Share-Based Compensation (Stock Option Awards) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	248,000	433,750
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	3 years 8 months 12 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 49.85	$ 49.11
Options Exercisable, Number of Options	188,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 51.86
$33.61-47.61 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	105,500
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	6 years 6 months
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 43.67
Options Exercisable, Number of Options	45,500
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 43.86
Range of Exercise Prices, lower limit (in dollars per share)	$ 33.61
Range of Exercise Prices, upper limit (in dollars per share)	$ 47.61
$50.01-52.13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	63,500
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	2 years 2 months 12 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 51.03
Options Exercisable, Number of Options	63,500
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 51.03
Range of Exercise Prices, lower limit (in dollars per share)	$ 50.01
Range of Exercise Prices, upper limit (in dollars per share)	$ 52.13
$54.93-58.83 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	79,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	1 year 3 months 18 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 57.14
Options Exercisable, Number of Options	79,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 57.14
Range of Exercise Prices, lower limit (in dollars per share)	$ 54.93
Range of Exercise Prices, upper limit (in dollars per share)	$ 58.83