable, Exercisable Shares	265,619
Options Exercisable, Weighted Average Remaining Contractual Life (years)	1 year 9 months
Options Exercisable, Weighted Average Exercise Price	$ 32.37
Options Exercisable, Aggregate Intrinsic Value	9,412
Vested or Expected to Vest [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 22.06
Range of Exercise Prices, Upper Limit	$ 59.35
Vested or Expected to Vest, Range of Exercise Prices	$22.06 - $59.35
Vested or Expected to Vest, Number of Options	282,089
Vested or Expected to Vest, Weighted Average Remaining Contractual Life (years)	2 years 0 months 18 days
Vested or Expected to Vest, Weighted Average Exercise Price	$ 33.85
Vested or Expected to Vest, Aggregate Intrinsic Value	$ 9,606