Share-Based Payments (Exercise Range) (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	128,397
Number Outstanding, Aggregate intrinsic value \| $	$ 6,536
Number Exercisable	68,144
Options Exercisable, Aggregate intrinsic value \| $	$ 4,255
Closing stock price \| $ / shares	$ 230.63
Exercise Price $255.13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	255.13
Exercise Price $208.05 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 208.05
Employee Stock Option [Member] \| Exercise Price $255.13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	20,768
Weighted- Average Remaining Contractual Life	2 years 1 month 6 days
Number Exercisable	20,768
Employee Stock Option [Member] \| Exercise Price $208.05 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	7,000
Weighted- Average Remaining Contractual Life	2 years 2 months 12 days
Number Exercisable	7,000
Stock Appreciation Rights [Member] \| Exercise Price $114.64 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 114.64
Number Outstanding	23,268
Weighted- Average Remaining Contractual Life	2 years 10 months 24 days
Number Exercisable	23,268
Stock Appreciation Rights [Member] \| Exercise Price $132.56 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 132.56
Number Outstanding	28,218
Weighted- Average Remaining Contractual Life	5 years 8 months 12 days
Number Exercisable	13,508
Stock Appreciation Rights [Member] \| Exercise Price $210.22 [Member]]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 210.22
Number Outstanding	34,500
Weighted- Average Remaining Contractual Life	7 years 8 months 12 days
Number Exercisable	3,600
Stock Appreciation Rights [Member] \| Exercise Price $216.48 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 216.48
Number Outstanding	14,643
Weighted- Average Remaining Contractual Life	9 years 10 months 24 days
Number Exercisable	0

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Price of a single share of a number of saleable stocks of a company.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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