Share-Based Payments (Exercise Range) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 210.22
Number Outstanding	130,004
Number Outstanding, Aggregate intrinsic value	$ 7,646
Options Exercisable	46,372
Options Exercisable, Aggregate intrinsic value	$ 3,273
Closing stock price	$ 244.50
Exercise Price $150.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 150.00
Number Outstanding	2,000
Weighted-Average Remaining Contractual Life	2 months 12 days
Options Exercisable	2,000
Exercise Price $255.13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 255.13
Number Outstanding	22,418
Weighted-Average Remaining Contractual Life	4 years
Options Exercisable	13,511
Exercise Price $208.05 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 208.05
Number Outstanding	9,000
Weighted-Average Remaining Contractual Life	4 years 2 months 12 days
Options Exercisable	9,000
Exercise Price $236 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 236.00
Number Outstanding	250
Weighted-Average Remaining Contractual Life	4 years 4 months 24 days
Options Exercisable	150
Exercise Price $114.64 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 114.64
Number Outstanding	27,068
Weighted-Average Remaining Contractual Life	4 years 10 months 24 days
Options Exercisable	18,111
Exercise Price $132.56 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price		$ 132.56
Number Outstanding	32,268
Weighted-Average Remaining Contractual Life	7 years 9 months 18 days
Options Exercisable	3,600
Exercise Price $ 210.22 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	37,000
Weighted-Average Remaining Contractual Life	9 years 8 months 12 days
Options Exercisable	0