Share-Based Compensation (Stock Option Awards) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	168,000	248,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	3 years 9 months 21 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 48.14	$ 49.85
Options Exercisable, Number of Options	128,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 49.58
$33.61-47.61 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	88,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	6 years 1 month 21 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 43.29
Options Exercisable, Number of Options	48,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 43.09
Range of Exercise Prices, lower limit (in dollars per share)	33.61
Range of Exercise Prices, upper limit (in dollars per share)	$ 47.61
$50.01-51.51 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	38,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	2 years
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 50.72
Options Exercisable, Number of Options	38,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 50.72
Range of Exercise Prices, lower limit (in dollars per share)	50.01
Range of Exercise Prices, upper limit (in dollars per share)	$ 51.51
$54.93-57.50 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options	42,000
Options Outstanding, Weighted-Avg. Remaining Contractual Life (Years)	9 months 21 days
Options Outstanding, Weighted-Avg. Exercise Price (in dollars per share)	$ 55.96
Options Exercisable, Number of Options	42,000
Options Exercisable, Weighted-Avg. Exercise Price (in dollars per share)	$ 55.96
Range of Exercise Prices, lower limit (in dollars per share)	54.93
Range of Exercise Prices, upper limit (in dollars per share)	$ 57.50